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. THE COVER

View ofthe Libby bridge from th e w est bank ofthe Imjin R iver soon

after the bridge’s com pletion in J une 1953.



-

B R I ’D G IN G TH E IMJ IN

CONSTRUCTION OF LIBBY AND

TEAL BRIDGES

DURING THE KOREAN WAR

(OCTOBERl952-JULY 1953)

William R . F a r q u h a r , J r.

and

Henry A. Jeffers, Jr.edited and with an introduction by

Charles Hendricks

Studies in Militar y En gineer ingNumber 5

OFFICE OF HISTORY UNITED STATES ARMY CORPS OF ENGINEERS

FORT BELVOIR, VIRGINIA

1989



Lib ra r y o f C o n g res s C a t a lo gin g i n F ’u b l i c a t i o n D a t a

Farquhar, William R.Bridging the Imjin.

(Studies in military engineering; no. )

Includes index.1. Korean War, 1950-1953-Eng inee r i ng and construction.

2. Imjin River (Korea)-Bridges. I. Jeffers, Henry A.

II. Hendricks, Charles, 1946- 111. Title.

IV. Series.DS920.4 .F37 1989 951.9’042 88-600476

Second Printing 1992

EP 870- 1-32

For sale by the Superintendent of Documents, U.S. Government I?c=inting mceWashington, D.C. 20402



Foreword

As th e 40th a nn iversa ry of th e Korea n War appr oaches, we in

the Corps of Engineers should reexamine how our predecessors

overcame the engineering challenges posed by the rugged and

unforgiving environment in which that war was fought. A

nu mber of memoirs an d stu dies h ave evalua ted Korean War com-

bat in some deta il, but th us far litt le ha s been pu blished about th e

U.S. Army engineers ’ war t ime effort s t o conquer the Korean

ter ra in with highways, bridges, port s, and pipelines. Bridging the

Imjin represents a beginning in the effort to fill that gap.

During the last two years of the Korean War, the flood-prone

Imjin River, whose wat ers could qu ickly rise 40 feet , flowed just a

few miles behind a long st ret ch of a llied bat t le lines. Arm y engi-

neers thus faced a critical requirement to construct secure

bridges across t ha t wat er ba rr ier. This book exam ines the effort sof one engineer unit, the 84th Engineer Construction Battalion,

and it s super ior comm and echelons t o overcome t he ser ious chal-

lenges posed by the u npr edicta ble wat ers of th e Imjin. The bat ta l-

ion’s st ory is spiced with int erest ing exam ples of crea t ive -engi-

neer responses to deficiencies of equipment, building materials,

an d tr ained man power, circum sta nces th at ar e so typical of war -

time field construction. The 84th Engineer Battalion more r e -

’ cently served seven years in Vietnam and now is stationed inHawaii.

An impor ta n t con tr ibut ion of th is volume is the publicat ion for

the firs t t ime of a 1953 report on t he cons t ru ct ion u nder difficu lt

field conditions of two durable bridges across the Imjin. This

historical report an d t he a tt ached docum ents an d photos a ssem-

bled by its authors lay largely unnoticed in federal repositories

. . .111



- -1 -

un til uneart hed by our sta ff historians. Combined with a n int ro-duction th at places th e report in context, this h istory provides aninstructive example of imaginative engineering in the face of ,

cha llenging wart ime requirement s. ,

ALBERT J . GENE TTI, J R.Colonel, Corps of EngineersChief of Sta ff

iv



-

Editor’s Preface

Korea’s monsoon r a ins and t he floodwat ers th ey spawnedposed some of the most difficult technical challenges faced by theUnited Stat es Army engineer units serving in the Korean War .Nowhere were th ose cha llenges more pressing tha n a long th elower Imjin River, where tides, ice, and summer floods repeatedly

. threatened to break critical supply lines to United Nations forces

which for t wo years mann ed defensive lines just ten kilometersnorthwest of the river. After struggling for more t han a year withmixed success to span th e lower Im jin with bridges that couldsurvive the st ream’s fury, Amer ican military engineers fina llyconquered th is river in the last year of the war with two modernbridges erected a t s ites where ear lier spans h ad failed.

A report prepared in Korea by the milita ry history staff of the8086th Army Unit tells the story of the construction of these two

successful span s, known as the Teal and Libby br idges. MajorsWilliam R. Fa rquh ar , J r., and Henry A. Jeffers, J r., dra fted thena rr at ive report in 1953 and a tt ached to it copies of a number of relat ed documents . The U.S. Army Center of Milita ry Historyholds a typescript copy of that report. Farquhar and Jeffers pro-vide an inst ru ct ive accoun t of the accomplishm ent of a difficultwar t ime engineer ing assignment, one which r equired consider-able imaginat ion, determina tion, and persevera nce. Innovat ivetechniques developed by officers and en listed men of the ba ttalionserved to overcome t he difficulties imposed both by the physicalproblems involved and by the short ages of equipment and tra inedma npower. As m y intr oduction to th eir repor t explains, U.S.Army engineers foun d th at it was no easy task to overcome thewartime challenges of the, Imjin River.

In editing Farquhar ’s and J effers’ valuable nar ra tive, I ha veat tempted to modernize or corr ect t he spelling and grammar, and,in several inst ances, I ha ve corrected minor missta tements of fact

in order to avoid discrepancies between the report and contempor-ary documents. I have also amended the footnotes of the originalstudy. I selected for publicat ion 46 photographs drawn from the 57

V



included with the origina l report an d 31 oth ers taken from thecollections of the National Archives, the Defense Still MediaRecords Center, the Office of History of the Corps of Engineers,and the Combined Field Army @OK/US). The book contains fourmaps, which I prepared using informat ion cont ained on cont em-

pora ry maps foun d in u nit h istory records in t he Na tiona l Ar -chives.

I selected for th is publica tion th e documen ts cont a ined inthree of the eleven appendixes a tt ached to the original report andadded a fourth appendix drawn from a contemporary document.Appendix A, taken from Tab 3 of the original study, contains theofficial cor respondence in which I Corps a sked for the replace-ment of the failed high-level Teal and X-Ray bridges, and Eighth

Army approved ima ginat ive plans for n ew crossings there. Ap-pendix B cont ains t he en gineer ing report of Eight h Army’s 2dEn gineer Const ru ction Group th at illust ra tes th e mann er inwhich the Teal site was evaluated prior to the decision to build alow-level bridge there. This appendix was at Tab 1 of the originalstudy. Appendix C repr oduces the sect ion ent itled “Genera l De-script ion” of the four-page mimeographed documen t “Libby H i-Level Highway Bridge,” which was prepar ed by the 84th En gi-

neer Const ruction Bat talion in 1953 and signed by Major WilliamC. Car ter , J r ., the bat talion’s opera t ions officer . A copy of thedocument is cont ained in the Papers of William Clar ence Car ter ,J r., at t he m ce of Hist ory, Hea dqua rt ers , U.S. Army Corps of Engineers. The last an d longest of the a ppendixes is th e “Log of Libby Bridge,” writt en by Majors Car ter and Sam E . Fa irchild,his predecessor as operations officer of the 84th Engineer Battal-ion.

.

I have made every effort to preserve or, when required, torestore t he integrity of the documents pr inted in t he appendixes.The first three of these appendixes consist of documents tha t werecopied manually from the originals by Major Jeffers. I have cor-rected copying errors found in t he document s in Appendix B bycomparing Jeffers’ manual copies with carbon copies of the samedocum ent s dra wn from Box 1 of th e Pa pers of Fr an k Ot to Bowma nat the Hoover Inst itu t ion Archives, Stan ford, Californ ia. I havenot found any other copies of the document s in Appendix A, and

th us th ey appear substa nt ially as copied in th e 1953 report . Isimply rea rr an ged th e sect ions of th is appendix to put th em in

Vl



chronological order an d corrected err ors of spelling, gra mmar,an d punctu at ion. I have not altered th e ha stily writt en “Log of Libby Bridge” except to correct spelling and punctuation, to addletters oblitera ted at th e edges of the t yped version of the logcopied at Tab 7 of th e origina l s tu dy, an d t o ad d explan at ory n otes.

In doing th is and in making the few factua l changes required inthe origina l narr at ive, I was great ly assisted by the late ColonelWilliam C. Cart er, J r., who was the primary author of th e log andth e project superintendent of the const ruction of Libby bridge. Iowe a special debt of gra t itude for his help.

Sincere t hanks ar e also due to the editors who have assistedmy work on th is publication-Chris Ha rdyman, J oyce Hardy -man, an d Dian e Arms. Archivist s Morris Izlar and FYed Pernell of

the Nationa l Archives and Elena Danielson of the Hoover Inst itu-tion on War , Revolut ion an d Peace provided valuable assistan cewith documentar y resear ch and photo and map collect ion. Armycar togra pher Arthu r S. Hardyman advised me on militar y mapmaking. Robert R. Weekes prepared the cover.

CHARLES HENDRICKS

vii



Contents

I N T R O D U C T I O N by CharZes Hendricks . . . . . . . . . . . . . . . . 3

CONSTRUCTION OF LIBBY AND TEAL BRIDGES,

IMJIN RIVER,

OCTOBER 1952 TO JULY 1953

by William R. Farquhar, Jr., and Henry A. J efers, J r.

PREFACE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27Chapter

I. BACKGROUND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

II. THE CONSTRUCTION OF TEAL BRIDGE . . . . . . . 35

III. CONSTRUCTION OF X-RAY (LIBBY)

BRIDGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

Appendix

A. CORRESPONDENCE BETWEEN I CORPS ANDEIGHTH ARMY LEADING TO THE APPRQVAL

OF THE CONSTRUCTION OF TEAL BRIDGE.. 71

B. ENGINEERING REPORT ON BRIDGE STUDY

AND DESIGN, TEAL SITE, IMJIN RIVER, 2D

ENGINEER CONSTRUCTION GROUP, 14 SEP-

TEMBER 1952, WITH-SELECTED ATTACHED

DOCUMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .80

C. EXCERPT FROM LIBBY HI-LEVEL HIGHWAY

BRIDGE, A PAPER SIGNED ABOUT JULY 1953

BY MAJOR WILLIAM C. CARTER, JR., OPERA-

TIONS OF FICER, 84TH ENGINEER BATTAL-

ION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98

D. LOG OF LIBBY BRIDGE, COMPILED BY MAJ OR

WILLIAM C. CARTER, J R., OPE RATIONS OF FI-

CER, 84TH ENGINEER CONSTRUCTION BAT-

TALION (22 NOVEMBER 1952-5 JULY 1953)

AND MAJOR SAM E. FAIRCHILD, HIS

PREDECESSOR IN THAT POSITION . . . . . . . . . 99

ix





Fig.

12. The High-level Teal Bridge Collapsing Under t hePr essure of Floodwat er on 30 July 1952

13 . Pier Fr om t he Collapsed High-level Teal BridgeLodged Against Pr otective Fender Piles a t the

Reopened Spa n of the freedom Gate Bridgeon 30 J uly 1952

14. The High-level Teal Bridge in Ea rly August 1952Showing Dama ge Done by Floodwat er on 30 J uly

15. The High-level Teal Bridge After the Flood of 24-25August 1952

16. A Survivor: The High-level Whitefront Timber-pileBridge in September 1952

17. Spoon bill Br idge18. Sout h Korean Art illery Convoy Crossing Libby

Bridge on 23 May 1983

19. X-Ray Sit e in October 1952 Showing Newly Er ectedPonton Bridge an d P erpendicular Volcan ic Rock Banks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Figures 20-37, relating to the construction of Teal bridge,appear between pages 36 and 46:

20. Engineers Driving 16.inch Armco Steel-Column Pilesfor the Low-level Teal Bridge in October 1952

21. Cables Used To Align Piles Tha t Ha d “Walked” WhenDriven Agains t Large Boulders in t he Riverbed

22. A Near ly Completed P ier Fea tu r ing Diagona lChann el-iron Bracing

23. Troops Const ru ct ing Blackout Shelters for NightWelding That Could Double as Curing Cabins inCold Weather

24. Troops F illing the Hollow Armco Piles With Concret e25. Anchor Bolts Set in a Concret e-filled Pile Capped by

12-inch H-beams26. Teal Site on 26 November 1952 Showing Completed

Piers at Sout h End of Bridge and Others Still

Under Shelters27. Thirt y-six-inch I-beams in P lace on Br idge With a P ileDriver Working on One of the Northernmost Piers

28. Side View of Girders in Place

xi



Fig.

29. Troops Pla cing Decking Fr om P ier 16 to the Nort hAbutment

30. Girders in P lace on Piers 8 Through 11

31. Teal Bridge From the South Sh ore on 7 J anu ary 1953as Troops P lace Decking on th e North En d32. Teal Bridge from th e Nort h Shore on 16 J anua ry

1953 When Almost Completed33. Army Vehicles Crossing the Completed Teal Low-level

Bridge at t he En d of J an ua ry 195334. Teal Bridge Underwa ter on 15 J uly 195335. The Im jin River Flowing 12 Feet Over th e Teal

Bridge on 15 J uly 195336. Teal Bridge in Operat ion on the After noon of 16 J uly

1953 After Floodwater Receded37. Teal Bridge After the Flood of 15 J uly 1953 Showing

Minor Damage

Figures 38-63, relating to the construction of Libby bridge, appear between pages 54 and 68:

38.

39 .

40 .

41 .

42 .

43.

44 .

45 .

46 .

47 .

48 .

49 .

The Imjin River a t the X-Ray SitePile Driving on Cofferdam 1 Dur ing Februar y 1953Excavat ion of Cofferdam 1 and P ile Dr iving on

Cofferdam 3Cofferda m 3 Filled With 240 Cubic Yards of Concrete

Const itu ting th e Initia l or A PourInterior View of a Cofferdam Showing 12-inch

H-beams, or Whalers -

The Cent ral Concrete Batch P lant on t he Im jin’sWest Bank Close-up View of the Concrete Batch PlantThe 34 E Paver and Rex Pu mpcrete MachineForms for D Pour That Had Been Pu t Together on t he

Ground, Raised, and Then Lowered Onto the CPour Pedestal

The Cur ing Cabin on Pier 7 in Position for t he F ina lor E Pour

Steel Mat s That Would Reinforce the Br idge DeckingBeing Fabricat ed in t he Cent ra l Work Yar d

Soldiers Cast ing Gua rdr ail Posts

xii



Fig. Page

50. Fu ll-scale Model of a Section of Decking Tha t WasBuilt in the Work Yar d for Pr actice and TestingPurposes

51. Riveter s at Work on St eel Beams52. Steel Beams Being Prepared for t he Span Fr om theWest Abutment to Pier 7

53. Steel Beams in P lace l+om th e West AbutmentAcross P ier 8 to Pier 7

54. Launching the Span Across Piers 7, 6, an d 555. Cha in Hoist Lowering Girder Complete With Sub-

decking Across P iers 7, 6, and 556. Close-up View of Cha in Hoist Lowering Downstream

Girder Across P iers 7, 6, and 557. Troops Sett ing Up the Pumpcret e Pipe To Pour

Concrete Decking58. A Bur lap Drag Being Used To Give th e Deck Su rface

the Desired Rough Texture Perpendicular to Traffic59. Concrete Deck Being Covered With Bur lap P rior to

Receiving a Seven-day Water Cure60. Completed Libby Bridge Fr om the West Bank on 4

J uly 195361. View Looking East a t t he Completed P iers and Su -

perst ructure of Libby Bridge62. Libby Bridge With standing the Flood of 15 J uly 1953

With More Than 20 Feet of Clear ance63. Plaque Erected at th e East En d of th e Bridge as a

Memorial to Engineer Sergean t George D. Libby

64. Major William C. Car ter, J r ., in Front of the LibbyBridge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10365. Excavat ion of Cofferda m 6, Begun by a 3/4=yard

Clam Bucket on 16 January 1953 . . . . . . . . . . . . . . . 10966. Work Cont inuing on Piers 1, 2, and 3 F rom

Submerged Ea st Causeway During High Tide on17 Ma rch 1953 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122

67. Storm Wat er a nd a Spring High Tide Combined To

Force an Evacua t ion of the Causeway on 20 March1953 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...12468. Ea st Abut men t Pr ior t o Str ipping of Forms . . . . . . . . . 12469. Completed Piers 7 and 8 in Lat e March 1953 . . . . . . . 125

. . .Xl11





B R I DG IN G T H E I MJ I N

CONSTRUCTION OF LIBBY AND

TEAL BRIDGES

DURING THE KOREAN WAR

(OCTOBERl952-JULY 1953)



Korea

I August 1952127O E

I

I127O E

38’ N

MAP 1



Introductionby Charles Hendricks

The Imjin River rises h igh in the Taebaek ra nge along Korea’seastern coast line. (Map I) Sta rt ing its jour ney less than 20 miles

west of the important North Korean port of Wonsa n, it flows souththrough the rugged central portion of the Korean peninsula,gather ing with it the wa ter s of the Komit ’an , Yokkok, an dHan t ’an rivers before t urning southwest at the 38th parallel to

join t he H an River as it a pproaches the Yellow Sea. While th eImjin appears no more than a sluggish st ream dur ing much of theyear, the monsoon r ains that mark the Korean summer regular lytr an sform it int o a mighty torr ent during J uly an d August .

The lower reach of the Imjin, stretching from the confluence of the Yokkok to the Han , gained considerable military significancedur ing the last two year s of th e Korean War . In th is period th ewestern end of th e main ba tt le line between the United Nat ionsand Communist forces stabilized along the plains and h ills a fewmiles west a nd n ort h of th e river. fiorn the crossing of the lowerImjin by Amer ican -led U.N. forces in J une 1951 until the signingof the ar mist ice on 27 J uly 1953, the vagar ies of the Imjin’ssummer floods, aut umn calms, wint er freezes, and spring th aws

posed cont inuous challenges to the Army engineers responsiblefor maint aining passa ge across its water s.

-2

This volume tells the story of th e cons t ruction dur ing late1952 and ea rly 1953 of two bridges across t he Imjin. Both r epre-sented innovative approaches to the problems posed by the river.The modern, high-level Libby highway bridge supported on con-crete piers an d abu tm ent s an d the submersible, low-level Tealbridge built on 164nch steel piles were novel solut ions to bridging

requirement s locat ed so near a bat tlefront. The building of th esebridges clima xed a pr eliminar y 15-month cont est between t heArm y engineers an d the Im jin, during which th e engineerslear ned t he devastat ing power of th e river a nd began to devisesolut ions to its cha llenges.



4 BRIDGING THE IM J IN

The engineer confront at ion with th e Imjin began after th e1951 Commun ist spr ing offensive groun d to a ha lt short of Seoulin May. United Nations forces on the western side of Korea led by

Major General F’ r ank W. Milburn, commander of the U.S. Army’sI Corps, quickly resumed t heir advan ce, retook Uijongbu on 6May, an d reached th e Han t ’an River on th e 25th . Thr ee dayslat er, I Corps’ 58th Engineer Treadway Bridge Company bridgedthe Han t’an nea r where it flowed int o th e Imjin. The 408footfloat ing bridge built by the company supported the advance of the1st Cava lry Division.’

The same compa ny, aided by elements of I Corps’1092d Engi-neer Combat Bat ta lion, began on 6 J une to const ru ct a 492.footM-2 float ing t r eadway bridge across the Imjin roughly 8% milesto the northwest. Designed to support the drive of the British 28thIndependent Brigade, then attached to the 1st Cavalry Division,the br idge’s ponton rafts had to be assembled one-half mile down-stream from the bridge site and then towed there by amphibioustrucks (DUKWs), ut ility boat s, and ma npower. Constru ct ion wasinterr upted by enemy mort ar fire around dark an d was not corn-

pleted until early the next afternoon. It was named the Corporal

Wright bridge in h onor of Corporal Theodore Wright of the 58thEngineer Company, who died of wounds received during its con-s t ruc t ion2 (Figure 1) (Map 2)

During June, United Nations troops pressed their advance inth e moun ta ins east of th e Imjin an d north of th e Han t’an butun dertook only ra ids and pat rols west of th e Imjin. In makingthese raids, the U.N. forces relied upon float ing t readway bridges,50-ton capacity ferr ies, and footbridges inst alled at three sites on

the lower Imjin. The Corporal Wright br idge was r eplaced by aferr y and a footbridge on 26 J un e; an oth er ferry and footbr idgewere installed 8% miles north a t what would become kn own asth e Whistler site; an d dur ing 20-22 J un e th e 58th En gineerCompa ny a nd Compa ny A, 14th En gineer Combat Batt alion,inst alled a second M-2 steel t r eadway bridge 16 miles southwestof the Corporal Wright bridge at what the Americans would latercall the Honker site. This last bridge stood astr ide the ma in road

from Munsan -n i to Kaesong, Korea’s medieval capita l, and itenabled a tan k a nd infan try force of the Republic of Korea’s 1stDivision to stage a su ccessful ra id on Kaesong3

Because of the danger of a new enem y offensive, I Corpsengineers r emoved the Honker br idge only four da ys after its



The lmjinRiver Bridges

1951-1953

30’ N

’ Widgeon

X-Ray(Libby)

lTongduchon-ni

lUijongbu

MAP 2



6 BRIDGING THE IMJIN

completion an d r eplaced it with a ferr y. Even fart her down-str eam, the Korean division in late J un e blew a 234-foot gap inthe Ch inese-built r ailroad bridge on t he ma in rail line fromP’yongyang to Seoul. The Korean s a cted on the orders of the ICorps engineer , Colonel Emerson C. Itschner , a man who wouldlat er become Chief of Engineers . But when the Comm unist sproposed to hold peace ta lks at Kaesong, the companies that hadconst ru cted th e J un e bridge at th e Honker site built an oth erfloating bridge there on 2 July to accommodate U.N. delegates tothe forthcoming conference. (Figure 2) This time they employed amobile cran e and a plat oon of dump tr ucks to build up the northshore appr oach r oad to protect it from h igh water.4

The United Nat ions forces were thus opera ting thr ee crossingpoints on t he Imjin when the 1951 ra iny season began in earneston 19 J uly. I Corps measured 5.22 inches of ra in in t he 48 hoursbeginning at noon that day, and by 21 J uly the Imjin had risen to11.8 feet. The 1st Cavalry Division’s 8th Engineer Combat Bat-talion attempted to remove the Whistler footbridge, but began toolat e and lost one-third of it. The footbridge at the Corporal Wrightsite wash ed out completely. One sect ion of footbr idge slammed

into th e ferry at th e lat ter site an d sent it a mile downstr eam.Togeth er with a disabled DUKW and other debris, the runawayfootbr idge then float ed all the way down to the Honker site whereit h it and bent th e floating bridge, put ting it out of service forthr ee days. Colonel It schner observed, “A lesson learn ed duringth is la test period is th a t n o floa ting equipment is dependableunder h eavy flood conditions with la rge quant ities of debris.“5

American engineers constructed a new footbridge and ferry at

Whist ler in lat e July, but more high wat er on 1 August wash edthem out . Nevertheless, corps engineers began the more ambi -t ious task of building a float ing t readway at th e Whist ler site onthe very same day. Although they had to suspend work for a timebecause of the flood, th ey managed to complete a 600-foot-longbridge by the morning of 3 August , when tanks of the 1st CavalryDivision r umbled across in an offensive dr ive. (Figure 3) The fat eof this bridge was typical of I Corps’ problems with the Imjin tha t

August. High water two days later forced the engineers to swingth e bridge to shore, and the r eceding r iver left it h igh up on thebank. Rebuilt on 6-7 August , th e bridge was finally disman t ledon 9 August during a n ew flood?

The flood of 1 August also swept a way the Honker floa t ing



INTRODUCTION 7

tr eadway. American engineers rebuilt it over the next two daysand then swung it to shore du ring t he floods of 5 and 9 August .But the bridge broke loose from its anchorage at 11 AM on the 9th

and floated all the way down to the Yellow Sea, despite the effortsof amphibious engineers to recover it. Eighth Army’s 84th Engi-neer Const ru ction Bat ta lion r ebuilt t his bridge during 12-16

August but took it down t hr ee days later in th e face of typhoonwarn ings. After the storm tu rned away from Korea , the bat ta lionrebuilt th e bridge again on th e 26th an d 27th. A day after itscompletion, new floodwaters once more destroyed the bridge.7

Fortunately for the engineers, enemy action that summer didnot mat ch the ferocity of the r iver. Observing again tha t “keepingfloat ing bridges int act during heavy flood periods is an impossibleta sk,” It schner was grat eful t ha t “th e ser iousn ess of the floods[was] reduced great ly by the quiet t actical situ at ion; dur ing amore active and operational period such floods could have provendisast rous t o th e UN troops.“8

Short ly after the 1951 flood season ended in lat e August , ICorps push ed ma jor elements across th e Imjin River. The offen-sive began 7 September when a bat ta lion of th e 1st Comm on-

wealth Division advanced to Chalmul. t ie more battalions of thisdivision an d element s of the 1st Cavalry Division crossed th er iver th e following day, advancing t o a new Line Wyoming thatran west of the Imjin from Korangpo-ri northeast throughChalmul and Kangso-r i .g

The 58th Engineer Treadway Bridge Compan y and the 14thand 1092d Engineer Combat Batt alions built th ree M-2 float ingtreadways across the Imjin on 8 and 9 September to support th is

advance. The 396-foot P in t a i l bridge just 2% miles below theImjin’s confluence with t he Han t’an an d the 456,foot Teal bridge4 miles far th er southwest su pport ed the advance of th e 1st Co r n -

monwealth Division. At Whitefront , lV4 miles north of the oldCorpora l Wright site an d 3 miles north east of Pinta i l , th e engi-neers completed a 540-foot float ing bridge just before midnight on9 September. These engineer units built a four th float ing t read-

way across th e Imjin, th e Widgeon bridge, on 20 September.While this bridge was only two miles southwest of the Teal bridge,the broad northwesterly bend in the Imjin between Widgeon andTeal jut ted so close to Line Wyoming that supplies could not besafely tr an sport ed on t he Imjin’s west ban k between the t wobridges. lo




After a brief respite, I Corps pushed its limited a dvance for-ward another t hr ee to four miles to Line J amestown in October.(A&. 3) This new advance moved the Republic of Korea’s 1stInfant ry Division a cross the river and push ed the 1st Common-wealth Division comfor tably beyond it . The Korea n division’smovement crea ted a need for more bridges across the lower Imjin.I Corps engineers bu ilt a footbridge at Korangpor i , th ree milesdownstream from Widgeon, in early October and replaced it witha causeway later in the month . They built a float ing t r eadway atthe X-Ray site three miles farther south and a floating footbridgesix miles below Korangpo-r i on 18 and 19 October?

On 23 Oc tobe rY two days before t he r esumpt ion of ar mist ice

ta lks at Pa nmun jom, the 84th Engineer Const ru ction Bat ta lionrebuilt the Honker floating t r eadway bridge to facilitat e access toth e tr uce talks. The Honker br idge was locat ed just 1% milesbelow the footbr idge th a t the Repu blic of Korea’s 9Olst LightPonton Compa ny h ad inst alled 6 miles sout h of Kora ngpo-r i.Honker adequa tely served th e a r e a . 1 2

As th ere were no bridges int act downst ream from Honker , ICorps ordered the Korean company to remove the footbridge and

transport it 3% miles west of the Honker crossing to what wouldbe called the Freedom Gate site. There, alongside the remains of the low-level railroad bridge that their countrymen had severedin J un e an d the h igh-level rail crossing tha t ha d been brokenearlier in the war , the 9Olst Company at the end of October twicemore la id the footbridge across the Imjin. Each time, the powerfulcur rents of a ten-foot tide washed it out . Colonel Edward Daly, thenew I Corps engineer, finally conceded the impossibility of main-

ta ining a float ing r bridge t h e r e . 1 3With wint er approaching, I Corps engineers considered a lter-

na tives t o th e float ing bridges. Beginn ing in September , theylooked for appropriate sites for pile bridges. They knew that “if ICorps was successful in staying across the Imjin River9 that t heseperm an ent bridges would be required to reduce the danger of flood a nd ice dest roying th e M-2 bridges.“14 .

Not enough perm an ent pile bridges could be constructed be-

fore ice filled the Imjin, however. So in early November the ngi-neers decided to replace the floating bridges with low-level fixedbridges that could be constructed quickly. In shallow water, ock-filled crib piers would support the span. The engineers would usepile piers where the river was a t least th ree feet deep. In eith er



Battlefrontin Western Korea

31 October 1951

1 10 km. I

&Whitefront _

X 9 ROK

., 1 Cavalry X

1 ROK X 1 Commonwea l th x

XI

Honker

l Munsan-n i

* *

l Ui jongbu

127’ E

MAP 3




case, th e br idges would have a m odified M-2 t r e adway deck suitable for tanks and a minimum clearance of five feet above lowwater. The approaches might include cau seways to reduce thelength of th e bridge.15

The 72d En gineer Combat Compa ny built t he first bridge of this type. This five-span, 150-foot crib-pier br idge at tached to alonger cau seway crossed at th e nort her nm ost Whist ler site,where only a ferry had operated since the removal of the floatingt r eadway bridge dur ing th e flood of 9 August . Corps and armyengineers insta lled other low-level fixed br idges a t th e White-front , X-Ray, and Widgeon sites in la te November and December1951. (Figures 5 CUZ~ 6) The 62d Engineer Const ruction Batt alion

completed the new X-Ray bridge on 26 December, only five daysbefore ice dama ged the float ing bridge th ere a nd forced its r e-

moval?

Spann ing the Imjin a t t he F’reedom Gate site closest to itsmouth proved to be difficult. After the effort to install a floatingfootbridge there failed at the end of October, the1092d EngineerCombat Bat ta lion proposed a suspension bridge connecting diag-

onally the t wo high-level ra ilway spans, the cent ral port ions of

which had been demolished. I Corps instead ordered the battalionto build a 1,450-foot-long and 20-foot-high pile footbr idge justupst ream from the destr oyed ra ilroad bridges. But a s LieutenantColonel Andrew Inge of the 1092d complained during cons tr uc-t ion, “The design [of this footbridge] had been cut to the bone toredu ce the nu mber of piles an d ma ter ials. . . . This resu lted inpract ically no safety factor.“17

Work on this pile footbridge proceeded slowly dur ing Novem-

ber u nt il an embarr assing mishap inter ru pted const ru ction onth e 30th . Tha t evening a work crew left a ra ft, bear ing a crawlercrane tha t it used as a pile driver, anchored in sha llow water. Thereceding tide beached th e ra ft on the sloping riverbed, an d thecrane, which was not secur ely fastened, slid off into the muck. Afive-day recovery effort, assisted by Navy divers, retrieved avir-tua lly useless piece of equipment . Work resumed under st ricteroperating procedures on 10 December with a crawler rig borrowed

from Eighth Army, and the footbridge was completed on 2.1 De-cember. By then ice had begun to appear on the Imjin, and on 4January heavy floes carried by a strong tide destroyed a 160.footsect ion of the br idge?

A week before the destruction of the Freedom Gate footbridge,



INTRODUCTION 11

ice had broken the Honker floating t r e adway in two. The twolosses left a cons idera ble st retch of the lower Im jin without abridge and provoked a flur ry of activity among corps and ar myengineers. The I Corps engineer immediat ely had a 400.pound

expedient cableway insta lled at t he Fr eedom Gat e site an d or-dered th e 14th Engineer Combat Batt alion to build a diagona lquart er-ton capacity suspension bridge between th e broken high-level ra ilway spans there. The Eight h Army engineer ordered his84th En gineer Bat talion t o const ru ct a low-level steel- an d t im-

ber-pile bridge near by. The bridge would st and on 30 steel bentsin the main r iver channel and 66 t imber bent s on t he r iver’s edgesand t idal flats. The bat ta lion was required to build a deck suitable

for both highway an d rail traffic.lgAssigning two companies an d devot ing over 140,000 man-

hours to th is project, the bat ta lion made rapid progress a nd wasable to open the bridge on 1 5 February. (Figure 7) Six days lat erfriendly aircraft mista kenly bombed th e bridge and dam agedseven bents. The 84th r eplaced all of the damaged bent s exceptone which stood dangerously close t o an un exploded l ,OOO-pound

bomb tha t could not be removed. Tha t a rea was spann ed by a 36.

inch I-beam suppor ted on specially bra ced bents.2oThe br idge-building success of the 84th at Freedom Gate ledth e I Corps engineer to suspend work on th e light suspensionbridge th ere on 4 Februar y 1952, when it was 61 percent corn-

plete. Toward the end of tha t mont h, I Corps built one more br idgeacross the Imjin fart her nort h than the other available crossings.This was a 168foot-long rock-crib bridge three miles north of theWhistler bridge at th e Mallar d s i t e . 21

Although well suited for the river’s ice, neither the low-levelbridges on r ock-cr ib piers n or t he one atop pile piers a t t he oldFr eedom Gat e ra ilway crossing could be expected to withstandthe Imjin’s summer floods. The September 1951 surveys had beendesigned to locat e sites for perman ent high-level crossings, andby the end of October, planning ha d advan ced su fficient ly topermit the 84th Engineer Const ru ction Batt alion to begin work at Pin t a i l on a timber-bent bridge support ed on pile piers th atwould st an d 43 feet a bove mean low water. The r iver was onlyabout 420 feet wide at th is point , but t he bridge was designed tohave a length of about 1,000 feet to connect the river’s banks at itsown height . 22

After th e 58th and 72d Engineer Companies moved the Pin-




tail float ing t readway to make way for the new h igh-level cross-ing, the 84th Engineer Batt alion found tha t the rocky river bot-tom there prevented the sinking of t imber or steel piles. Seeking asecure crossing of the Imjin without delay, Eight h Army engineer

officers quickly ordered the battalion to construct at the Teal sitea bridge very similar to th e one planned for Pin ta i l . The Tealbridge was a one-way, 50-ton-capacity timber-trestle bridge thatwas 1,175 feet long a nd 48 feet h igh. (Figure 8) Timber pilessupport ed the ten sout hernm ost bent s while steel piles car riedthe weight of the three bents to the north. The battalion finishedth e bridge on t he last day of 1951, after investing 137,000 man-hours in its construction.23

In order to prepare more adequately for the summer floods,Eighth Arm y in Februa ry 1952 assigned its 62d Engineer Con-st ru ction Batt alion t o widen and r aise th e X-Ray bridge and tobuild a new high-level bridge on concrete foundations at Pintai l ,where the 84th’s ear lier effort s had been abort ed. Company C of the 62d undertook both assignments in March after the r iver’s icemelted. Dr iving new piles and constr ucting timber bent s, thecompan y made ra pid progress at t he X-Ray site. In mid-Apr il it

installed the 24.inch I-beams t ha t would car ry the decking. Thebridge opened to traffic on the 27 t h . 2 4

The Pin ta i l bridge progressed more slowly. Company C of the62d pour ed th e concrete foun dat ions in lat e April an d inst alledthe steel pile and rein forcing rods in ea r ly May. The companylaunched the bridge’s 48inch I-beams in late May and J une andpour ed the concrete decking in J uly. The br idge opened on 24J uly, just days before th e disast rous flood of 30 J uly 1952. Like

the X-Ray bridge, Pin t a i l was designed t o ha ve a 50-ton capacityas a two-way br idge or to suppor t 80 t ons one way . 25 (Figure 9)

As the 62d began work on the new X-Ray andPinta i l bridges,th e 84th En gineer Const ru ction Batt alion began a high-levelbridge of similar capa city at th e Whitefront site. The bridge was1,184 feet long and stood 44 feet above low water on 13 timbertr estle bent s support ed by steel piles. (Figure IO) Timber pilingwas t ried, but it would not penetr at e adequat ely even when a pilesh oe was u sed. Com pa ny B of th e 84th com pleted t he br idge by theend of May, investing 111,000 man-hours in its construction.26

After reopening t he low-level ra ilway bridge at th e Fr eedomGate site, the 84th also began building a high-level Imjin crossingadjacent to it. The new bridge u_ t i l i zed th e rema ins of th e more






















souther ly of the two ear lier r ailway bridges at the site. One of theconcrete piers of th is bridge had been destroyed, and the bat talionhad to replace it with a pier comprised of a wooden-pile bent

cluster an d prefabr icat ed steel tr estle. In a ddition t he west-ernm ost span h ad t o be replaced and a nother spa n jacked andrebraced. The engineers cont ra cted with th e Korean Nat iona lRailway to assist in the work. On 5 J uly the batt alion launched a206=foot=long, 4%inch I-beam across t he n ew pier from one origi-nal concret e pier to an other . (Figure 11) Completed soon after ,this second high-level bridge was opened and dedicat ed on 17

J uly, just before t he s tar t of the 1952 flood season.27

I

After th eir exer tions of the pr evious m ont hs , the engineer swere shocked by the destructive intensity of the 1952 floods. Theflood season began early as April precipitation exceeded thatrecorded in the four th month of an y of the pr evious 30 year s.Floodwater s on 13 April wrecked th e nort her ly Mallar d an dWhistler rock-cr ib pier br idges, and nea rly topped th e low-levelWidgeon bridge well downst ream. I Corps engineer t roops r e-placed th e Mallar d crossing with a new 300.foot-long bridge thatwas six feet h igher than th e old. They raised the Widgeon bridge

by four feet a nd drove ra ilroad ra ils above it for an upst rea mfender a nd an chor system.28

Heavy ra ins at t he end of J uly raised the level of th e Imjin by13 feet on 27 J uly, causing the new Mallard bridge to collapse andforcing the removal of the Honker float ing tr eadway. The rainscont inued for t he next t hr ee days, and by 30 J uly the Imjin atPinta i l had risen 38 feet. At n oon tha t day, after r iver cur rents asfast a s 15 to 20 feet per second had exposed the base of some of the

piles supporting the Teal bridge, two of the bridge’s spans washedout . Debris from Teal washed downst ream to X-Ray, where itstr uck a br idge th at ha d a lready been m oved about four feetdownst ream by the floodwaters. t ie pier s of the X-Ray bridgefailed at 1:30 PM. (Figure 12) Debris also lodged against the high-level Freedom Gate bridge near the r iver’s mouth , leading theengineers to close it for four hours on 31 July while they removedth e debris with a crane.2g (F igure 13)

The low-level Widgeon bridge submerged on 27 J uly and re-mained intact under some 20 feet of water. It r eappear ed on 3August after th e floodwaters passed, requiring only minor re-pairs. The success of the Widgeon bridge impressed ColonelMer-



INTRODUCTION 23

row Sorley, I Corps engineer, who concluded t hat “this type of bridge has fut ur e poten tialities. . . . [It] is not an equal substitu tefor a permanent high-level bridge over which traffic at all seasons

will be as assu red as it is tact ically indispensable; but as a re la-t ively cheap br idge, which m ay prove usa ble much of the yearwith only minor periodic damage and repair, it appears from th isrecent t est to have demonst ra ted value as a su pplementa lbridge.“3o This lesson was instr ument al in determining the de-sign of th e submersible Teal bridge const ru cted tha t aut um n.

An even great er flood roar ed down t he Imjin on 24 a nd 25August, fed largely by rains that fell in North Korea. Raising the

Imjin 40.5 feet in ten hour s at Pintai l , these waters destroyed th eWidgeon bridge and swept away addit iona l piers of the Teal andX-Ray br idges. (Figure 15) This was the year ’s last significan tflood on the Imjin. At the end of the 1952 flood season, t he I Corpsengineer observed with some sa tisfaction th at th ree high-levelbridges-at Whitefront, P in ta i l , and Freedom Gate-had sur-vived th e summ er unscath ed, an d each su pport ed a differentdivision across the river. (Figure 16) But m ore t ha n 16 milesseparat ed the F’ reedom Gate and Pinta i l bridges, an d th is str etchof open river could have threatened the U.N. forces if the enemyhad launched a serious offensive in August 1952 . 31

The need for br idges in tha t r each of the Imjin led I Corps toinstall new float ing t r eadway bridges at the X-Ray and Teal sitesin September and t o build a rock-crib pier bridge at the nat urallydefiladed Spoonbill site thr ee miles south of the X-Ray crossing.(Figure 17) With its piers st rengthened by piles ma de from rail-way r ails, th e Spoonbill bridge opened to t raffic on 30 Oc tobe r . 32

But th ese bridges too would be temporar y, an d th e need to con-struct permanent bridges to replace the two high-level crossingsthat had been destroyed by the summer floods of 1952 remained.Eighth Army’s 84th Engineer Constr uction Battalion u nder took the job, constr ucting a submersible, low-level bridge at the Tealsite and the h igh-level, steel an d concret e Libby bridge at theX-Ray site. Standing 49 feet above mean low water, the Libbybridge remains in u se today. (Figure 18) The Teal br idge provided

eight years of useful service before it was removed in late 1961. Itwas replaced the following spring by a new low-level bridge madeof reinforced concrete. These su perb war t ime br idges were r e-

spon . ses to a r iver- ‘crossing problem that had faced th e American




engineers for more than a year. Enriched by their experience,

th ey finally resolved th at problem in th e last month s of th e war.

For two years the Imjin proved itself a worthy opponent to the

American military engineers.



CONSTRUCTION OF LIBBY ANDTEAL BRIDGES,

IMJIN RIVER, OCTOBER 1952 TO JULY 1953

bY

William R . Far quha r , J r.

and Henry A. Jeffers, Jr.



Preface

Between October 1952 an d J uly 1953 two bridges of un usua ldesign were built over th e Imjin River in cent ra l Korea with inra nge of th e enemy’s light ar tillery. One was a high-level high-

way bridge which would be a credit to any sta te h ighway systemin the United States; the other was an experimental “low-water”bridge which is expected to survive being submerged by the riverwhich it spans. This monograph explains why these bridges werebuilt, and presents some of the problems which had to be solved,obstacles overcome, and hardships endured by the 84th EngineerConst ru ction Bat ta lion th at built them.

The narrative is written to be understood by the professionalsoldier who may have litt le or no knowledge of engineer ing and itsspecial language. For the engineer, however, who might be inter-ested in the technical aspects, many of the engineering deta ils ar eincluded in t he su pporting documents. In addit ion, completed “as-

built” t racings of the high-level br idge (Libby) have been for-warded to the Engineer School, Fort Belvoir, Virginia, by the 84thEngineer Const ruct ion Bat talion. 1

The initial resear ch and r ough draft of th e nar ra tive weredone by Major William R. Farquha r , J r. After his depart ur e from

th is organizat ion t he project was completed and pu t in fina l formby Major Henr y A. Jeffers , J r.

When this project was reviewed by the Commanding Officer,2d Engineer Construction Group, he suggested that a resume of th e designing pha se of the two bridges might be of interest toother Army Engineers. This informal resume was pr epared by hisheadquart ers and is att ached.

Seoul, Korea21 September 1953



CHAPTER I

Background

The Imjin River, a t ribut ary of the Han, flows in a meanderingcour se a short distance sout h of a 25mi le- long str etch of th e

stabilized main line of resistance of the United Nations Forces inwestern Korea . Its presence close behind t he line, between t hefront line t roops and their sour ces of supply (an d in some casestheir ar tillery), grea tly enhances the importance of the crossingsavailable. .

Seen for the first time during normal weather conditions, theImjin is not a par ticularly impressive river; it can be forded easilyin ma ny places. Its active cha nnel ut ilizes only about 150 to 200

feet of the 1,200-foot width of the dry riverbed, which is borderedby almost ver t ica l rock cliffs st anding appr oximately 75 feetabove the mean low water level. It gives no indicat ion in normalt imes of th e tremendous power it develops when in flood.

During the Korean ra iny season of Ju ly and August , the Imjinbecomes a raging torrent, largely confined by its steep rockybanks. Fed by its lar ger t ributar ies and m an y small moun ta instreams, it reaches flood heights of 48 feet above mean water leveland a velocity of 15 to 20 feet per second. The r apid runoff of approximately 95 percent of precipita tion du ring heavy generalrains ha s cau sed th e Imjin, on occasion, to rise a t a ra te of moreth an six feet per hour?

In a ddition t o th ese extr eme var iat ions in th e amount andspeed of the wat er, th e riverbed it self sh ift s an d cha nges witheach seasonal flood. The sand, gravel, silt, and boulders, whichform the movable mater ial (overburden) in the r iver bott om, ar escoured out of their r est ing places by the force of the flood and

deposited again wherever the eccentricities of the river currentsdicta te. Specific inform at ion as to the degree and nat ur e of th emovement of the Imjin River’s overburden is not available. How-ever, the experience of Japanese and Korean bridge builders, andtha t of the Corps of Engineers a fter two year s in Korea , indicat esthat the overburden is unstable to a depth equa l to the depth of th e water in t he st ream, or t o bedrock, whichever is less.2




During the severe Korean winter, icy winds sweep down theImjin; the sub-zero temperat ur es cau se th ick ice to form on t heriver. Fluctu at ions in the level of th e river , par ticula rly tidalaction in t he lower reaches, break up t his ice, and large amoun ts

of floe ice pile up against any obstacle in the channel. The destruc-tive force exerted by the floods and ice of the Imjin has made theta sk of th e engineers r esponsible for bu ilding and ma intainingbridges on the Imjin a most difficult one.

Dur ing the flood season (1 July to 15 September) and the iceseason (15 December to 25 March), float ing br idges cannot beused because they cannot stand th e unusually st rong force of th ewater or t he pressure of th e ice. Neither can ordinar y milita ry

bridges of the r igid type withstand the pressur e of the Imjin floodplus th e impact of tons of debris, including par ts of our own andenem y washed-out bridges which come float ing down a t h ighspeeds. 3

In July of 1952 there were five high-level bridges on the Imjinwhich were expected to provide communications with the I Corpsfront during the flood season. * These were, from north to south:

(1) White f ron t -a two-way, high-level bridge supported by

t imber bent s on st eel piles (CT 260133, Map: Korea 1:25;000).(2) Pa rker Memorial (Pint a il)-a two-way, h igh-level bridge

supported by steel piers on concrete bases (CT 231097).

(3) Teal-a one-way, high-level bridge supported by t imber-pile bent s (CT 175057).

(4) X-Ray-a two-way, high-level bridge support ed by t im-ber-pile bent s (CT 097012).

(5) Freedom Gate (M unsan-ni)-a reconstructed high-level

ra ilway an d road bridge on concrete piers an d one, light , steel-tr estle pier (CS009955).There were also in the I Corps sector several floating bridges

an d one low-level bridge; these were not expected to be usabledu r ing t he flood season . Widgeon , th e low-level br idge (CT151035), is of interest, however, in that it was expected to surviveth e floods even though su bmerged. It was a t r e adway bridgesupported by rock-filled cribs; this was t he first at tempt to build acheap low-level bridge that would survive being submerged byth e floods and provide a crossing dur ing the rest of the year .

I Corps Headqua rt ers was fully cognizan t of th e thr eat th atthe Imjin presented to the lines of communication to the front inits sector. An operational flood plan was prepared “which a s-



CONSTRUCTION OF LIBBY AND TEAL BRIDGES 31

signed r esponsibility to individual unit s for commun icat ions andprocedur es for repor ting river r ises, for facilities n ecessa ry toprotect bridges such a s debris booms, LCM’s [lan ding crafts,mechanized] and u tility boat s, for searchlight illumina tion to aidin night removal of debris, and for t an ks or au tomat ic weaponsfire to brea k up floa t ing debris.“5

The flood season was lat e in gett ing sta rt ed in t he summer of 1952. It was on th e 27th of J uly that the first of th e Imjin floodscame, a minor rise which overtopped Widgeon bridge and wash edout its approaches but did not otherwise dama ge it. However,heavy genera l rains on t he wat ersheds of th e Imjin a nd t heHa nt ’an , the Imjin’s ma jor tr ibut ar y, dur ing the night of 27-28

J uly and on 28 July presaged a more formidable rise. At Pa rkerMemorial bridge the river rose 38 feet during the per iod 5 AM on27 July to 3 PM on 30 July. Complete dat a a s to flood heights at allbridge sites a re not available due to th e fact tha t flood gaugeswere in many instances a ffixed to the bridges and thus w&t downthe r iver with t hem; but of par t icula r int erest is the followingfrom the “Flood Report, 1 July-15 September 1952,” Office of theEn gineer, Headquar ter s, I Corps, 26 September 1952:

After a rise of 27 feet a t Teal . . . two spans failed and were washedout at 1200 hours on 30 J uly. Failure of th e bridge occur red when litt ledebris was present in the channel, nonehung on theprevious observable displacement of the structur e h a

piers,.d occu

and when norred from the

st r iking of debris. Deb& was not a primary or seconda ry cause of fajlurewithin the observation of spectat ors . Pr evious pile penet ra tion of ten feetha d been reduced to as litt le as t wo feet on some piers by scour act ion.Nine piers were scour ed at th e base but oth erwise still in good condit ion.Three piers were completely destr oyed by th e flood. Maximum velocitiesobserved upstream were a s great as 15-20 feet per second in t he deepestpar t of th e river? .a

At 1330 hour s 30 J uly 1952 the X-Ray t wo-way h igh-level bridgefa iled when t wo piers went out . Str iking of debris was a cont ributingcause of failure of X-Ray, when it was st ru ck by large float ing segmentsof crib a nd floor debr is from th e fa ilure of Teal. This occurr ed slight lybefore the crest ing of the flood a t X-Ray, at a river stage about one footbelow crest height . At t his t ime, however, a port ion of X-Ray bridge hadalready been displaced downst rea m about four feet from a pr imary

cause which might have caused failur e even in t he absence of debris, andwhich wa s presum ably sliding of pile bent s.’

.

Freedom Gate (Mun s a nn i bridge) and Widgeon held up well




dur ing this flood. Freedom Gate was closed to traffic for only fourhours on 31 J uly so that a crane could be moved onto the bridge toremove debris lodged against the piers. Widgeon, overtopped bythe flood, reappeared int act when t he wat er su bsided and wasreopened t o tr affic on 3 August after minor r epairs.

The Imjin r emained fair ly quiescent un til 24 August whenconsiderable ra in fell to the north and east of the I Corps sectorprior to 6 AM. At t ha t t ime both th e Imjin a nd H an t’an riverssta rt ed ra pid rises where th ey enter ed U.N. territory. At th ePa rker Memorial bridge the river rose 40.5 feet between 7 AMan d 5 PM. Dur ing this flood Widgeon bridge was almost com-pletely destroyed and X-Ray bridge lost five more spans. “At

various times . . . Parker, Whitefront , an d FYreedom Gate bridgeswere closed to traffic for short periods to enable debris removaloperat ions to be facilitat ed. Accumu lat ion of debris against th etimber pile piers combined with high river velocities constituted acont inual hazard necessita ting debris removal. The cont ent of thedebris indicat ed that th e enemy ha d suffered dam age to his in-stallat ions and a lso that the neighboring Corps had some losses inbridge and ferr y equipment .“8

In ea r ly September float ing bridges were placed at Teal andX-Ray sites, and a ferr y was operat ed at Widgeon site as neces-sary. (Figure 19) The Imjin flood season of 1952 was over, and thecent ral port ion of the I Corps sector was left without bridges thatcould withstan d t he ice season which would begin in December.

The Comman ding General, I Corps, felt tha t replacement of Teal and X-Ray bridges was a n urgent military necessity and soinformed th e Commanding General, Eight h Army.g He also rec.

ommended that more substan tial structu res be built, rather thanrestoring the structures which had proved inadequate in the faceof high wat er. In a later commun icat ion, it was point ed out tha tthe float ing bridges at these sites would have to be removed about11 D , e c embe r to prevent unnecessary loss of equipment dur ing theice season and tha t it would be highly desirable that permanents t ru ctu res be com pleted at th ese s ites pr ior t o th at t ime in order toprovide continued satisfactory support of the forward elements of I Corps. lo The Eight h Army Engineer inst itut ed an extensive

stu dy and resear ch progra m t o provide a basis for design andconst ruct ion of bridges capable of with st anding th e floods andunusu al river condit ions encoun ter ed on t he Imjin?

Arm ed with t he basic da ta a nd specificat ions fur nished by




Eighth Army an d supplement -ing th is with resea r ch of itsown, the 2d Engineer Const ruc-tion Group proceeded with thedesigning of suitable bridges tomeet these needs.12 Confer-ences between the EighthArm y and I Corps E ngineersled to an inform al agreementon th e const ruct ion of a two-way, high-level bridge at X-Raysite and a two-way, low-level

bridge at Teal si te .13 The formalconcur rence of the Command-ing General, I Corps, to thisplan was obta ined in lat e Sep-tember, and construction atTea l bega n a lm os t imme -diately.14

The resu lt of the r esearch

progra m, which combined 36year s of J apa nese an d Korean

Figure 19. X-Ray site in Octo-

ber 1952 showing newly erected

ponton bridge and perpendicu-

lar volcan ic rock ba nk s.

observation with two years of Amer ican experience, was a firm convict ion in t he minds of allconcerned that it would be useless to replace the washed-outbridges with ordina ry st ructu res. It was decided tha t only a high-level bridge rest ing on concret e piers extending down t o or se-curely anchored in bedrock would have any potent ial of withstan-ding the extreme flood conditions of the Imjin River and providing

a year -round crossing. It was fur th er believed that th ere was anurgent militar y requirement for such a bridge at X-Ray site in thecenter of the I Corps sector, whether the current tactical situationcont inued, UN. forces advanced, or an ar mist ice was signed. Inthe case of either an advance or an armistice, the Freedom Gatebridge (Munsan -n i ) would pr obably have to be limited t o ra iltr affic, and thus it would become imperat ive to have a highwaycrossing between Munsan -n i an d Kaesong.

Such a justificat ion did not appear to exist a t Teal site; in fact,

it was believed t ha t although an ur gent military requirementexisted for a crossing a t Teal as long as th e cur ren t situat ioncont inued, eith er an advance or an ar mistice would remove therequirement for any crossing at all at t his site. For t hese reasons

-




it was decided th at an expensive high-level bridge could not be just ified at Teal site. The alt ernat ive adopted was a low-levelhighway bridge which would be a vailable for use except dur ingper iods of extreme floods and was designed to permit use withminimum delay after t he flood wat ers r eceded. Thu s, a bridgewhich was expected to be available for use perhaps 5 0 weeks out of th e year was t o be built for less than ha lf th e cost , constructiont ime, and engineer effor t t hat would be required for t he X-Raybridge. l5

The bridges designed for these sites created problems of con-struction which Army Engineers had not experienced before in anactive theater. Teal bridge, for instance, was designed to duplicat ethe relat ively inexpensive “low wat er” bridges so numerous in thesouthwestern United States. These bridges are sturdy enough towithstand being overtopped by flash floods and yet can be pu tback int o service as soon as the water s recede. In order t o dupli-cate t his st rength of constr uction, Teal was designed t o be sup-

ported on piers composed of 164nch, hollow, open-end steel piles,dr iven to bedrock and filled with concrete. This 16.inch Armco

piling was available in the theater but had not been used for t hispurpose before. Other low-level bridges had been built in Korea,but n one ha d been built with t he perman ent-type materials andstrength of the proposed Teal.

X-Ray bridge, on the other ha nd, was a complete depar tu refrom military bridge constr uction. The Corps of En gineers h asdesigned and supervised the const ru ction of lar ger, wider, andhigher br idges, but in most cases these br idges were actually

built by civilian cont ractors or by skilled civilian labor underEngineer supervision. This was the first time t ha t an all-new-construction bridge was to be built with sheet -pile cofferda ms andreinforced concrete piers by tr oop labor . It was to be, in fact , acommercial ra th er tha n military type of bridge, which a ny stat ewould be proud to ha ve as part of its h ighway system.

Both bridges were to be built with in easy range of the enemy’slight ar tillery. As it tu rned out , although enemy art illery rounds

fell near both bridge sites dur ing cons tr uction, t her e was n oindicat ion tha t t he enemy made a delibera te a tt empt to interferewith t he bu ilding of the bridges?



CHAPTER II

The Const ruct ion of Teal Bridge

When the 2d Engineer Construction Group received thedirec-t ive to go ahea d with const ruction of Teal br idge, the job wasassigned to th e 84th En gineer Const ru ction Bat ta lion, a unitwhich has come t o be known a s “The Conquerors of the Imjin.”Lieutena nt Colonel J ames R. O’Grady, commanding officer of thebat ta lion, appointed Capt ain A[rlton] W. Hard in , his Assista ntS-3, as project officer and designated Company B, commanded byCapta in Edward H. Goldsmith , to do th e const ru ction.

Pile penetration tests were made with open-end Armco piles,point ed Armco piles, and 12-inch I-beams. Using a 5,000-pound

ha mmer with 160 blows per minut e, it was possible to drive theI-beam s to a depth of a lit tle over 1 8 feet, the pointed piles to adepth of 22 feet, and the open-end piles to a depth of 27 feet and t obedrock. An a t tempt was made t o pull up an open-end pile withtwo D-8 hyster winches in order to inspect it for split ting or otherdam ages, but it was impossible to extr act it.

The first preparatory work was begun on 2 October 1952 whenCompa ny B began const ruction of a causeway from t he south

shore out to the site of pier 11. The piers were numbered 1 to 16from south t o north. On 10 October the excavation of the approachon t he nort h shore was begun . When the approximate gra de levelof th e appr oach road was r eached, two spr ings which pu t outwater a t t he rat e of about 350 gallons per minute were uncovered.To correct th is situat ion it was necessary t o excava te six feetbelow the grade level, dig a V-sha ped trench with the apex of the“V” at th e springs and the points at eith er side of th e abutment ,and fill i t wi .t h rock t o make a French drain toBy the time the north approach was finished

carry, some

off t he wa te r .14 ,800 cubic

yards of earth had been excavated; some of this earth was pushedout to make the causeway on t he nort h side of the river and latercaused some difficu lty in th e use of hea vy equipment when itbecame boggy. ’
























keep an ar c. Night time, with the necessity for working in as muchblackout as possible and t he usua l decrease in temperat ur e, ag-gravated these difficulties. To meet th is situat ion, canvas shelterswere designed which could be set up ar ound the piers to provide

both shelter from the cold and wind and blackout at night . Theframes of these shelters were so constructed that they could beta ken down an d moved as required.7 (Figure 23)

On 20 November t he welding on pier 11 was completed, andconcrete was poured into the piles. (Figures24 u n d 2 5 ) The canvasshelters were put to a new use at th is time, as it was necessary toprovide heat to keep the concrete in the piles from freezing beforeit cur ed. (Figure 26) A shelter was set up a round the pier, and a

hot-air blower m aint ained a su itable tempera tu re, about 60°,un til the concrete was cured.8

On 29 November, when the tops of the piles were sealed withasphalt and the bearing plates set in place, the first girders werelifted int o place in span 11 with cra nes. The I-beams used a sgirders were of three different types: ten spans were made up of four 36-inch, rolled-steel I-beams; six spans were of four 36-inch,built -up (bolted splices) steel I-beams; an d th e remaining span,

from pier 16 to th e nort h abutment , was made up of six 24-inch,rolled-st eel beam s. (Figures 27,28, u n d 29) The first two typeswere sa lvaged from t he old Teal br idge.

In normal bridge constr uction, to allow for expansion, spa nsar e fixed at one end and r est free on bear ing plates a t t he oth erend with a small guide welded ont o the bear ing plat e to preventsideward movement of the span. This is not true in the case of Tealbridge, which will have to resist the force of the Imjin’s floods.

Both ends of each span ar e bolted in place; however, at one end of the span t he holes for t he anchor bolts are round, and at t he otherend the holes a re slott ed and will allow the span to expand length-wise.g

As soon as the s teel was in place from pier 11 t o pier 9, th ecauseway was cut between th em to allow passa ge of water, andth e causeway from th e nort h shore was pushed out to pier 11.(Figure 30) It was t hen possible to drive the piles for the last four

piers (12 th rough 16). Penetr at ion, t o bedrock on a ll piles, variedfrom 15 feet to 32 feet , 8 inches; average penetration was around27 feet-lo

It was plan ned t o excava te a ll th e way to bedrock for th eabutments so that concrete could be poured directly on bedrock,




but seepage of water into the excavat ion made this impracticable.A key to bedrock was achieved by dr iving four 12-inch H-beampiles to bedrock in th e excavation, capping these with an oth erH-beam, and pouring the concrete abutment around these cappedpi1es.n

On 11 December the two-by-six-inch lamin at ed wood sub-decking was star ted at pier 11 and worked to the south shore; on22 December the diagonal three-by-twelve-inch decking wassta rt ed and nailed down to th e sub-decking at a 45’ angle to thecenter line. (See Figure 29.) The decking had an overa ll width of 22 feet, which, with s ix-inch curbing on either side, left a 21-footrun ning surface for vehicles.

By 10 J anua ry, the decking, cur bing, and guardr ail were inplace on all of th e bridge except span nu mber one, which ha d toawait the completion of th e sout h abu tm ent . The gua rdr ail onTeal consisted of half-inch wire rope str ung through pipe post swhich were set in socket s bolted t o the outside of th e curbing.12

(Figure 32) The guar drail was so designed t ha t it could be re-moved quickly before floods topped the bridge, thereby allowingfreer flow of wat er a nd debris over t he br idge.

All const ruct ion work on t he bridge was completed by 27J an ua ry, an d it was pressed into service prior t o th e officialopening, becau se the division occupying th at sector of the frontwas being relieved and the br idge was needed.13 (Figure 33) Th eofficial opening and dedica t ion of Teal br idge took place on 31J an uar y 1953, when Ma jor Genera l M. M. A-R-West , Com-mander of the Commonwealth Division, cut th e engineer ta pe atth e sout h end of th e bridge.

Teal got its first bapt ism and tr ial in the flash flood of 15 and16 July 1953. The water covered the bridge dur ing the ear ly hoursof 15 J uly, and a t the crest of the flood Teal was un der 12 feet of ru nn ing water . The guar dra il was not removed as planned be-cause of the speed of the river’s rise and the danger of working onthe wet structure, which might be overtopped at any moment inthe darkness. The flood receded on 16 July, and by 3 PM Teal wasfree of water a nd in service again; the only dama ge was to theremovable guardra i l .14 (Figures 34-37)



CHAPTE R III

Const ruct ion of X-Ray (Libby) Br idge

Late in October 1952, the commanding officer of the 84th

En gineer Const ru ction Ba tt alion was advised by the 2d En gineer

Const ru ction Group that his bat ta lion was t o const ru ct t he high-

level bridge at th e X-Ray sit e. “The Conqu erors of the Imjin” were

scheduled for another bout with their old foe. This time the plancalled for the r iver t o be completely overcome before t he next flood

season began on 1 July 1953.

On 1 November work began on dr iving test piles and develop-

ing fuller inform at ion on the overbu rden a nd bedr ock conditions .

Plan s for t he br idge were received on 9 N ovember , and t he ba tt al-

ion began to see the t ype of ta sk it ha d been assigned.l It was to

build, in seven m ont hs, a bridge tha t was completely out side its

experience, a br idge th at would pr obably have required a civiliancons tr uction firm a year t o build in th e sta tes. It could n ot wa it forwarm spring weather and ideal working conditions; the bridge

was needed at once. During most of the next seven months the

battalion would be working in the sub-zero cold of the extreme

Korea n wint er.

The en listed men of the ba t talion cam e from a ll walks of life,

an d m ost ha d n o experience in cons tr uction work . However, every

opera tion on t he bridge was broken down in to the simplest ta skspossible, and th e men lear ned r apidly what was r equired of th em.

Simplified form s, jigs, an d inst ru ctions ena bled them to tu rn out

workmanlike results with a minimum of formal instruction.

Some Korea n civilian s were employed on the job: approxima tely

twenty welders, four divers, two riveters, and others as carpen-

ters, sign-painters, t ire-repairmen, etc. The Korean welders

needed some a dditiona l tr aining, par ticular ly in overh ead weld-

ing, before they could be used; however, roughly 50 percent of the

welding was done by U.S. soldiers. The bat ta lion also had a pprox-

imately 155 KATUSA [Korean Augmentation to the U.S. Army]

personnel, who proved to be excellent construction worke r s . 2

At th e time th e work on X-Ray began, th e batt alion wa s minu s



5 0 B R I D G I NG T H E I M J I N

Company B, which was building the new Teal bridge; Compa nyA, which was const ruct ing tr oop facilities in t he Seoul-Inch’onar ea; and Company C, which was replacing a weakened span of the F reedom Gate bridge. As these compa nies completed t heirprojects, they joined the battalion’s work on X-Ray. Company Bdid not a rr ive un til 1 Februar y 1953.

Preparatory work proceeded through November and most of December-assembling equipment an d supplies and erecting anequipment maint enance shop, a car penter shop, a mater ial stor-age building, and an open storage yard. Causeways were pushedout into the r iver from the east shore past the site of pier 3, andfrom th e west shore beyond pier 6. A sour ce of aggregat e (sa nd an dgravel to be used in concrete) near th e site was t ried an d foundun suit able due to an excess of silt. Another sour ce was foun dupst ream near Teal th at offered clean washed gra vel and sand,an d st ockpiling of aggregate at the X-Bay site began .

The basic plan was t o const ruct piers 6,7, and 8 and the westabutment , using a cent ra l concrete batch plan t locat ed on t hewest bank of the river. Actual construction began on 26 Decemberwith the driving of the first pile for pier 6. Pile driving continued

through piers 7 and 8 on t he west side and piers 1,2,3,4, and 5 onthe east side, in th at order.3 (Figure 39) The great est difficulty inthe construction of X-Bay bridge was with these pier bases: driv-ing the pile, excavating the cofferda ms, and placing the concrete.Ea ch of th e eight caissons pr esent ed a separ at e an d distinctproblem requiring its own solut ion.

The pier bases were constructed by driving grooved sheet pilesto form a recta ngular caisson which was then excavated t o bed-

rock a nd filled with concrete. (Figures 40 u n d 41) The toleranceallowed in rolling th e sheet piling in J apan was too great ; in somecases it var ied a s mu ch as th ree-quar ters of an inch in width .Some of the piles were painted with red lead and some were not.The tolerance was less on t he pa inted piles, and most of the splitsin t he piling were found a t junctu res of the two types. Also thecorn er piles had ball-an d-socket joint s, while the side piles hadthum b-and-finger joint s; this again made it very difficult to fit

properly. The t oleran ce in the grooves cau sed leaks a ll up anddown the joint . Lead wool was used to pack the joints, but this didnot st op the wat er. Event ually soft wooden wedges, dr iven intothe joint s, proved to be a fair ly effect ive mea ns of stopping th eflow.4




The poor quality of the sheet piling greatly increased the

difficulties of dewatering the cofferdams to permit excavation

down t o bedrock. In a ddition, th e rough, irr egular su rfaces of the

bedrock m ade it almost impossible t o get a tight seal between pile

and rock. Blowout s under t he p iles inevita bly occur red before t hefina l clean -up could be completed. Fr equen t ly the sheet piles split

near the bottom, with the result that backfill (filling up the

excavat ion), pile extraction, an d redrive were necessar y, as man y

as three times for one of the cofferdams. Unfortunately, when

cofferda m 6 was excava ted, th e pile extr actor ha d n ot ar rived yet,

an d it wa s necessar y to mak e th e initial concrete pour completely

un der wa ter . On t he oth er cofferda ms, a s excavat ion proceeded, it

was possible t o remove boulders th at obstructed full pile penetr a-tion, extr act and r eplace bent piles, and t hen drive the piles all the

way to bedrock. In excavat ing cofferdam 1, it was foun d tha t t he

piles a t one corn er h ad str uck a layer of basa lt; however, it was

possible to backfill, extr act t he ben t p iles, replace them, an d dr ive

on down to bedrock .5

Sub-zero weather greatly handicapped the operation of the

dewater ing pumps, which r equired const an t supervision. During

operat ion , ice would form on th e ou tlet s a nd conn ect ions , pluggingup the pumps. When a pump was not in operation, water would

freeze inside the pump mecha nism. It was n ecessary to apply hea t

externally to these points to get the pumps operating and to

repeat the application of heat frequently to keep them going.

It was foun d to be a general rule that th e more water t ha t was

pumped out of a cofferdam , th e more likely a blowout was to occur

under the pile. This was due to the decreasing inside p r e s s u r e . 6

(Figure 42) In t he lat er st ages of the cofferdam work , divers wereused to great advantage to overcome this. The cofferdam was

allowed to fill with water when the bulk of the excavation had

been accomplished, and divers were used t o clean th e bott om of all

sand , gra vel, an d loose bedrock. Following th is, an initia l pour of

th ree t o four feet of concret e was made, keying th e pier t o bedrock

and sealing off the bottom of the cofferdam. The cofferdam could

th en be dewat ered a nd work cont inued “in t he dr y.” Only coffer-

dam 8 was poured completely in the dry.In these excavations to bedrock, Major William C. Carter,

bat ta lion S-3 and project officer, found evidence to refut e, at least

partially, the theory advanced in the preparatory studies for the

bridge that the overburden (mud, sand, gravel, and other ma t e -




r ial covering bedrock in the bed of the r iver) a long most of thelength of the Imjin is moved completely by the scouring action of the river during flood season. The a ppearance (corrosion of rocks,etc.) of samples of the overburden procured in the excavation of

the cofferdams led Major Carter to conclude that the lower over-burden a t X-Ray had not been moved by scour ing for many years.The bedrock itself did not appear to him t o ha ve been eroded byscour action for several hu ndred years.7 If th is is th e case, Libbybr idge will have an even grea ter possibility of su rviving th efloods due to the additional protection afforded the caissons by theoverburden.

Fr om the beginn ing of the pr oject in November u nt il lat e in

April, work was car ried on thr ough periods of extreme cold, sleet,and snow storms; very few times was the work st opped, day ornight , on accoun t of the weather . Flash floods and spr ing hightides eroded the causeways and on 20 March an d 13 May 1953went completely over them. The water and the need for immedi-at e repair of the cau seways made the evacua tion of men a ndequipment necessary on several occasions!

Motors became practically impossible to start without the use

of special warming devices, and it was fina lly decided to keep themotors of key vehicles and equipment ru nn ing 24 hours a day.Condensat ion of water in t he pneumatic hoses would freeze at theconnections and plug the hose; th is could only be solved by apply-ing constan t hea t to all such connect ions. The same difficulty of welding in t he extr eme cold which was experienced at Teal waspresent at X-Ray.

Mixing, pour ing, and curing concrete in freezing weat her,often below zero Fahr enh eit, presen ted a whole new series of problems t o Major Cart er and t o Fir st Lieutenan t Dona ld W.McKenzie, comm ander of Company A, who was in cha rge of a llconcrete opera tions . An aggregate dryer, capa ble of handling 50to 180 tons per hour , was u sed to heat the aggregate t o an accept-able temperatur e, and a 24.head shower unit, permitt ing tem-perature control from 37O to HOOF , heat ed the water for mixing.(Figures 43 CVZ~ 44) Once the concret e was poured, it would soonlose its heat and freeze unless some means was found to maint ain

a const ant above-freezing temperat ure until it was cured. Uniquecur ing cabins covered with canvas were designed which servedth e double purpose of ma intaining heat an d providing a work platform. These cabins could be raised and clamped in place as the




pier rose, and they also served as overhead support for the pipewhich would deliver concrete in the later pours. The temperatureinside the cabins was maint ained at 60’by Herma n Nelson hot-

air blowers; in addition, spra y bar s were used t o keep the cur ing

concrete moist with warm water.gIn ear ly Februa ry 1953, the first pour ing of concret e--in cof-

ferdam 6, which wa s full of wat er-was accomplished with con-crete buckets a nd a cra ne. This pr ocedure proved t oo slow an dcrea ted a great deal of wash an d wave action, which t ended towash the cement out of the mix. After about 20 buckets of concretewere placed, placement was st opped an d a new mea ns wasadopted. A 16Gnch Armco pile with a hopper a t tached was used as

a t r emie to car ry t he concrete down t o the bot tom of th e cofferda m ;th e lower en d of th e pipe was k ept a bout one foot below th e su rfaceof the concrete already poured in order to prevent washing of themix. The r emainder of pier 6 was placed in t h is manne r l o

There were still doubts as to the qua lity of th e concrete in pier6, and fur ther pour ing on this pier was ha lted until tests could bemade. An a tt empt was made to obtain samples of the concrete bY

coring, but this did not pr ove Successful as only about two inches

of core were ever obta ined. 0 n 4 Ma r c h>n order to blast out theconcret e cam e down from t he Eighth Army En gineer . The pierwas blast ed out down to bedrock, and the concrete, except for thethree and four feet at the bottom, was found to be unsatisfactory.On 16 March t he pier was r epoured using a pumpcrete machinewhich produced better results? (F igure 45)

Excavation of cofferdam 8 was completed on 13 February, andth e concrete placement was begun using concrete buckets an dcranes. This was the only pier pour ed completely in the dry. With

the oth er piers it was n ecessar y to place a t h ree - or four -footblanket of concrete at the bottom t o reduce wat er leakage and t hedanger of a blowout , then dewater and drill through the concreteto bedrock t o test it, before placing th e rest of the concrete.

By late Februar y a pumpcrete machine had ar rived and wasoperat ing; th is unusual device:was capable of pumping wet con-crete for long dista nces and to considerable height s. The timerequired for concrete pouring was greatly reduced due to the

speed with which the pumpcrete could deliver concrete to the spotwhere it was n eeded.

Five pour s or l i fts wer e m ad e on ea ch pier, and th ey were given-alphabet ical t itles for ease of reference. “A” pour was an average




of 240 cubic yards of concret e in the caisson; “B” pour was the twolower 165foot vert ical columns, the lower par t of the H-shapedpier. “C” pour was t he horizont al middle stiffener , and “D” pourwas the two upper vertical columns above the stiffener. “E” pour

formed the cap across the top of the “H”. After it was in operation,all pour s were ma de with t he pumpcrete. (P’igures 46 a& 47) Tocomplete pier 5, for instance, concrete was pumped 700 feet hori-zonta lly an d 48 feet vertically.12

Wherever possible, components of the bridge were completedan d assembled on the sh ore before being placed on th e bridge.Reinforcing steel was prefabricated into mats of the required sizein th e cent ra l work yard a nd h au led to the point of use when

needed. (Figure 48) All forms were made in t he car pent er shopunder the supervision of Second Lieutenant Harry H.Nishikimoto and, whenever possible, were so designed t ha t th eycould be taken down and reused. A cur b form was designed t ha twould use t he same bra cket t ha t held the deck slab form . Thesuperstructure operation was geared to placing 242 feet of deck aday, and the curb placement was similar ly geared, using the sameforms. Guardrail posts were cast in ba tches of 66, using the same

forms over and over .13 (Figure 49) A full-scale model of a sect ion of the deck was built in t he work yar d to give to a ll concern edpractice and t ra ining in the procedures which were to be used.(Figure 50)

Steel fabr icat ion and placement ra ised ma ny problems. TheJapanese-manufactured 4%inch I-beam s, which were to be usedas girders, had to be riveted together with splice plates in order toform girder spa ns of th e required length . Fa bricat ion began in

Februar y an d cont inued th rough 5 J une with First LieutenantCurt is W. Badman , assisted by War ran t Officer Harry Cooley, inovera ll charge of all st eel const ruct ion.

On th e day riveting began, the only man in th e batt alion whohad civilian experience as a riveter departed for home. However, aweek’s schooling and the help of two Korean riveters soon turnedout good crews. The rivet hammers available th rough Army sup-ply channels were too light for the seven-eighths-inch r ivets used,an d suita ble ham mers had t o be ren ted from a Korean contrac-t o r . 14 (Figures 51 and 52)

In ea r ly April the beams which were to span from t he westabutment to pier 7 were completed. The two downstream beamswere then spaced at the required distance apar t and braced dia-






























phragmed) with six-by-six-inch angle iron and fifteen-inch chan-

nel iron between beams to form a pair of girders as a unit for

launching. This downstream pair was then launched with a 30-

foot launching nose fixed to the front at an upward angle to

compensate for any downward deflection of the beam when itreached the pier, and a coun terweight was a dded to the t ail of th e

girder to prevent tipping. (Figure 531

Since the girder had to be launched horizontally across the

abu tm ent , which was a t deck level, hea vy wooden cribbing h ad to

be placed on t he pier caps to receive an d support th e beam s un til

they could be jacked down into position on the piers. The three

upstream beams were launched complete with the corrugated

steel sub-decking already welded in place. This sub-decking,which was available in Korea, provided a simple and speedy

mea ns for const ru ction of th e deck form s and did not h ave to be

removed when the concrete deck was completed. The girders to

span piers 1,2,3,4, and 5 an d th e east abut ment were fabricat ed

on the east shore and launched across the east abutment. Less\cribbing and jacking down were necessary for these girders be-

cau se th e top five feet of th e end wa ll of th e abu tm ent ha d n ot yet

been pour ed, and th e girder s could be lau nched just slightly above

th e elevation a t wh ich t hey were to rest . These girders were 606

feet long when launched, and moving them out to their position

required a great deal of engineering skill?

Lieutenant B a dm a n an d War ran t Officer Cooley cam e up with

a s uggestion th at ma de it possible to weld th e sub-decking on a ll

girders before they were launched, thus saving a great deal of

time an d effort after t hey were lau nched. The plan was t o launch

the downstream girder (two of the five I-beams connected with

diaphr agming) five inches higher th an th e upstr eam girder (th eother three beams); this would allow the decking of the down-

stream girder to pass the decking of the upstream girder freely

dur ing lau nching, without scra ping. Then when th e two girders

were lowered in to position , the decking would tight ly fit t ogeth er

a s p l a n n e d ?

The spa n for piers 7,6, and 5 was fabr icat ed on t he west sh ore

an d lau nched over t he completed decking of piers 7 a nd 8 and the

west abutment. (Figure 54) Another time-saving expedient wasused h ere in lowering th e girder s int o position; a fram e with cha in

hoists was a nchored t o th e completed decking of th e oth er spa ns

an d lowered th e downst rea m girder in 22 hour s, while with jacks




it r equired eight days to lower the corr esponding girder of piers 7and 8 and th e west a butment. (Figures 55 an d 56)

Superstructure operations had been proceeding rapidlywher-ever the girder s were in place, but when t he last girder s were

finally in place the decking opera tions went into high gear as theta rget dat e for completion drew near . The reinforcing steel matswere laid, and the concrete decking was placed with a discha rgechute at the end of the pumpcrete pipe; a st ra ightedge was used toobtain the desired plane, followed by a burlap drag to remove anyexcess moistu re a nd to give the desired rough sur face textur eperpendicular to the flow of traffic. (Figures 57 and 58 ) Theconcrete was poured on 14 J une, and seven more days of cur ing

with water -soaked bur lap were then r equired. (Figure 59) Clean-up operations, which consisted of scraping down all piers, paint-ing the guardrails, removing all scaffolding and catwalks, sweep-ing down t he deck and cur b, pa int ing th e bot tom flan ges of allbeams, and dressing down t he a pproaches, cont inued for sometime afterward.

An interesting feature of the bridge’s construction, which wasra ther painful for all concerned, was the preparat ion for demoli-t ion should it become necessary. YRvo steel cat walks ar e sus-pended crosswise under t he br idge between piers 6 and 7 withsteel ladders leading down to them on both sides. Inst ru ctions asto the amoun t an d placement of explosives ar e paint ed on th esides of the beams. The plan of demolition calls for cutting each of the five beams between piers 6 and 7, allowing th is sect ion of thebridge to drop int o th e river, which h as its main cha nnel at th ispoint . Channel-iron brackets ar e welded to each beam to hold theexplosive in place, and a yellow str ipe is painted across the deck at

each end of the span to show the proper placement of cha rges tobreak the concrete decking. l7

The origina l ta rget dat e for complet ion of the bridge was 1

J uly 1953. It was finished on time, but only because of a great dealof prior planning, hard work, and aggressive spirit on the part of all concerned to get t he job done. F’rom November through March,work proceeded on two ten-hour shifts; later in March, twoeleven-hour shifts were put into effect; and after 1 June, two twelve-hour

shifts were employed unt il the complet ion of the bridge.F’reezing weather , high winds, floods, high t ides, and even

some enemy artillery, all cont r ibuted to slowing down construc-

tion. In the const ru ction itself, the dr iving, excavat ing, and pour-




ing of the caissons caused the most delay. Becau se of these diffr-

culties most of the completion dates for the phases of constructionwere not met. As Major Carter r emarked, “We didn’t do anyth ingon time except finish.“18

%o men were killed dur ing the construction of the br idge.KATUSA Corpora l Kim Ho Duk was killed on 31 J an ua ry 1953when a boom failed on a three-quarter-yard Buckeye clam on pier7. Pr ivate J ames E. O’Grady drowned on 16 April 1953 trying tohelp a Korean civilian worker who had become cau ght in ropesan d was in da nger of drowning when t he boat in which h e wasworking capsized. The commanding officer of the 84th recom-mended that the bridge be named for these personnel. However,

the Commanding General, Eighth Army, directed tha t t he bridgebe na med for Sergean t ‘George D. Libby, 3d En gineer Comba tBattalion, who was posthumously awarded the Medal of Honor forgallan t conduct and heroic self-sacr ifice at Taejon, Korea, on 20

July 1950.1g (F igure 63) The Libby bridge was dedica ted withappr opr iate ceremonies on 4 J uly 1953 by Genera l Maxwell D.Taylor, Comm an ding General, Eight h Arm y, an d was imme-diat ely put in to service.



Appendix A

CORRESPONDENCE BETWEEN I CO R P S A N D E I G H T H A R M Y

L E A D I N G T O THE APPROVAL OF THE CONSTRUCTION

OF T EAL B R I D G E

HEADQUARTERS I CORPS

OFFICE OF THE CHIEF OF STAFFAPO 358 U.S. ARMY

AG 823 CICS 2 August 1952

SUBJECT: Imjin River Br idges

TO.

. Comma nding Genera lEighth United Sta tes Arm y Korea (EUSAK)APO 301

1. Recent floods in this sector have dest royed two of the fivefixed bridges over t he Imjin River which were available to the ICorps.

2. Whereas t he Corps can an d will be support ed over th eremaining bridges dur ing the rema inder of the flood season thisyear , it is considered t ha t the replacement of the da maged X-Rayan d Teal bridges is an ur gent milita ry necessity. It is fur th erfirmly believed th at more su bstant ial types [ofl stru ctur es ar eindicat ed rat her than restorat ion of those str uctu res which h aveproven inadequat e in t he face of th e high water .

3. It is deemed import an t th at ear ly considerat ion of th is




matter be given with the specific object of providing replacementbridges at the earliest.

FOR THE COMMANDING GENERAL:

s/J ohn K. Wat erst/JOHN K. WATERS

Brig Gen GSChief of Staff



APPENDIX A 73

AG 823 KEN-C 1st Ind(2 Aug 52)SUBJ ECT: Imjin River Br idges

HQ, Eight h U .S. Army Korea (EUSAK), APO 301, 11 Aug 52

TO: Comm anding General, I Corps, APO 358

1. Replacement of dama ged Imjin River br idges will be ac-complished when present river conditions warrant and potentialflood thr eat has termina ted.

2. At t he present t ime an extensive study an d resear ch pro-gram is being conducted to provide basis for design and constru c-tion of type st ructu res capable of withstan ding stage floods andabnormal r iver conditions encountered on the Imjin and its t r ibu-tar y streams.

BY THE COMMAND OF GENERAL VAN FLEET:



To .. Commanding GeneralEighth United Sta tes Army Korea (EUSAK)AP O 301, U.S. Arm y

1

da tedReference: Letter this Headquarters, subject as above,2 August 1952, and 1st indorsement thereto.

2 . To provide adequ at e support for elemen ts n ort h of th e ImjinRiver, t he perm an ent bridge destroyed X-Ray site (CT 095012)an d Teal s i te (CT 174056) dur ing the f lood season jus t t e rm inat -ing ar e being t emporar ily replaced with float ing M-2 t r e adway

bridges by Corps engineers.


HEADQUARTERS I CORPSOFFICE OF THE CHIEF OF STAFFAPO 358 U.S. ARMY

14 Septem ber 1952

SUBJECT: Imjin River Bridges

3. Previous experience has demonstrated that floatingbridges cannot be indefinitely maintained across t he Imjin Riverduring the winter months when ice conditions prevail. To preventun necessar y loss of equipment , it is cons idered desira ble to r e-

move all float ing bridges about 11 December 1952, the mean da teof freeze-up on t he Imjin. To provide for cont inu ed sa t isfactory

support of the forwar d elements in t he I Corps zone of act ion, itwould seem h ighly desira ble th at permanent stru ctu res at th eTeal and X-Ray bridge sites be completed pr ior t o dama ging iceconditions .

4. In order tha t t his Headquart ers may cont inue its plann ingfor winter operations, it is requested that information relative to



APPENDIX A 75

perma nent str uctu res at X-Ray and Teal sites be fur nished at t he

earliest pra ctical da te.

FOR THE COMMANDING GENERAL:

s/John K. Waters

t/JOHN K. WATERS

Brig Gen GS

Chief of Staff



76

KEN-C

BRIDGING THE IMJIN

Imjin River Br idges 24 Sep 52

Engr

G-3 Concur __--Y-___- Nonconcur -

G-4 Concur -________ Nonconcur --______

AG For signa tu re and dispat ch

1. Sta tement of th e problem: To submit a plan t o the Corn-mand i ng General, I Corps, for replacing Imjin River br idges.

2. Fa cts bear ing on t he problem:a. Equa lly spaced along t he Im jin River ser ving t he 1st

Marine Division, th e British Commonwealth Division, and the 3dU.S. Infant ry sectors were, prior to 1952 flood sea son, five high-level bridges. wo of those (Parker and Whitefront) with stood thefloods. One (Munsann i ) , poten tially the best an d most critical,ha s one tempora ry pier which was severely th rea tened. %o (X-

Ray and Teal) were washed out leaving a large gap in the lines of commun icat ion over t he r iver. (Tab A)b. I Corps considers the replacemen t of the two br idges

washed out with more substantial structu res as ur gent militarynecessity. (Tab B)

c. I Corps desires to be informed of the EUSAK plan for thereplacement of those br idges. (Tab C )

d. A general plan has been appr oved for replacing the t empo-rar y span in th e Mun s a n n i railroad br idge. (Tab D)*

3. Discussion:a . For these sites two general designs appear feasible. One is

a two-way high-level bridge cost ing approximat ely $600,000 an drequir ing eight (8) months to build. The other is a t wo-way low-

level bridge at about two-th irds t he cost and one-ha lf th e t ime.The low-level bridge will be topped during floods. It is est imatedtha t such a br idge would be impa ssable not m ore t ha n t wo or

th ree months dur ing the year.b. The sit es of the old five high-level bridges a re evenly

spaced along th e river a nd a dequa tely serve th e near an d farshore road nets. From an Engineer point of view they are excellent



APPENDIX A 77

permanent bridge sites. There ar e numerous float ing bridge sitesalong the r iver which can be used dur ing the intervals betweenthe flood season, 1 J uly to 15 September , and t he ice season, 15

December to 25 March, only. Pr evious exper ience has indicat edconclusively that float ing bridges can not be ma int ained acrossthe Imjin du r ing these periods especially in the lower reacheswhere t he r iver is a ffected by the tide.

c. A plan was discussed with En gineer of I Corps to replacethe X-Ray br idge with the two-way high-level bridge to be com-pleted before the 1953 flood season and to replace the Teal bridgewith the limit ed two-way low-level bridge. This plan ha s beeninforma lly concurred in by th e Chief of Sta ff, I Corps.

d. The h igh-level bridge at X-Ray appear s just ified on thebasis tha t in addition to the I Corps r equirement for a permanentbridge for th e present situa tion t here will be an all-year -ar oundrequiremen t including the flood season for such a bridge bothafter a possible armistice or an advance in tha t sector. After anar mistice or a n advance th e Munsan -n i ra ilroad bridge wouldprobably ha ve to be limited to rail tra ffic an d th us a h ighwaycrossing is r equired between Munsan-n i an d Kaesong.

e. Su ch a just ificat ion does not a ppear to exist a t Teal . In fact ,

it would appear that , in any situat ion except for a cont inua tion of the present one, the r equirements for any crossing at all at Tealwould cease to exist.

4. Conclusion: .

a. Tha t th e plan inform ally presented t o I Corps is feasibleand just ified.

b. Tha t form al concur rence of the Comm an ding Genera l, I

Corps, is required.

5. Recommenda tions: Concurrence an d dispa tch of at tachedlett er. (Tab E)*- LT COL HIMES1_--_ COL DOVVNING2___._ COL BAKER3

Sch Adv 315 Sch Adv 615 Sch Adv 615

*Not a vailable for inclusion




HEADQUARTERS

EIGHTH UNITED STATES ARMY KOREA (EUSAK)

APO 301

AG 823 KEN-C 29 September 1952

SUBJECT: Repair of Imjin River Bridges

To .. Comma nding GeneralI corpsAPO 358

1. Reference lett er your headquar ter s, dated 14 September1952, subject : “Imjin River Br idges.”

2. Past experience and r esults of studies of th is headquart ershave conclusively indicated that the only bridges which will havean y poten tia l for with stan ding ext reme flood condit ions in t heImjin River are bridges resting on concrete piers extending down

to or secur ely anchored in bed rock. Such st ru ctu res a re ex-tremely expensive and will require both extensive engineer effortan d time-consuming constr uction.

3. It is believed tha t t here is an urgent militar y requirementfor a safe, all-weather, all-year-ar ound railroad crossing at M u n g

sanni an d a similar highway crossing in t he Mun san ni-X-Rayreach of th e Imjin, wheth er t he pr esent ta ctical situat ion con-

tinu es, wheth er our forces advance, or wheth er a n ar misticeensues.

4. To meet these requirements, it is planned tha t t he tempor-ary span in th e Mun s a n n i ra ilroad br idge be replaced imme-diately by a permanent span with a planned completion date priorto 1 J anua ry 1953, and to const ru ct at the X-Ray site a two-wayclass-60 high-level, a ll-weather highway bridge with a plannedcompletion date some t ime between the ice season of 1952-1953and th e 1953 flood sea son.

5. It is believed there is also an ur gent military requirement



APPENDIX A 79

for replacing th e Teal bridge which washed out during the pastflood season. To meet this requirement it is planned to construct alow-level limit ed two-way class-60 highway bridge which will beavailable for use except during periods of extreme floods and

which will be of such design a s will permit use with a minimumdelay after flood wat ers recede. Resen t planning indicat es tha tsuch a bridge can be completed by 1 January1953.

6. Request your comment s and/or concurrence in t he a boveplans.

BY COMMAND OF GENERAL VAN F LEE T:

s/C. W. Burlesont /C. W. BURLESON

Lt Co1 AGCAsst AG



Appendix BE N G I N E E R I N G R E P O R T O N BRIDGE STUIIY AN D D E S I G N, T E A L

S ITE , I MJIN R IVER, 2~ E NGINEER C O N S T R U C T I O N G R O U P ,

14 S E P T E M B E R 1952, W ITH S E L E C T E D A ~ A C H E D D O C U M E N T S

HEADQUARTERS

2D ENGINEER CONSTRUCTION GROUPA P O 9 7 1

Engineering Report on Bridge Study and Design,

Teal Site, Imjin River

CONTENTS

Section I Introduction Page 1Section II The P roblem Page 2

Section III Discussion Page 3

Section IV Conclusions Page 5

Section V Recommendations Page 6

Inclosure

1 Acknowledgment

2 Opera tions Order No. 33, 13 August 1952, Hq,EUSAK

3 * Plott ing of Core Drill Sam ples, Honker Site, ImjinRiver

4 Geological Report on Imjin River, prepared by

FECOM

5* Hydrograph ic Dat a, Imjin River a t Teal Site



APPENDIX B 81

6* Cross Sect ion of Imjin River a t Teal Site, with High-water Levels

7* Proposed High-Level Bridge Data

Design Computat ionsCost EstimateCritical Items of Materials and Equipment

8* Proposed Low-Level, One-Way Bridge DataDesign Computat ionsCost E stimateCritical Items of Materials and Equipment

9* Proposed Low-Level, Two-Way (Restricted Traffic)

Bridge DataDesign Computat ionsCost E stimateCritical Items of Materials and Equipment

10 * Proposed Low-Level, Tbvo-Way (Unrestricted Tkaffk)

Bridge DataDesign Computat ionsCost Estimat eCritical Items of Materials and Equipment

Attachments*

Plan A Drawings for Proposed High-Level Two-WayBridge

Plan B Drawings for Proposed Low-Level One-WayBridgePlan C Drawings for Proposed Low-Level Two-Way

(Restricted Tkaffk) BridgePlan D Drawings for Proposed Low-Level ‘Iwo-Way

(Unrestricted Traffic) Bridge

*Not reproduced




HEADQUARTERS2D ENGINEER CONSTRUCTION GROUP

APO 971

14 September 1952

Engineering Report onBRIDGE STUDY AND DESIGN

At t he Teal Site, Imjin River, Korea

I. INTRODUCTION

1. If the Imjin River is viewed for t he first time during normalweath er condit ions, a pictur e is revealed of a small mount ainstr eam surr ounded by rugged mounta inous t err ain lazily wind-ing itself into the distance. The active channel is relatively smallin comparison to the overall width of the river bed. It can easily beforded in most places. The a lmost vert ical r ock cliff ban ks, ap-proximately 75 feet a bove low water, the wide dry river bed of about 1200 feet width , and t he sha llow act ive chan nel of about150 to 200 feet width indicat e that the Imjin River is approachinga stat e of old age. There is no indicat ion du ring norma l times of the monstrous force tha t the Imjin River actua lly develops dur ingfloods.

2. The Im jin River, fed by its tr ibut ar ies an d ma ny smallmounta in st ream s, reaches flood height s of 48 feet above meanlevel and a velocity of 15 feet per second and discharges nearly six

million gallons of wat er per second. The r apid runoff of appr ox-imately 95% of precipita t ion du r ing flash floods has caused th eImjin River to rise more than six feet per hour. There is no specificinform at ion on what action occur s in t he sa nd and gravel over-burden in the river bed during a flood. However, experience withscour action an d the floating out of piling which had 12 to 15 feetof penetrat ion indicates that the overburden of sand and gravel inth is fast -moving stream is unsta ble to a depth perha ps equa l to

th e depth of th e flood wat er in th e str eam, or to bed rock, whichever is less.

3. In t he prepar at ion of th is repor t, extensive use has been



APPENDIX B 83

ma de of available techn ical da ta , report s, test s, drillings, an dstudies of other Korean r iver projects and studies made by J apa-nese en gineers dur ing th eir 36 year s of occupation of Korea .Advice and assist ance of technically qua lified Korean engineers

who worked with the Japanese engineers during their occupationhas also been utilized (see Inclosure 1 for acknowledgments). Thisinforma tion t ogether with knowledge gained by the U.S. ArmyEngineers dur ing the two year s of U.S. opera t ions in Korea hasbeen used to th e maximum extent possible in prepar ing th e ana l-ysis, designs, and recommenda tions cont ained in th is report .

4. Attached as inclosures and referenced hereunder are

copies of core drilling tests by Japanese engineers, hydrographicdat a obta ined from J apa nese r ecords, and design calculat ionsmade by th is headquart ers, all of which ha ve been u sed in th isbridge design report. The flood conditions, which have not abatedsince 30 J uly 1952, have prevented accomplishment of core dr il-ling at th e Teal site, although cont ra ctors, equipment , and per -sonn el ha ve been available to st ar t t ha t work. Seismographequipment and crews have not been foun d available to ma ke

quick pr ofile studies of the r iver bed subsurface. A sheet-pilingcaisson will be sunk a t the bridge site and soil samples taken foran alysis a s soon as th e flood wat ers recede. Until th is river bedexplorat ion is completed, the soil structure of the r iver bed and it s

bear ing capacity can only be assumed from geological s tudies andfrom int erpreta tion of known dat a a t downstr eam sites, whichsites were st udied by the J apanese engineers. It is believed thatthis interpretation is sufficiently accurate to provide basic designcrit eria a nd to allow const ru ction estimat es with in a bout 15%accuracy.

5. Designs of two different basic types of br idges have beendeveloped for the pu rpose of th is r epor t . A high-level, class-50two-way, permanent type bridge for all-year use is our considera-tion of the only feasible str ucture that will insure un interr uptedyear-around use and be able to with sta nd normal an nu al andexpected floods on the Imjin River. Its design is restricted tomaterials generally available in Korea. Due to the cost in mat e-ria ls and const ru ction effort and length of time required for con-st ru ction of a permanen t br idge, an alternat e type design for alow-level fixed bridge is offered for consideration. The low-level




bridge is considered stable against flood damage but it will not beusable dur ing high floods.

6. Design drawings and const ru ction estimates for the high-

level perma nent bridge and the one-way low-level and t wo-waylow-level bridges ar e at ta ched as separat e plans. It is consideredthat the results of the core drilling (yet to be performed) will notaffect the br idge design, but will only indicat e the depth to whichpiers will have to be sunk.

7. Time has not permit ted the development of deta iled specifi-cat ions an d const ruct ion schedu les for each of the bridge plan s

submitt ed herewith. Prelimina ry estimat es of time and const ruc-t ion effort required for each type of bridge ar e included in thereport. Upon notice by higher headquarters of the design ap-proved for construction, the specifications and construction sched-

ule for t ha t design will be prepar ed and submit ted for a pproval.

II. THE PROBLEM

8. A high-level one-way t imber br idge was const ructed overthe Imjin River at the Teal site (CT 174057) dur ing the wint er of 1951-1952. Tha t site is within t hr ee miles of th e present frontline (MLR). Timber piling and timber bent s were used for all piersexcept the thr ee piers a djacent to the north ban k of th e river,which piers h ad steel H-beam piling. Dur ing the floods of J ulyan d August 1952, th e bridge was lost due to dam age by floodaction. Report of th is headqu ar ter s t o th e En gineer, EUSAK

[Eighth United St at es Arm y, Korea], 20 August 1952, subject :“Preliminary Analysis of Damages to Imjin River Bridges duringthe Flood of 30 J uly 1952,” provides informat ion on damagessuffered to tha t t ime. The flood of 24 August 1952 washed outabout one-ha lf th e stru ctu re th en remaining. The Engineer,Eighth Army, subsequently ordered the rema ining str ucture re-moved an d sa lvaged.

9. In Oper at ions Order No. 33, 13 August 1952 (Incl2), theEn gineer EUSAK directed t his headquar ter s to submit designdata, specificat ions , an d cons truction plan s for a “class-50, two-lane Hi-level Highway Bridge over the Imjin River in t he vicinity



APPENDIX B 85

of the Teal site.” Such br idge is proposed to replace th e originalTeal bridge and is desired t o provide a r iver crossing to be used insupport of combat u nit s locat ed north of the Imjin River in t ha tvicinity. The purpose of this report is to meet the requirements of

Opera t ions Order No. 33.

III. DISCUSSION

10. The report of 20 August 1952, referenced in pa ra graph 8

above, reflects th e opinion of this h eadquar ter s concern ing the

unstable overburden in t he r iver bed above bed rock. It is appreci-at ed that th is opinion cannot be proven unt il the river bed explo-rat ion is completed and the soil is ana lyzed. However , evidencenow available is so str ongly indicat ive of the inst ability of theoverburden in t he river th at it appear s necessary to base thebridge design on that assumption. From an analysis of the Honkerbridge design, it appears that the J apanese engineers appar entlyreached t he same conclusion dur ing the t ime of their occupa tionof Korea . (See report referenced in par agraph 8 above.) The bestqualified Korean engineers (who also worked with t he J apaneseengineers) were recently consulted on this matter and were foundto be firm in t he same conviction. Records of core dr illings a t theHonker site (CS 086968) (Incl3) provided by Korean engineersfrom Japanese records, indicate an average depth of overburdenof about 20 feet.’A geological stu dy furnished by the EngineerFECOM [Far East Comma nd] (Incl 4) indicat es th at th e over-burden may be somewhat less upst ream from the X-Ray site (CT

095013), perha ps about 15 feet in depth. For the pu rpose of thisstu dy and u nt il core dr illings ar e obta ined, an average depth of < .overburden iq assu med as 20 feet.

1#

11. Hydrographic da ta (Incl 5) was obta ined from r ecordscompiled by Japan ese engineers during th eir occupation of Ko-rea. Those records a re now in the files of the Bureau of Pu blicWorks, RQK [Republic of Korea]. This da ta agrees generally with

th e data pr ovided by FECOM in t he report referenced in par a-graph 10 above (Incl 4). A surveyed cross-section of the ImjinRiver channel at th e Teal site, together with high water recordsplot ted th ereon, is included at Incl 6.




12. The h igh-level bridge proposed for considerat ion is de-signed for use of const ruction mater ials and equipment norma llyavailable through supply cha nnels in Korea.. There .may be somenecessary items of materials and equipment in short supply, and

if actua lly found to be not available (and no suitable subst itutes),their shortage may be the deciding factor in selection of the bridgedesign. A listing of these suspected critical it ems is included withthe inclosur e for each separat e type design. There ar e not believedto be any crit ical items requir ed in const ruct ion of the low-levelbr idges proposed for considerat ion, alt hough special supply ac-

tion ma y be necessar y to procur e some of th e ma ter ials an dequipment required.

13. Simplicity of design for ear ly const ruct ion of a br idge inKorea is necessa ry due to lack of const ruct ion skills, lack of special ha ndling equipment , speed of const ruct ion desired, an deconomy in use of const ruction forces and ma ter ials. Severa lalternat e sites were stu died, and several alternat e designs a nd

combinat ions were ma de an d pr elimina ry cost estimat es pre-

pared of each for compar ison. Two bas ic types of br idges ar e

developed in the designs offered for consideration, and all of theother a lternat es considered ha ve been eliminated without inclu-sion in t h is report . The or igina l Teal site (or possibly 50 feetupst ream depending on resu lts of core dr illings) was found to bethe most economical site for const ruct ion of a h igh-level br idge,an d a slight ly fur th er u pstr eam site was foun d to be th e mostfeasible for construction of a low-level bridge.

14. The high-level bridge is a design using four 48” I-beams,cont inu ou s section over t wo spa ns , with 121' 4" span s. The deck-ing is corr uga ted m eta l sheets V32” x 13" x 13' with a 4" concretewear ing su rface. Wood decking is offered as an a lter nate for

.consideration. The piers finally selected, after studies were madeof severa l different designs, are reinforced concrete with a solidbase (tied into bed rock) extending to appr oxima tely mean lowwat er level, with two vert ica l columns (essent ially forming abent) 5 x 4’ at base an d taper ing to 3’x 4’ a t t he cap. Const ruc-

t ion details ar e shown on t he a tt ached drawings, Plan A. Designcompu tat ions, cost est imates, an d a listing of suspected crit icalitems of mater ials and equipment a re included at Incl7. Assum-ing th at work can be sta rt ed on t he h igh-level bridge by 1 October



APPENDIX B 87

1952, an d th at al l necessary supplies and equipment can be ma deavailable without undue delay, the bridge should be completed byJ un e 1953; although a t rem endous work load will be requiredafter the spring th aw. This const ru ction schedule assumes that

concrete work, except the base of the piers , will not be feasibledur ing the wint er from about 15 December 1952 un til 1 Apr il1953. The construction effort will be about eight Battalionmonth s. The est imat ed tota l cost is $1,167,366.00.

15. An a lterna te plan of construction for the same high-levelbridge is under consideration and will be studied in more detail if the high-level bridge is au thorized for const ruct ion. The major

cha nge in design would be constructing skeleton bent s of 24"I-beam s (cross-braced), with t he beams set in t he base of theconcrete pier. The concrete base could be constructed during thecold weather period bu t it would n ot be feasible to pour th econcrete columns during the winter months (on either of the twodesigns). The superst ructure could th en be const ru cted on t heskeleton bents and should be completed by th e end of th e ex-tr emely cold weat her. About April when war mer weather ar rives,th e bent s could then be encased in r einforced concrete, the con-crete decking poured, and the bridge would then be ready fortraffic. This method would be more expensive in total steel used,but would require about 25% less reinforcing steel. It would allowa more balanced work schedule by taking the maximum workloadoff of the final two to three months and allowing a balanced or fullwork schedule dur ing the cold weather month s, thu s insur ingcomplet ion on schedule, bar r ing serious accident s.

16. A low-level fixed br idge is offered a s a less expensivesolution to provide a river crossing before the winter ice season.This bridge is designed t o withsta nd damage by floods and wouldallow tr affic at all times when th e river is below a lOofoot level.The piers, on 69.foot cent ers, consist m erely of a sheet m eta lpiling caisson driven t o bed rock, excavated and t ied in to bed rock with a reinforced concrete slab, refilled and compacted with rock an d gra vel, and sealed with a reinforced concrete cap. Two 36”

I-beam girders, with 12” I-beam saddles to support M-2 tr eads,will suffice for a one-way t raffic class-50 bridge. Const ruct iondeta ils a re sh own on t he a tt ached dra wings, Plan B. Designcomputa t ions, cost estima tes, and a list ing of items of materials




an d equipment th at may require special supply action a re in-cluded a t Incl8. About six to seven weeks construction time by oneConstruction Company reinforced is estimated for completion of this bridge. The estima ted total cost is $498,053.00. All mater ials

above th e piers can be salvaged i f i t is desired to rem ove th e bridgeat a futur e dat e.

17. A rest r icted two-way class-50 low-level br idge, 20’ 2V2”width, basically similar to th e one-way bridge described in pa ra-graph 16 above, is offered for consideration. A wider pier, addit ionof a third 36” I-beam girder and a third M-2 tread, with wider fill

between treads, is the only difference. This bridge will allow two-

way traffic for all military vehicles except those exceeding a widthof about loo”, and provided a maximum load of 90 tons per span isdistributed between the three 36” girders (30 tons allowable loadper girder). Construction details are shown on attached drawings,Plan C. Design compu tat ions, cost estima tes, and a list ing of items of mater ials and equipment t ha t may require special sup-ply act ion a re included a t Incl 9. About ten to twelve weeks’cons tr uction time by one Const ruct ion Compa ny reinforced is

est imat ed for completion of this bridge. The est imat ed total cost is$672,843.00.

18. An unrest r icted two-way class-50 low-level bridge, 24’ inwidth, basically similar to th e one-way bridge described in pa ra-graph 17 above, is also offered for consideration.2Four 36” I-beamgirders will be required. A corr ugated sheet meta l decking with4” concrete wearing surface, similar to the decking designed forthe high-level bridge, is proposed for the un rest r icted two-waytraffic bridge. A schematic drawing with cross section and eleva-t ion is at tached as Plan D. Design computat ions, cost est imates,and a listing of mat erials and equipment t ha t may require specialsupply action a re included a t Incl 10. About twelve to four teenweeks’ const ruct ion t ime by one Const ruct ion Company rein-forced is est imated for complet ion of th is br idge. The est imat edtota l cost is $702,093.00.

19. If bed rock could be reached a t depths less th an 20 feetbelow the river bed, and if the overburden allows an easy penetra -t ion of th e sheet piling, it is possible th at th e const ru ct ion t imecan be reduced for the type of bridges shown on Plans C and D.






(restricted t wo-way t raffic). It does not appear economically feas-ible to plan for two-way maximu m loads. Such t raffic could beeasily cont rolled, and besides it would be un usua l to expect suchallowance on Korean bridges. Super st ructu re on t his br idge is

salvageable.

25. It is not considered economically feasible to complete abridge as shown on Plan D (un rest ricted two-way t ra ffic) unt ilafter th e thaw season, due to difficult ies tha t will be encoun teredin laying a sur facing mater ial on the bridge during the ice season.Use of t imber decking would a llow complet ion in J anua ry 1953 of a similar type bridge, provided construction is au thorized without

delay.

26. A permanent bridge over t he Imjin River a t t he Teal siteis not pr esently foreseen a s of ma ter ial value to th e perma nentKorean t ransporta t ion system. The civilian needs are for a roadsystem between Seoul a nd Kaesong; the appropriat e locat ion foran Imjin River crossing for t ha t r oute would be at t he Honker site(CS 086968). A second preference would be at the X-Ray site (CT

095013). The Teal site is considerably upstream from a desirablecrossing for permanent value to th e Korean t ra nsporta tion sys-tem. Hence a permanent br idge at t he Teal site would be prima r-ily of milita ry value only. And if an ar mist ice is signed on thepresent ly un ders tood terms, the Imjin River will probably be inthe neutr al zone.

V. RECOMMENDATIONS

27. Const ruct ion of a low-level fixed br idge over t he ImjinRiver at the Teal site is recommended. It is fur ther r ecommendedthat a bridge be approved which is basically similar to the designshown on Plan C (two-way restr icted t raffic). ,



APPENDIX B

HEADQUARTERS2D ENGINEER CONSTRUCTION

APO 971

ACKNOWLEDGMENT

P

IGROUP

Acknowledgment is made of the valuable assistance renderedand techn ical dat a furnished for prepara tion of the engineeringreport by the following Korean engineers :

Mr. Chae Kyong Yol, formerly Chief, Bureau of Public Works,ROK

Messrs. Han In Sun and Rim Bon Kun, Seoul Bureau of PublicWorks

Mr. Chan g Youn g Sheng, Chief Engineer , Kyong Gi Do [Ky-onggi] Province

Mr. Kim Y. K., Chief En gineer , Korean Na t iona l Railway.

91




HEADQUARTERSEIGHTH UNITED STATES ARMY KOREA (EUSAK)

OFFICE OF THE E NGINEERAP O 301

OPERATIONS ORDER 13 Augu st 1952NUMBER 33

1. 2d Engineer Const ru ct ion Group:3

* * *

H. Submit design , da ta , specifica t ions, an d const ructionplans for class-50, two-lan e Hi-Level Highway Bridge in the vi-cinity of Teal bridge, CT 175057. The informa tion to include:

(1) Data compiled on river bottom soil structure and bear-ing capacity.

(2) Profile of river stages listing low, high, and mean water

levels.

(3) Cross-sect iona l plot of river bed elevat ions.

* * *

FOR THE ENGINEER:

s/W. J . Himest /W. J . HIMES

Lt Co1 CEOperations Officer



APPF,NDIX B 93

OFFICE OF THE CHIEF ENGINEERGHQ, FEC

22 August 1952

FRQM: Maj. Ander sonTO .. Maj. Pu sey, EUSAK Engr Sec4

Recently, someone from your office requested information onriver bed conditions for a specific locat ion. We had nothing readilyavailable and were una ble to give you a ny dat a t hen. Subsequentresearch r evealed some dat a from which the at ta ched study wasprepared by a geographer in our Foreign Map Library and editedby a geologist. I don’t know if this will help you at all a t this dat e,but am sending it t o you in hopes that it will. Please let us know if examination in the field reveals errors or omissions in this report .If we can help you in an y way again, please let us know.

s /Andy

t /E. G. ANDERSON5

Chief Resear ch and Ana lysis BranchIn telligence Division

1 InclStudy




RIVER BED CONDITIONS

ATYONGSAN-NI FERRY, IMJIN RIVER, KOREA

FOREIGN MAP LIBRARYINTELLIGENCE DIVISION

OFFICE OF THE ENGINEER

HQ FEC

AUG 1952



APPENDIX B 95

FOREIGN MAP LIBRARYOFFICE OF THE E NGINEER

HQ FEC

River Bed Conditions a t Yongsa n-ni Ferry,6 Imjin River, Korea

The Imjin va lley is loca ted in a region of low moun tains,formed on a bedr ock consist ing pr incipally of met amorphosedsediments of p r eC amb r i a n age. These meta - sed imen t s arewidely distr ibut ed in the dr ainage area and consist of qua rt zite,limestone, phyllite, an d am phibolite with admixtur e of mica

schist an d schistose gneiss. Also, some porphyry, gra nite, andbasa lt a re found locally in the dist r ict. Among these rocks, onlythe more resistan t materials, such as quar tzite, phyllite, etc., ar etr an sport ed and deposited in t he str eams, though some basaltma y come from local ar eas of outcrop.

At an ear lier s ta ge, the Imjin River cut its valley in appr ox-imately its present locat ion, and that valley formed th e avenue of movement for a ser ies of basalt flows, par t ially filling it. These

basalts now extend to the village of Yongsanni on the west side of the valley and to Kumgong-ni on the east side. The present Imjinflowed on t his basa lt su rface and has since cut th rough t he exist-ing valley, showing cliffs of basalt a s far as Yongsanni on t he westside and far th er downstr eam on the east . Terra ces, indicat ingsevera l sta ges of downcut t ing, ha ve been formed a long thestream.

The influence of the tide acts on the wat er level of the r iver a s

far as Korangp’o-ri. Changes of level at th e Yongsann i ferr y areas follows:

Rise of level at spr ing high t ide . . . . . + 0.9 metersMean level of the r iver . . . . . . . . . . . . . 0Fall of level at low tide . . . . . . . . . . . . . - 0.5 meter s

Floods of th e Imjin a re notable and ma y ra ise its level about15m. above the mean . Below are dat a for severa l past floods:

Date

Wa ter level Precipitation (in millimeters)

above sea Du rin g A t I’chon At Yonch’on

22-23 Aug 1922 15.67m. 18-23 Aug 600-700 300-350




Wa ter level Precipitation (in millimeters)

Date above sea Du rin g A t I’chon At Yonch’on

1 Au g 19337 15 .63m. 17 Jul-1 Aug MO-600 400-450

21 J ul 1924 16 .09m. 11-27 Jul 750- 550-600

18 J u l 1925 16 .37m. 15-27 Jul 6 0 0 - 550-600

In t his par t of th e s t rea m , ra pids are foun d at two places: to thenorth (upst ream from Yongsan-ni) at Cha jip’o, and to the sout h(downst ream) nea r Changsan-ni. While bedrock is not r eportedvisible in the st ream at th ese points, the situa tion is suggestive of bedrock cont rol. The lack of alluvial terraces or of broad alluvialplains at any point along the river in this sector plus the presenceof ra pids indicat e a st ream a ctively engaged in downcut ting, a

condition which does not allow for accumulation of any apprecia-ble alluvial mant le. Fu rth ermore, upst ream from Chajip’o, bed-rock is exposed along the st rea m bed; at Seoul, in t he sa megeom orp h ic region , bedrock is exposed in th e bed of th e H an River.These factors indicate a lack of any general alluviation of streamvalleys in th is par t of Korea. It should be noted, however, to th ewest of the Imjin, tr ibut ary valleys are apparent ly alluviat ed tosome depth. This is probably only as a result of one-time damming

of th ese local t ribut ar ies by th e basa lt flow in the main valley.The longitudinal section is from a reconn aissance of the RiverDept., Korean Government General’s Office, 1929. Between therapids of Cha jip’o an d Chan gsan-ni, thr ee deep points in t hest ream bed ar e indicat ed: Koran gp’o-r i, 3.5 meter s below meanwater level; a point 900 meters above Yongsan-ni ferry, 5.7 metersbelow mean water; and near Imjin-ni, 10.5 meters below meanwater . As t hese occur at th e apexes of severa l meander curves,th ey ar e th e points of most active str eam erosion an d, in an

actively downcut ting str eam, may be assumed t o be on bedrock.By connecting these deep points in the pr ofile, we have what maybe assumed to be the maximum depth t o bedrock beneat h th eriver surface.

Though th e actua l river bed a t Yongsan -ni is ma sked byalluvium, th is is considered t o be th in. At the ferry, the r iver is 2.4met ers deep. As bedrock is assumed t o be 5.7 meters below thesur face, 900 meters upst ream, there is a difference of 3.3 meter s

represent ing the maximum probable depth of alluvium in th eaxis of the st ream. This figur e may probably prove to be high, asth e bedrock surface genera lly rises in t he st ra ight st ret ches of a



APPENDIX B 97

stream, for t here the effect ive stream erosion is not so great as a tthe apex of the meander cur ve. On t he west bank of the Imjin a tYongsan -ni ferry, alluvium may be slight ly thicker th an on th eeast , this especially below the mout h of the sma ll t ributar y just

south of the ferry.



Appendix C

EXCERPT FROM L IBBY HI-LEVEL HIGHWAY BRIDGE, A PAPER

SIGNED ABOUT J UL Y 1953 BY MAJOR WILLIAM C . C A R T E R , J R .,OPERATIONS OFFICER, 84~~ E NGINEER BATTALION

LIBBY HI-LEVEL HIGHWAY BRIDGE

General Description

.Length and Spans: 1074.2 feet, with eight spans 121 feet and one

span 104 feet.Height: 49 feet t o bottom’of I-beams at mean low tide. 79 feet from

bottom of caissons to top of deck.

Roadway: 22-foot tr aveled way; 25-foot overall.

Piers: Eight piers ma de of Yawa ta sheet pile, type #3-5 pileswide by 19 piles long, driven t o bed rock (average e leva t ion -15 feet) and cut off at elevation + 15.00 feet . Caisson muckedto firm bed rock and filled with concrete. Reinforcing tempera-ture st eel placed in the top 10 feet of caisson. Above elevat ion+ 15.00 feet the piers rise 44 feet consisting of two reinforcedconcrete columns 4 feet wide by 5 feet long spaced 10 feet apar twith an int ermediate stiffener 4 feet wide by 3 feet deep, and acap 4 feet wide, 4 feet deep, by 22 feet long.

Beam s: Five 4%inch built-up beam s spaced on 57-inch centersfrom bridge centerline.

Decking: %-inch corr ugated sheet m etal subdeck, 25 feet wide,welded t o beam s, covered with 7V4 inches of reinforced con-crete from top of 3-inch corrugation.

Appr oach roads: 30 feet wide covered with 12 inches of crushedbasa lt base an d 4 inches of cru shed one-inch aggregate.

Class: 60 ton two-way.



Appendix D

L OG OF LIBBY B R I D G E , C OMPILED BY MAJ O R WILLIAM C.

C A R T E R , JR., OP E R A T I O N S OF F I C E R , 84~~ E N G I N E E R

C O N S T R U C T I O N B ATTALION (22 NO V E M B E R 1952-5

J ULY 1953) AN D M AJ O R S AM E . F A I R C H I L D, HIS

P R E D E C E S S O R I N T H AT P OSI TI ON

LOG OF LIBBY BRIDGE

9 October 1952

Notified by 2d Engineer Construction Group that the 84th

En gineer Const ru ction Bat ta lion would build a high-level perma -

nent-type bridge at X-Ray site on the Imjin River. Design and

details forthcoming.

14 October 1952

A list of equipment and special materials is being prepared,tha t will be needed to build bridge. A reconn aissance of Bat ta lion

bivouac area is being made in the vicinity of X-Ray Bridge site.

Plan s ar e being made t o move Compa ny A, Compa ny C, and H&S

[Headquarters and Service] Company to this proposed location.

Submitted tentative equipment list to Group C.O., and he

suggested that plans be made to utilize as much [as possible] of

the equipment now in use or will be in use at Teal low-level

br idge.’ At pr esen t we don’t kn ow when the X-Ray Bridge job willstart. Have not received any plans to date.

15 October 1952

Got O.K. from 1s t Mar ine Division to occupy ar ea nea r X-Ray

site. Were told this battalion must construct “bug-out” road in

rear of area. Now, have area swept for mines before starting

prepar at ion of ar ea for quar ters.

23 October 1952

Group shipped by ra il 21 pieces of 60’ sh eet piling with differ -

ent design from original type we had already received. Are un-

loading at Munsan[-ni] siding and holding for disposition.




25 October 1952Got verba l notificat ion from Gp : J 2 tha t the following equip-

ment was being shipped from Pusan :

2 Pr imary Rock 1 Aggregate Heating

Crushers Plant2 Secondary Rock 3 Shower Units

Crushers 18 20’ x 40’ Tarps7 14 S Mixers

34 Herman Nelson

4 Dozers Heaters4

1 Yl%vo-compartment

Aggregat e Plan t

27 October 1952Received plan #A-1-39, showing cent er line and plot plan of X-Ray site. Received profile, drawing #A-l--39 for proposedX-Ray [Bridge].

28 October 1952Received Group Operation Order on X-Ray High-Level

Bridge, #84-376 . 5

29 October 1952Star ted assembling floa ts to drive Armco piles6 upstream

from piers t o get bedrock profile and also to support cable fasten-ing.

1 November 1952Mar ines clear ing mines in vicinity of nea r shore approach t o

bridge. Preparation being made to drive two Armco piles (one on

each side) to suppor t cable across river a nd to dr ive one pileopposite each proposed pier a pproxima tely 175 upst ream to ob-tain bedrock profile in r iver bottom and also to be used as anchorpiles to drive caissons.

9 November 1952Completed dr iving two Armco cable anchor piles a cross r iver

and strun g anchor cable.

Received plans for permanent high-level bridge. The followingquestions came up: Is 3V4” enough thickness for concrete deck slabwhich uses 1” width of reinforcing rods? Whether or not the



APPENDIX D . 101

corrugated sheetbmetal on decking will be overlapped lat era lly?How many fixed and how man y free ends of 36” beams? A detail of

free end of beam? The size of pier ba se? The height of colum nsection? The n umber of reit iorcing rods in section C-C7Whether or not che base of pier wen t t o bedrock?

column?

Also received bill of materials from 2d Group for bridge. Thiswas return ed to Group for corr ect ion .

10 November 1952Drove test A~UICO piles 125’ upst ream opposite pier 7 and pier

6. These piles to be used as test for depth of bedrock and a lso [as]

anchors for caisson construction. [We obtained the following r e-sui ts:]

Length of pile:Time:Depth of river:Penetration below river bottom:Total below wat i* [surface]:

#6 #7

38 feet 38 feet1650 11409 feet 6V2 feet20 feet 17 feet[29 feet] 23l/2 feet

[Additional resu lts:]

Depth of river:Penetration below river

bottom:

#3 #4 #5

8V2 feet 8V2 feet 9V2 feet

2OV2 feet 2lV2 feet lBV2 feet

11 November 195. .

Received corrected (change 1) copy of 2d Group’s BM [bill of

ma ter ials] on X-Ray Br idge. This was checked by Ba tt a lionagainst plans a nd changes recommended to Group.

12 November 1952Checked with Gr oup on plan s an d BM.&fer to quest ions

listed above on 9th and 11th Nov. No answer was given by Groupon deck slab or corr uga ted sh eet meta l. They are tr ying to getmore da ta on meta l. Group issued another sheet of plans (profile)showing which joint s were fixed and which were free. Didn’t give

a det a il of free end joint .I t was O*K. by Group to use new dimensions for t he base of the



102 BRIDGING TH E IMJ IN

pier a s resulted by actua l measur ement s of type III sheet pile-giving 1 ft. increa se in length a nd 1 ft. increase in width .

The heights of column sections were given a nd marked on theplans.

l’

The number of reinforcing rods in cross-section of column C-Con plan s was esta blished as 22. Inser ting 2 more on dr awing.

The ba se of pier was to go to bedrock.No decision was made on H-beams being used to anchor base of

pier into bedrock.No decision was made a s to wheth er erection plates would be

placed or just the bolts before pour ing th e base of th e pier.

Group O.K.‘d the a dditiona l cha nges of BM an d issued acorrected copy (change II) of BM.

17 November 1952Notified by Battalion S-48 that 45# i!Y’ cha nnel iron was not

avail-able as called for on X-Ray BM. Called Maj. [Willard] Norris(Gp. [S-13) and h e said to go ahead and req[uisition] 15” channel

leaving off weight . He said if 33.9# iron is substitu ted it would beO.K.

Capt . Long at Group is designing a sheet pile dr iving headth at will drive 2 piles a t a time. This may call for redesigningtemplate for driving caisson.g

24 November 1952Group notified Bat ta lion last night that batch plant is not on

hand at Pusan an d 27 E mixers not available.Major it ems n ow on h and include one 300 BBL [300 barrel]

cement bat ch pla nt complete. One 80 to 150 [tons per h our ]aggregate dryer arrived Muns a nn i this A.M. to be unloaded P.M.Sheet piling arriving on job. Work.progressing on cau seway, bothbanks.

A Company began erecting large mainten an ce building on 23Nov. Area muddy due t o freeze and th aw act ion. TYucks..hauling

’rock ba se for X-Ray equipmen t yard, roads, and buildings.

25 November 1952Aggregate dryer does not h ave UD 1 iA power.un it with t he unit. Maj. Norr is, Group S-3, [wasphone, [by] Carter,lo about 1730 24 November.

[generating]] advised by



APPENDIX D

27 November 1952Cal. [ R a y m o n d W.]

Beggs, Group Comm an dingOfficer, visited Battalion26-27 November retu rn ing10 A.M. today. Discussedplans for executing X-Rayproject w/general approvalgiven for all plans exceptmodification of aggregateload ing in to dryer andmethod of mixing an d plac-

ing concrete in caissons.About 1730 26 NovemberCal. Egg le s t an l l i n fo rmedCal. Beggs tha t a 34 E paverwas expected in Inch’on fromYokohama 11 December .

Pr esent plans a re as fol-lows:

Pr ogress schedule as per

Figure 64. Major William C. Car-ter, Jr., project manager for con-st ruction of th e Libby br idge, in

front of the completed structure.drawing 376-1, sheet 2, dated 26 November 1952, approved ver-bally.

Plans [are] to cons tr uct st raight -line gra vity-follow concretemix plant along cliff on west bank th en move to eas t bank an dremove on completion of piers a nd before spr ing high wa ter .

Plan to batch aggregate in plant but to mix and place concretein caissons from t hr ee l/z-cu.-yd. mixers ar ra nged near caisson.

Haul batch in 3-compartment dump body. Place concrete in cais-son from W2 yd. clam bu cket .Corr al1 concrete cur ing c ab i n s12 will be used to both cure fresh

concrete a nd as a work plat form to place concret e. Also as ashelter when fit t ing forms and placing reinforcing steel.

20’ x 54’ shed for concrete stora ge ar rived today by tr ailer.

10 December 1952Col. Beggs visited during lunch 9 December and gave decision

on caisson pile dimensions as follows: 19 piles length and 5 pileswide plus corner pile 4 corners .

At 1700 hrs. talked with Capt. Long, Gp. Equip. 0. ,13 and wasadvised: UD 14A power un it for aggregat e dryer being a irlifted t oK-16. l4




Aggregate Elevat or is on a boat from YED? Rotar y drill is

coming-don’t kn ow wher e or when . Bat ch plan t less sca les isshipped via rail [from] Pu san. Sheet pile heads-3 ea . -adapter16ready 11 or 12 December.

10 December 195~Aggregate plant at Marine Bridge consist ing of one primary,

two secondaries, went int o effect ive pr oduct ion this af t i rnoonafter 4 days of t r i . a l s and adjustment s. Output indicat ed excellent

coarse aggregate with doubtful fine aggregat e due to un knownamoun t of fines and suspected s ilt and/or colloidal ma t ter . Testsamples picked of&onveyor .&cha rge this A.M. about 1130 and .

again about 1430 ‘were ta ken back by 2d Gp. for s ieve analysis-.

along w/specimen .from Imjin River sa nd.Concrete ba tch plan t in 3d da y of erection on far sh ore. 20' x

54' cement shed going up on near shore. Equipment shop corn-pleted and roof going on carpenter shop. Materials yard about 12

laid out with appr oxima tely 8 tr ailer loads of lumber on han d.

Marine Br idge gravel appears u nlimited with 20,000 cu. yd .take possible with in easy 8 [cubic] yd. pan r ange of plan t? Plant-is fed by dozer and ramp bulkhead. Shovel loading out gravel fillto. X-Ray yard.

Fender sheet pile on West causeway going in to protect t h an -nel erosion of causeway. X-Ray pontoon bridge removed 9 Decem-ber .

17 Dece.mber 1952

Staf lvis i t by Col. Egglestan , Cal. Norris,18 Capt. [Edward P.]Klot ih , :Gp. Ex. Officer, SW3, S-4, respectively, was made 14-15

December. Conference concerning Teal, Freedom Gate, .an dX-Ray problem was night of 14 December in CommandingOffi-cer’s tent. Among problems discussed concerningX-Ray were thefollowing:

lV2 [cubic] yd. [power shovel] now at Teal will be requiredth ere th rough J an ua ry taking off slopes of Nort h approach af t i r .

bridge steel an d piling are complete.There was general discussion of aggregates for XiRay. Initialsample from Marine Bridge plant taken a bout 8 December shows8.5 fines passin g #80 screen. lg The san d appear s to ha ve an excessof clay and silt, and coarse contains a large quant ity of sand and in



APPENDIX D 105

addition is coated with some clay and silt. It was generally be-lieved that mater ial passing th rough dryer would burn off an dblow off some of the fines . Wash ing is not desir able due to ex-

pe t t ed low tempera tu res. Aggregates at Teal are generally

clean er tha n t hose at Mar ine Bridge. Dump t ru ck support wasdiscussed. It was genera lly agreed tha t river san d from X-Raywould serve the pu rpose, but it t ests out 62.9% ret ained on #40an d 31.2% reta ined on #60 screen.

Equipment forecast by Gp. as of 14 December was as follows:34 E pa ver-Inch’on-24 December phoned in by Maj. [LeonardC.] Na sh of Gp. Batch plan t-have car nu mber but don’t kn owwhen it will ar r ive. Aggregate loader -conveyor on a boat from

YED. UD 14A power unit for aggregate dr yer wa s t oo big fora irlift an d is coming up by r a il somet ime. Rotar y drill st ill atPu san. Adapter h eads for sheet piles will now be ready noon 16December. Have had a one-two day ready report for more than aweek n ow. The adapt er h ead is necessar y to set first pile an ddelaying th e star t of actual const ru ction at X-Ray.

On 16 December a call to Capt. Long, Gp. Equipment Officersaid pile adapters were to be ready at noon. Call back from Group

says power failure has delayed completion to Thur sday 18 Decem-ber. Group Ex[ecutive] Officer informs tha t car nu mber on ba tchplant turned out to be car number of car that brought up cementbatch plant . No commercial batch plant will arr ive in near fut ur e.Order given to Company A 16 December to proceed to constructour own plan t. This has delayed concrete production severa l days.

17 December 1952,1315 hrs.

J ust ta lked with Lt. Col. Norr is, Gp. S-3, an d request dumptr uck plat oon (16 trucks with support ing mecha nics and su per-visors) to report 19 December. To be housed H&S Co.

Norris reports two hours’ work remaining on sheet pile anvilhead. Will call when complete. Request s redesign of st eps andrerequisit ion of ma teria l to be changed to X-Ray.

17 December 1952, 1715 hrs.Group Ass’t . S-3, Maj. Nash, has called and inform [ed us that]

16 dump trucks with drivers and support to arrive 19 December.Decision of Commanding Officer to move aggregate productionplan t from Marine Bridge to Teal. S-3 concur s. Marine Bridge



106 BRIDGING THE IMJ IN

aggregate ha s too hea vy a coat ing of silt an d clay. Compa ny A’s

rock crusher crews to move up on 18 December.

18 December 1952UD l4A power un it for a ggregat e dryer ar rived at Munsa n

ra il head yesterday. Today at 1630 checked rail yard and found six604on aggregate bat ch bins ha d a rr ived.

Aggregat e plan t moved Mar ine Bridge to Teal on 17 Decem-ber. 16 dump trucks to arrive tonight to haul aggregate from Tealto far shore X-Ray.

Adapter head for sheet piles ar rived last night . Too big. Spentday cut t ing it with torch down t o size. If it fit s can begin firstactual constr uction on caissons tomorrow.

20 December 1952At 0845 hrs. the lV2 yd. Manitowoc crane r igged with leads ,

5000# ha mmer, on West cau seway near pier 6 picked up a 40’sheet pile. As crane swung from W to S th e machine began to tilt

to the S. Tracks were on E-W axis. Maj. Car ter, Capt . [Willard T.]Pflueger, W/O [Harry] Cooley were observing opera t ion; a ll ho lo

- lered simultaneously, “drop the hammer .” Operator at tempt ed & -

stop swing a second then jumped. Rig toppled sideways to t h e%Damage appear s to be broken boom section, twisted leads, twistedand broken cat walk. Damage to machine unknown but believedslight. Immediate efforts began to remove damaged sections andupr ight machine.

30 December 1952.

X-Ftay project progressing slowly. Pier 6 sheet piling going inwith 6 piles to 15 penetration as of 29 December. First pile drivento 30’ penetration from causeway to bedrock. Remaining piles tobe driven t o 15 un til all ar e conn ected t hen to bedrock.

Concrete mix plan t erection proceeding. A tota l of six (6)aggregate batch bins arr ived: two to feed aggregate dr yer , two inmix plant to feed volume measu re buckets for each mix, two to be

;

ret ur ned t o. Gp. S-4 as excess.Coarse aggregate production at Teal is slow. 80 cu. yds. loaded

out first day of operation. Frequent breakdown of crushing equip-ment. 595th [En gineer Dump Truck Compa ny’s] dump t ru cks .

U6) hauling aggregate from Teal to far shore X-Ray. ‘Trucks as of today begin h au ling sand from Spoonbill to far shore.



APPENDIX D 107

E xca vat ion t o elevat ion 53 [feet a bove mea n s ea level] pr oceed-

ing on West abutment . Clay spades an d pneumat ic tools requiredfor all excavation.

Car pent er shop completed an d erection of concret e cur ingshelter underway. Materials storage yard laid out and organized.Operations mce car penter work finished 29 December.

*’ Compa ny A an d Compa ny C hur ting for m an power. Eachcompa ny ha s men working to complete Teal.

Many items required for first concrete pour have not arrived.Gp. advised on 29 December of shorta ges. .

11 January1953Sta tu s of project as of 1200 hr s. 11 J an ua ry 1953 follows:Sheet piles pier 6 all driven to within [at least] appr oximately

5’ of bedrock with about V3 to bedrock. Penetrat ion averages 30’below cau seway which is a t a bout plus 15’ MSL.20 2100 GPMp ump2 1 with lowering at tachment s and hose is on site prepared todewater. 3/4 yd. clam is on site prepared to excavate. Piles will becut to e lev . 15.00 per change in caisson design from elev. 10 toe l ev . 15 n ecessitat ed becau se elev. 10 would be un der wat er mu chof the t ime. Well dr ill rig on ha nd to dr ill dowel holes if bedrock surface is not rough enough to prevent movement of caisson. -

Cent ra l concrete mix plant is set up and awaits 34 E paver.Pa ver h as been report ed for m ore th an two weeks as on th e way, a tPu san , on wa ter between P usa n a nd In ch’on, an d in h old of ship a tPu san. Gp. S-4 advises as of an h our a go it is now on wa y via

water to Inch’on. Aggregate dryer operated first time on 10 J a n u -

ary. Wat er heater operat ed on 11 January.All coarse a ggregat e r equired [is n ow] on fa r shore[;] 900

[cubic] yds. [ar e th ere], only 700 [are] required. Hauling as of thisdat e to stockpile near shore. Sand stockpiled on far shore, andsour ce on river downst ream far shore available for fur th er r e-quirements.

West approach road laid out with a curve to the r ight on nort hwith 5%+ grade an d cur ve to sout h on left with 8% grade. 36”culvert going in at st at ion 12+51.22 Slope st ak es going in on

approaches. Necessar y str ipping completed. Eart h moving equip-me r i t must come from Teal on completion of that priority project.West abutment near ing complete excavat ion to elev. 53 MSL.

Gp. CO., Col. Beggs says O.K. to not use form on abut men t inview of ’ rock condit ion of excavat ion. South wing wa ll will be



1oa BRIDGING THE IMJIN

stepped to suita ble foundation. No wing wall necessary on N side.

Timbers laid t o car ry lV2 yd. Manitowoc which will drive pier7 and for lV 2 yd. P&H which is enroute th is date from Teal to drivepier 8. P ile in place.

Ca rp ent er sh op is work ing on first set of form s. Rein forcing rodfabr icat ion is underway. Mat erials st orage is fully opera tiona l.48” built-up bea ms to begin a r r iving coming week after railembargo lifts on 13 January, 8 per day. Cement on ha nd. -

We are needing welding equipment an d cut ting torches butmust wait t int i l Teal finishes.

Excess supplies and equipment ar e being moved daily fromTeal. Company A an d Company C manpower a t Teal par tiallyreleased on 10 J a n u a r y .

Weather past , ten days has r anged from 42O to 2’F. Only oneday of real warm weather.

16 January 1953Plan s ha ve been cha nged by Army and Gp. in some part icu-

lars. Superstructure deck will be W2" thick from steel deck valieyto top of pa vemen t, 7” at cur b . Const ru ct ion joint between s lab an dcurb. Lifts on pours, as planned by 84th and for which initia l set of forms had been built, were changed on column port ions to below45O cha mfer of 1' under stiffener and under cap.

Major changes ma de in wing walls, and Gp., Lt . Dameranha s been pr omising new design for 3 days now. We could havepour ed concret e tomorr ow if plan s h a d been finished. A tr ip to Gp.yester day produced half th e inform at ion required but no call

today on steel, which will have to be cut an d bent an d placed. 34 E paver, less drum, ar rived at I n&on yester day. We ar e

going ah ead with one 16 S mixer in centr al plant .Piling going in fas t ot i pier 7 today. lV2 yd. P&H crane moved

down from Teal r equires severa l crit ical pa rt s before drivingoperations on pier 8 can proceed.

26 January 1953 . ’ ,‘

Equipment deadlined and lack of equipment due to Teal pr ior-

ity cont inues to delay seriously X-Ray job. Dur ing past week wehave critically needed lV2 yd. .crane for pile driving, h e day waslost for lack of an operat iona l air compressor when 500 cfmc lu t ch24 went out , and two days were lost limping along with a 210



APPENDIX D 109

Figure 65 . Excavation of cofferdam 6, begun by a3/4-yard clam bucket on

16 J an ua ry 1953. Shower u ni t a t lower left pr ovided hot wat er for cement .Twelve inches of ice on the Imjin provided access to the far shore on foot.

cfm in lieu of 500. Teal is releasing equipmen t as fast a s jobpermits.

Cont inuous problems a rise with pumps. Ignit ion t roubles dueto lack of good spark plugs, point s ar e main causes.

Three (3) 314 yd. cranes are down for [piston] rod inserts.Passed by V4 yd. Koehr ing day before yesterda y just as inser tsbegan to knock. Engine was full of oil. The clutch of the booster toboom hoist on 22B cau ses delays. Same crane needs new tracks.This machine has cost us valuable days in excavating caisson #6.

Lack of welding ma chines operat iona l has held up completionof concrete batch plant. For a week only one welding rig at X-Rayand it was on p ile dr iving rig or pier 6 most of t ime.

Steam r ig 3 car h e a t e r 2 5 came up last Monday 19 J anua ry atnight . Opera tor from 526th [En gineer Pa nel Bridge Compa ny]ha d never seen the ma chine before and was useless. A bad t ubehas cau sed delay in pr oper use of r ig. Believe it to be O.K. now.

Will place concrete in W abut ment today if plant an d V4 yd.mobile Buckeye hold together. Buckeye broke down a gain lastnight. It will not travel due to clutch but can be thrown into gear.

Finished driving piling pier 7 yesterda y to average pene t ra -




t ion of 27’. Lack only one foot to refusal on average it is est imated.Gp. CO. ordered Bn. C.0.26 on 25th to drive only 5’ a ll pile,

excavate, place whaler,” dr ive again . This procedur e will mate -rially slow work over present procedure.

A bad crack in piling, pier 6, makes a s mu ch water a s 2100GPM can pump from elev. 4% support in hole. Att empting to seal

,’ crack with grout from out side caisson using well drill rig.

27 January 1953Placed concrete in West abu tmen t an d wing-wall foot ings

yesterday. Fin ished placing at midnight . Began placing at 1700hr s. First bucket with 2% calcium chloride an d ru nn ing 110’ setup in less than 30. min. 1-2-3 mix2g used. Wat er was about 40°,

cement 32O, rock 125’, sand plus 300°. kquired 17 gal. water , attimes 18 gal., to get 2” slump.

Diver explored pier 6 caisson an d r eport s crack between 2” an d3” to bott om . Att em pt ed t o pu t cor ner pile in t o cover cra ck bu t d idnot succeed. Plan is to pump neat cement grout with well drill rigfrom outside when difKerentia1 is 3l wat er h ead flowing int ocaisson. Welder-diver to weld 2” angle iron over crack t his P.M.

_ Tempera tu re of 9’ this A.M. caused difficulties sta rt ing motors.Gp. C.O., Col. Beggs, on job last night and today. IXe commeno s

keeping engines running at night .Hurt ing for more cats 3 o to fill east cau seway, approach road

from ea st a n d cu t slopes for B Compa n y’s bivou a c a rea . Need m orewelders, Herman Nelsons, an d cranes.

28 Janzmy 1953Diver work ed in caisson pier 6 t oda y. P.M. was spen t set t in g 2”

angle iron down to rock against and covering crack. At 0200 thismorning diver finally completed tack-welding angle iron in place.Today he is to weld t ight .

Attempted t o grout with nea t cement from 29’ down usingwell dr ill. Pu mped bet ter than 30 [one-cubic-foot] bags downwhen pu mp quit, lost prime. Will try again.

Have 22B working ca isson #6. 2100 GPM pu mp, welding ’machine, 4” diaphragm pu mp, 55 GPM pump, . a n d well dr ill r igtied up on pier 6..

Mobile 94 yd. Buckeye w/clam excavating on pier 7 beginning26 J anuar y. lV2 yd. Man itowoc driving pile w/5OO cfm pier 8.

Need more pumps, cent rifugal, more welding machines and



APPENDIX D 111

cranes. lV2 yd. P&H r igging on near shore causeway to dr ivepiles.

3OJanua~yl953,0750 hrs.J ob has been stymied as a result of pier 6. On 29 Janua ry a

concret e cap wa s placed thr ough a t rem ie int o a form to block off a

*’ flow coming from u nder one of the piles tha t split. Apparent lylitt le wat er is coming in th rough t he crack. Diver clean ed outbottom, placed cap form, set tremie. Diver reports bottom unevenand leaks only under piling capped off on 29th . On 30 January we

will pump grout adjacent to split piling.On 31 Jan ua ry we will att empt to dewat er. If successful we

will muck out an d pour. If unsuccessful we willget divers, muck out , and pour.

Ca l Beggs retur ned [to] his Hq. on 29th. Visit made 29th byCol. Kel lyt l 8th. Army Operations, . a n d Col. Ribbs,32 8th Arm yEngineer Section.

Col. [Louis J .1 Rumaggi, 8th Army Engineer, ordered concrete

be placed aroun d bott om of caisson n ight of 29 J anu ar y. C.O.advised Gp . C.O. of conversation. J ob needs more cranes.lV2 yd.P&H rigged to drive on east causeway and should begin driving.pier 1 today.

Rig pu lled off of pier 8 on 29th an d began driving pier 7 topenetration. Standard penetration accepted at 50 blows per quar -ter inch. This move was resu lt of ear lier Gpi C.O. order to dr ivedown in increments an d excavat e an d set whalers. This policyreversed on 29 J an ua ry by Cal. Beggs a fter a closer st udy of

driving procedure an d soil conditions.Excavat ion of pier 7 will cont inue today after a ll piles reach

penetration.

.

Army is vita lly interest ed in depth of bedrock under caissons.Will drill down t omorr ow when grout ing [is] finished.

2 February 1953The Army Engineer, Col. Rumaggi, and Col. Beggs visited the

job yesterday. Col. Rumaggi, after having seen caisson, pier 6,remar ked a t noon to Col. Beggs, “We mu st consider all meansnecessary t o fully investigate foundat ion condit ions, a t the risk of delaying t he opening dat e [of th e bridge], as n eith er you nor Iwish to build a bridge such as th is one t ha t will fail.”

Pier 6 was dewat ered after t ime-consuming delays in gett ing

,

’




2100 GPM and 1000 GPM pumps lowered into hole and opera -

tion al. Last night we st ood on bott om of sou th end . Lots of wa ter insplit pile crack. Whaler now in bottom of pier 6. Col. Beggs saystwo Korean divers to come 2 Februar yto muck out bottom. A slabwill then be placed on rock bottom, allowed to set up two to thr eedays, then finish placing concrete. Man k i l l ed33 night of 31 [ Janu-ary]-1 [February] by boom failure on % yd. Buckeye clam pier 7.

9 February 1953Concrete was placed in pier 6 caisson beginning 5 February

and ending 6 February .a t 1900 hrs . The hole cont inued to makewater, and three large boils in the south end were evident whenlast mucking was complet ed. An air rock drill went 3’ int o rock near th e sout heast corn er prior to placing concrete.

Before placing concrete 50 sacks of cement were emptied int oth e hole th at was full of water a t t he t ime. The first 20 or sobuckets of concret e wer e lowered with a lV2 yd. clam wh ich pr ovedtime-consuming and created a great deal of wash-wave action. A

rig moun ted on four wheels run ning on t he t op 12” H-beamwhaler holding a 15” pipe by a collar served as a movable tremie

- which speeded up placing opera t ions .Pier 7 was quickly excavated to a depth of about 26 feet, but

rema ining excavat ion is slow. Mucking by hand due to la rgeboulders . No rock posit ively evident as of 2000 hrs., 8 February.

34 E paver a rr ived on job night of 8 February.Considering use of a “pumpcrete plan t” to place all concrete.

“Bug out fever” prevails past three days.

11 February 1953Col. Beggs, 2d Gp. C.O., visited job on 10 February, inspected

caisson #7, and ordered a concrete blanket placed i-n t he bott om,up to top of bottom whaler. A matter of 4’ of concrete. Allow to settwo days, dewater, and at tempt to place remainder in the dry. Bn.C.O. and S-3 favored and recommended placing ent ire caisson

but were overruled. 2 34 E pa ver is being readied for opera t ion.Excavation on pier 8 is slow, mostly by hand and a ir t ools due

to frozen ground. Now down to rock.Placed West abut ment wing wall. Vibra tor sheared cable t i t e r

V3 of pour placed Rodded remainder into form increasing cementone bag per V2 c*u. yd.



APPENDIX D 113

J ob badly needs two addit iona l cra nes, 3/4 yd., to meet sched-- ule. Vibra tors a re in critical cat egory along with r ivet hammer of

80-90 lb. size.Bn. C.O. approved scaffold design incorporating 3” angle iron

kicking against 48” beam with hook holding top member to 48”beam. -

B Compa ny pla toon is placing 48!’ beams and beginning disas-sembly an d assembly opera tions.

Adequa te coar se aggregat e is now on han d to finish job.

12 February 1953J ob was visited by Gen. Bowma n, AFFE En gineer,% an d

part y; Col. Kelly, 8th Army Engineer Section an d party; and Col.Beggs, Gp. CO. Col. Beggs left instructions to attempt to dewaterpier 7 after concrete blanket placed 11 Februar y has “set” twodays and finish p lacing concrete. 34 E pa ver was used to placeconcrete in pier 7, pour A blanket, and worked sa t isfactorily.Method of placing was thr ough a hopper moun ted on 15” Armco

piling supported on a four -wheel expedient dolly. A “bung’ [plug]was placed in pipe at bot tom to prevent water entering pipe on- ord ers of Gp. C.O. Meth od does not work su ccessfully un less rea dy

mea ns is ava ilable to keep elevat ion of bot tom of pipe at exactlydesired height.

J ob badly needs genera tors for n ight light s, welding ma-chines, cranes. A crane is needed to aid in fabricat ion of st eel, acra ne is needed to erect cur ing cabin, and a cra ne is needed forexcavat ing near -shore caisson.

Nmpc r e t e plan t less miscellan eous pipe and accessories a r -rived last night. Job had two welding machines operable as of lastnight . At least ten can be profitably used.

12 February 1953,130O hrs.C.O. just inform s th at Gp. called an d adds t he fifth beam to

bridge. This mean s loss of past weeks’ work in sett ing beams onfar shore aligned for four-beam spacing. .‘

13 February 1953Gp. S-4 visited job with Gp. Equ ip; Officer an d others . Dis-

cussed additiona l mater ials required a s r esult of adding fifthbeam to str ucture. Gp. S-4 says he ha s TWY’ed [cabled] J apan foritems manu factu red there.




Requested Gp. S-4 to ship all st eel decking.

14 Februav 1953Began placing concrete in dry hole, pier 8, about 2200 hr s., 13

Februar y. As excava t ion proceeded on pier 8, rock was encoun-

ter ed at elevat ion fYom 8’ to 10’ down. The r ock was r ot t en ,fragmented, broken and weat hered on top but moved out c o r np a r -

atively easily with clay spade. Sheet piles were undermined whenbad mater ial removed. On 13 Februa ry at about 1130 hrs. waterbroke thr ough n ort heast corn er in 200 GPM volume. Piles were

tapped down with free 5000 lb. ham mer , an d 99% of leaka gestopped. Foundation was mucked out again, washed down, andsteel set. Founda tion again washed down an d all loose mud andmuck removed. There appear s a rough bedrock surface ent irebottom. No slopes to the east are excessive or in a p l a . n e surface.The rock outcrops with an upward tilt to the south with the planestr at a lying about 35O downwar d an d level east an d west. Thisgives an excellent key to prevent slippage to the south.

All concrete was placed in the dry. Seepage water was movedahead of concrete. Pour completed 1655 hrs. 14 February.

15 February 1953;Gp. C.O. visited job on 14 February and observed dewatering

of pier 7 where concrete blanket approximately 4’ thick had beenplaced. The top of the sur face is soft , ma teria l has very litt lecementat ious materia l. The top 2” to 5” is cement sett lings and isconsolida ted but not fully set up. On digging down we find themater ial much har der, and more cement is with aggregat e.

Gp. C.O. orders excavat ion of a ll loose material. Pier 6 ques-

t ioned. Hold up work on pier 6 unt il decision is made. Muckingcrews worked P.M. 14 February and night shift cleaning out loosematerial. :

J ob badly needs three more cranes a nd more generators andwelding machines.

Lowbof5 dispatched to Gp. S-4 today to pick up KNR [Korean.

Na tional Railway] core dr ill r ig to get core out of pier 6. . -

: 16 February 1953’ b

i Loose mat erial free of required cement mucked out of-pier 7.Mater ial about 1’ under surface foun d to be suit able concret e in

’opin ion of Bn. C.O. an d Bn . S-3. Gp. C.O. advised A.M. of 15



APPENDIX D 115

Februa ry and inspection requested, but Gp. C.O. could not comeup until 16 Februa ry. Hole is hea ted and clean ed out awaitingapproval.

J ob is seriously delayed due to shortage of cra nes. Cra nes a reneeded t o ha ndle 43” beams, unloading an d placing; cra ne isneeded to load-aggregate bins; crane is needed to excavate pier 1;cran e is needed to place concrete; cran e is needed t o assist inerect ing forms, curing shelter s, moving heavy objects, loweringpumps, and set ting up for concrete opera tions. Available is % yd.tr k. mtd. [tr uck mounted] cran e used on cau seway, all jobs in

priority.Small pumps, 55 GPM and 166 GPM, are badly needed. Rivet-

ing hammers supplied have been too sma ll (60 size) or inopera tive(KNR). Fabricat ion of st eel is a full week delayed as result.

17 February 1953Lt . Damron advised to bend 6 dowel bar s in pedestals on piers

6,7 , and 8 since 20 dowels were u sed instead of 22 called for on

plans.

_ 18 February 1953Gp. C.O. au thor ized placing concrete in cofferdam pier 7 on

A.M. of 16 Februar y. Placing commenced at 1100 hrs. and wascompleted a t 0130 hr s., 17 Februa ry. Concrete was placed “in the

dry99

iOn] 17 February 1953, bulkh ead wa s placed n ear pier 7 for 34E pa ver t o discha rge int o remixer hopper of pumpcrete plant.36

Plan now is pump concrete into piers 6,7,8 from central location.Gp. C.O. au thor izes 5’ fa ll from bott om of pipe t o level of

placing in the form.Core dr ill from KNR thr u Gp. S -4 did not a rr ive.Forms going into pier 6, B pour , and steel being placed; cur ing

cabin going up on pier 8. Shortage of operational rivet hammersand cra nes is hurt ing job.

18 February 1953Lt . Damron advised tha t a ll dowel bars t o ha ve90’ bend, 5” or6” long, since, ‘/B” rods used instead of 1” rods.

18 February 1953Lt . Damron brought up plans for 78th job at Tongduchon-ni





APPENDIX D 117

Job needs cranes, vibrators, small pumps. Pumps appear to beour next bott leneck in placing concrete.

24 Februury 1953Cal. Ribbs, 8th Army Engr Section, is visiting job today. Dis-

cussed rivets versus bolts in 48 ” beams due to poor quality of rivet

stock an d un tr ained crews w/no buckers.3g

B pour , pier 8, completed in 2 hr s. 15 min. yesterday withoutincident using pumpcrete plant .

Drill r ig is down 6 ’8 and has produced 2” of core out of pier 6.‘Set ting forms an d curing cabin on pier 7 .

Pier 1 excavat ed to elev. 3 an d two piles E side are spr un g an dleak 400 GPM estimated.

Pile dr iving pier 2 proceeding n icely.22B placed in opera tion last night w/new m otor.

Ice too thin today for t ra vel. Placed assault boat into servicebetween causeways.

Began E a pproach today and had trouble breaking th roughfrost.

East abutment excavat ed today w/dozer.

- 27 February 1953Job was visited yesterday by Col. Beggs and Lt. Col. Parker,

34th Gp? The KNR core dr ill bar rel twisted off in the hole on 25February and efforts to extract were futile. Side of curing cabinwas removed and Fail in&l well drill was set into position to dr ill.Drill is down 3’ as [oflO hrs . today. Cal. Beggs directs that weuse r ock bit to dr ill 20’ ta king sweepings every 5’ and t henat tempt to take core rest of way. We will use an overshot withchilled shot t o get core. If bottom is not consolidated, the plan asexplained by Col. Beggs is t o drill two holes inside caisson, dr illholes outside caisson, pump grout. Redrill and if not consolidatedwe then drive piles 8’ away from present piles, excavate, and fillw/concrete.

Split piles observed in pier 1 at elev. 0 on excavat ion wer epulled. Pu lled eleven piles on SE quart er, corner pile on SE a nd 2

adjacent pile to corner. Reset ting piles t his A.M. Foun d pileswarped on bott om as much a s 18”. Penetrat ion blows cut back t o50 per V4”.

Pour B, pier 7, placed yesterda y, finishing a t 1915 hour s.Successful in’ a ll respects.



. . --

118 l% t I bGING THE IMJ IN

. .Excavat ing to elev. 58 on near shore approach as work site for

str uctur al steel. Abutment is excavat ed.

28 February 1953Last concrete aggregate loaded out of Teal on 27 February.

Ha uling scra p dirty aggregat e to X-Ray roads.Drill r ig drilling in ba se of pier 6 hit soft digging between

10'31 last night . Hole is down to 21’ and lots of sand washes intohole. Ordered curing cabin removed and upstream column B form

removed. Will drill two holes inside t wo columns an d pu t downwagon dr ill holes next t o pile an d a t tempt to consolida te bygrouting.

Col. O’Grady decided to jackham mer pier 6 out, r emove a llconcrete and sand, gravel, [and] cement , and repour by put ting ina blanket on bott om, then placing in th e dry. Former plan t oconsolidat e by grout ing will not be followed.

Company A will be assigned t he job. Causeway will be ex-tended from n ear shore when 7 and 8 ar e complete.

3 March 1953Gp. C.O. visited job 28 Februar y and a sked for another test

hole before we blow caisson pier 6.Gp. C.O. called 2 Mar ch a nd sa id Army En gr. ha s ordered

caisson pier 6 be grout ed.KNR drill crew ar r ived lat e P.M. 2 Mar ch to ret r ieve core

bar rel an d redr ill hole. Riveter s from KNR also ar r ived.

.Ra in night of 1-2 March left roads and work area very muddy.C pour, pier 8, completed 1930 hrs.,1 March.J ob needs additiona l light s for n ight st ructu ra l steel fabrica-

t io.n and genera tor for sa me.a /

4 March 1953,064O hrs.Col. Rumaggi and Col. Kelly visited job 3 Mar ch. No positive

decision on act ion t o follow on pier 6. Wagon dr ill continuing.Split piling pier 1 began pu lling.

Four welding machines in 78th for repair badly needed onstructural steel.

KNR could not retr ieve core bar rel unt il additiona l tools werebrought up. Will tr y again t oday.



APPENDIX D 119

4 March 1953, 0725 hrsm

C.O. advised at breakfast that Ca l . Beggs called last night and

said “blow” pier 6 an d excavat e.

5 March 1953Pour C, pier -7, was placed on 4 March without incident. Cur-

ing cabin , pier 8, was r aised lW2 feet.Pier 6 was dr illed, 40% dyna mite used t o blow top port ion of

caisson a nd downst ream column at 2225 hr s., 4 March.Pier 1 piles pulled on NE corner have been reset and dr iven to

penetration. Excavation for third time underway. All piles notedsplit have penet ra ted a st ra ta of rock 8”-10” th ick a t about e l ev . 2MSL. All have been type.111 Yawa t a 4 2 unpointed piles tha t do notgroove as well as those [of the] same type tha t come pointed.

Penet ra tion driving cont inues on pier 2.Shortage of operationa l welders is h indering progress on steel

fabrication.Ea st access road fill cont inues. .

Gp. C.O. advised 4 March th at aggregat e dryer could be re-

moved.Gp. S-3, Lt. Col. [Glenn J.] Allen, is on job in charge of

demol i shing pier 6.

7 March 1953,0635 hrs.Job progressing, but slowly with only two piers [ready for us]

to work on placing concrete. Pumpcrete plant works fine. Curingcabin in raised position works out O.K., however no more will be

built as weat her is beginn ing to modera te.Blasting, drilling, and breaking underway in pier 6 at depth of 6’ down. Hole makes water a t a slow seepage rat e. Although someof the concret e 6’ down is soft , there appear s to be a reasonablegrout mixed in with t he aggregates.

Pier 1 excavation proceeding very difficult at elev. + 2’ MSL.Large rocks do not en ter bucket of clam.

Should place D pour , pier 8, today.Beam fabr icat ion cont inues with first d iaphragming3 begun

yesterday. No bad sh ortage of cran es now. Aggregate bins a ndaggregate dryer removed yesterday and bins reset on near shore.

J ackha mmer tr eatment given to downstream column pedes-

tal of pier 7, C pour, where 4” “suck” occurred due to vibra t ingst iffener lost? Repair will be monolith ic with D pour .



120 BRIDGING THE IM J I N

10 March 1953,065O hrs.Gp. C.O. inspected job yesterda y. Lt. Cal. Allen, Gp. S-3, is in

personal charge of demolishing pier 6. They are nowabout 16 ft.down.

Gp . C.O.‘s verbal O.K. received to make a nd launch a cont in-uous beam from W abut ment t o pier 7, as a m ean s of gainingcontinu ity for r iveting, decking, an d diaphr agming crews. Willlaun ch t o pier 5 from W shore and remainder from near shore.

Pier 7, pour D, placed yesterday.Excavat ion cont inu es on pier 1. It begtin to ma ke 300-400

GPM last n ight .Diaph ra gming to be the same as in plans. Gp. and Bn. C.O.

will not buy X-bra cing th at does not bu tt t ight to 48” beams.J ob is h indered for [lack ofl cut t ing torches a nd ar c-welding

machines, Gp. C.O. and Gp. S-4 advised. Pan ic but ton pressed.

11 March 1953,0645 hrs... Rained a ll night . Roads were soft yesterda y with increasing

number of frost boils. Far shore causeway very muddy. Pile driv-ing hindered yesterday due to wet conditions and shut down last

- night.Pier 1 ma king 500 GPM, which required moving over 2iOO

GPM pu mp an d inst alling. Rock h olding u p a high pile was jackhammered out . Pump-packing collar was broken when pack-ing was tightened.

Forms going in E pour , pier 8.

J ob needs cut ting torches a nd welding r igs badly.

12 March 1953, 0645 hrs.Hard r ain and sleet cont inued unt il noon yesterday. All equip-

ment and mater ials were evacuated from both causeways. Sun-shine in P .M. helped dry u p a bit , but th ere is 2” of snow on groun dthis morning. No productive work except in car penter shop andsett ing forms pier 8 yesterday.

Fa r shore cau seway will require extensive fill. River level is .

higher th an norma l by four feet and very swift , eating off nea r ’

shore causeway upst ream an d on end.

13 March 1953, 0645 hrs.Temperature at th is hour is 22’F. Rain, sleet , sunshine, snow,

an d ha il interm ittent all day yesterday. Began moving equip-



APPENDIX D 121

merit back on cau seway far shore af t i r removing some muck an dfilling with firmer ma teria l. Adding sand t o roadway far shore.

Plan t o place cap on pier 8 today. Carpenters sett ing forms forcap on p ier 7. Pier 6 is excava ted d own below wha ler a nd n ow closeto bott om. Sump pump handled water u nt il yesterday P.M.

. Pier 1 exqavation is hard and slow in hard-packed boulders.

.’ Excavation proceeding in sand in pier 2. Pile closure in #3 [was]expected last night as only two piles morewere required. Plan totop down every 10th pile to hold against a washout if it comes.

River level from flood is not ser ious at this stage.

14 March J953 .

Placed pour I$ &r 8 , last night. High t ide of 25.9 [feet abovemean sea level] at 1554 h r s . [at] Inch’on w& at MSL 12.4 at 2005hrs. on upstream edge of east causevvay ,.l& n i g h t . 4 5

15 March 1953

H igh t ide at Inch’on 0459 hr s. 27.5' equa led high t ide at X-Ray0915 hrs. 1?.75 MSL. This tide partially floods near-shore cause-

way.Lack of welders and cut t ing torches ser ious ly delaying dia-

ph r agming and cut t ing of sub-decking.

16 March 1953High t ide at Inch’on, 0543 hr s., 29.5’ equa led high t ide at

X-Ray 0950 hr s ., 14.25' MSL. Th is tide floods m ost of cau sewa y.Gp. C.O. irispected hole, pier 6, early and, after inspection of

bedrock and bottom, gave orders to fill with concrete.Placing began at 1100 hrs . an d was completed at m idnight .All placing was “in the dry.” Approximately 5 GPM were pumpedperiodically from downstream end unt il all leaks in pile joints hadbeen cover6 .d . A mix 8:12:20 was u sed. Quality of concrete in pieris superior to requirements.

17 March 1953,171O hrs.Fair weather for a change with temperature above freezing all

day. High t ide at 1030 hr s. rose to elev. 15.2 MSL. (Figure 66)Highest t ide of spring expected tomorrow morning. Tide floodedboth cau seways an d badly eroded near shore. Timing of tidehinders hau ling in sand for concrete and r epairs a s t ide coverssand’ . bar.




. 4 J ob badly needs weldingmachines for steel prefab-[ricatling an d cut t ing torches.

Moving to near shore fromfar shore is order of th e day.Pumpcrete and 34 E ar e overand volume buckets for aggre-gate bins ar e being set on nearshore.

Figure 66.Work continuing onpiers 1,2, and 3 from submerged

Pier 1 whaler going in t o-night . E side of pier 1 pilingcaving in a t bott om.

Pier 2 down and whaler inbot tom nea r ly finished. Lotsof sand boils in h ole.

Piles on #3 reaching r ock at very irr egular levels. Driv-ing proceeding nicely.

Excavation of E abutmenteast causeway during high tide

on 17 March 1953.

progressed today. Shooting for

elev. 49.08 downst ream an d50.08 ups tr eam . Will hold to these elev[at ions] for wing wa llfooter bottoms. Will take abutment proper t o sound rock wher -ever located by dr ill test , probably about 49.0 + 6 inches. Crib-bing for st eel near shore out 300’ now.

19 March 1953,143O hrs.Drizzly ra in a ll day.

Pier 1 burst wat er un der th ird pi le from NE corn er on E s ide a tnoon. Hole was kept dry with t wo sump pumps pr ior t o break.Wat er now making about 400 GPM. High t ide was a t 1153 hrs.

Pier 2 sanded in 2’-3’ in downst ream side last night . Movingboth pum ps to upst rea m side on m iddle wha ler so we can excavat esand with clam a nd find a nd r emove boulder holding up pilewhere san d flowed in.

Piles on pier 3 a re on rock a nd exceedingly err at ic in depth

pat tern . St ill more dr iving to rock a ll ar oun d.J ob delayed for lack of cut t ing torches and welding machines.Will remove cabin on #8 Fr iday an d on #7 on Saturday.Mounted 50-cal. [ma chine guns] yesterda y and day before,



APPENDIX D 123

eight on bridge and four in a rea . Const ructing emplacement s forsame.

for34 E pumpcrete bulkheadoperation on near shore.

20 March 1953; 1500 hrs.Rained harder a s the day

near ly finished. Bat ch plant r igged

wore on yesterday and by 1600 hr s.th e clutch on P &H pile driver wa s un sa fe t o opera te due towetness of brake. Shut down rig.

Night crew reported for tiork as usua l, [but] rain was htiavierby 1900 hr s. About 2000 hour s Lt . Sco t t 46 received permissionfrom C.O. to shut down job as all cra nes were unsa fe and r a i t i wasst ill heavy.

About 2100 Col. Beggs called and asked about wea t& r andr iver. River was then a t a low sta ge, 11.0’ MSL at 2200 h r& Gp.C.O. ordered causeway evacuated. Evacuation was completed at0145 h r s .

At 0730 hrs. th is dat e, river was low. Bn. C.O. ordered equip-

ment t o resume norma l opera tions . Operations normal by 0930h r s

*At about 1055 hrs. I looked out the window of theOperatiotisShack a nd n oted water h ad r isen ra pidly during the past 20minutes. Walking out of the shack, past the abutment , and downto cau seway, a ma tt er of 5-6 minutes, the wat er was noticeablyr ising. Secur ed Bn. C.O. permission to pull equipment . Equip-ment was evacua ted in 20 minutes and water was more tha n 24”

deep in low points on near-shore causeway and flowing (washing)rapidly. (Figure 67) At 1210 wat er was a t elev. 16.7’ MSL as

judged by eye from bluff looking at pile cut at elev. 18. Water ha sdropped about 4 inches as of th is hour . Work cont inues on a but -ment , steel, batch plan t, and drainage of ar ea. Area is sea of mud.

22 March 1953; 1615 hrs.River over causeway [on] near shore, ranging today from elev. ,+

14.5 to 16.0. Clobdy and misty at t his hour . Steel in E abutmentand forms near ly ready [but ] lack tie wire [for t h e steel] an dbolting [to fix]&ng walls [firmly in position], plus lots of clean up.Ditching main a rea road. Lowered both cabins 7 and 8 t o d a y *

Roads very bad.





APPENDIX D 125

360’ of footbridge con- /

s t r u t t e d yesterday for usewhen needed from pier 6 to far

shore.Sta rt ed filling n ear -shorecauseway with clay from top-side, th is P.M. Drilling to blastrip rap on bluff sout h of bridge.Rip rap to be on causeway.

Mar ines closed roads a nddelayed work yesterday andday before.

25 March 1953Rained again last night and

road between bivouac area andX-Ray is impa ssable again.

Placed concrete in E abu t -ment and wing walls last n ight ,finishing at 0100 hr s. today.(Figure 68) Used navy cube4’for water w/34 E paver dis-

Figure 69. Completed piers 7and 8 in late March 1953. Thesupports seen under the middle

stiffener and the cap stayed inplace at least 14 days.

charging into 2 yd. bucket hoisted by 1% yd. P&H.

Curing cabins on piers 7 and 8 ar e disassembled and H-beambot tom-fra me r ema ins t o come out . (Figure 69)

Set H-beam cap support for plat form t o launch steel on pier8yesterda y P.M. Riveting and diaphra gming cont inues on a two-

shift basis. Additiona l welding machines received past thr ee daysbring us to five on far-shore steel. More cutting torches receivedyesterday and when more oxygen gauges are received we will bein good shape on welding rigs but can pr ofita bly use more ar cwelders. Moved nine civilian welders from B Compa ny to X-Rayyesterday to take advan ta ge of new rigs.

Wat er level yesterday and t oday is at a mean of 12.5’ MSL.Very lit t le sand in san d bar available. Two 94 yd. drag bucketspulling from upst ream side of near-shore causeway an d ma king

money.34 E plat form disassembled yesterday and will be re-erected

today. Mucking out began yesterda y in #1 pier.




27 March 1953,0755 hrs.

Visitors t oday and yesterday. Lt. Col. [Willard D.] Arnold, 8thArm y Engr. Sect., ar rived 26 March, 1400 hr s., an d depar tedabout 2130 hrs . Maj. Zwick, 417th Eng[inee]r [Aviation] Brigade,is visiting to report on bedrock and possible scour action a t bottomof piers. -

l Pu mp t rouble is our big problem. Ear ly on 25 Mar ch a bout0800 we were dewat ered in pier 1 and bedrock was sh owing indownstr eam end. Wat er broke un der t wo piles near center of E

wall an d forced removal of men and equipment . All effor ts t odewater since have failed. Water was brought to within two feet of bott om the afternoon of 25 March and sa nd r emoved in upstr eamend, but a t least 12” of sand r emains tha t washed in under th epiles. This morning the 2100 GPM is not opera tional and the 1000GPM is producing less than 300 GPM. We will shu t down pumpand again hammer a ll piles in an a tt empt t o close entr y of water.

Pumpcrete and 34 E platform are in place. Causeway is about

elev. 16 to within 20 ft. of pier 3. Dra gline (lV2 yd.) excavat ingcauseway on far shore.

27 March 1953Col. Beggs visited job and after inspecting hole pier 1, observ-

ing water coming in near boulder in NE corner , ordered diverssent up by Gp. to ar rive tonight. Plan is to muck out , one of us t oinspect hole after mucking, and t hen pour concrete ar ound edges

and over boulder. Dewater, cut out center of bottom to bedrock,and fill with concrete.

Gp. C.O. approved curb form and r ail posts to set on slab, slabto be screeded 25’ width , cor rugat ed deck to r ide up ” on topflange splice plat es. Method of placing slab t o be by pumpcretespotted near center of bridge and place W side first. Will shoot for242’ a day with curb to follow next day.

Pumps moving to pier 2. Chuseway is out to pier 3, and we are

hauling clay for fill up to elev. 12 .

29 March 1953,1700-hrs.

Visited at 1300 hrs. today by Col. Rumaggi and COL

[Ellsworth B.] Downing, 8th Army Engr. and Asst . Pleased withprogress and plans for fut ur e opera tions.

COL Beggs came up yesterday and is push ing divers a ndwork



APPENDIX D 127

Figure 70 . View of the footbr idge tha t ena bled the pum pcre te ma chine topump concrete from its location near pier 3, at center , to pier 6 across theriver channel.

on #1 and #2 . Divers made good progress t oday removing sandan d r epor t 1’ sand on upst ream end [of pier l] remaining.

Gp. C.O. ur ged pour ing of B a nd C pour s, pier 6, via footbr idge.B pour forms being set now a nd sca ffolding ha lf completed.Weather is smiling on us for a chan ge.

Causeway extended barely past #3 .Rigging going up on pier 7 for launching and Manitowoc on

last legs.

1 April 1953, 1745 hrs.Clear th is morning an d cloudy th is after noon. Placed cap

around edges of pier 1 yesterday P.M. up to bottom whaler. Diversays concrete is covering bottom and soft this P.M. Maj. Cart erdived in shallow water su it t o inspect bott om before placing inpier 1. Found edges 18” from sides and 36” from en ds clean t obedrock. Sand heaped in center area.

Divers excavating in pier 2.Placing B pour , pier 6, now using footbridge to span river.

(Figure 70)Dragline between 6 and 7 has cha nn el to san d bott om. Still




Figure 71. Downst ream girderlaunched from the west abut-ment across pier 8 to pier 7 on 6

April 1953. The 30-foot launch-ing nose extends beyond pier 7.

working, causeway is well pastpier 3.

Second ba tch of 56 gua rd-rail posts pulled today andfound well faced. New 1000GPM pump delivered da y be-fore yesterday will help. Nocritical shortages, compara-t ively speaking.

Rigging for la unching 7 -Wspan progressing. Hope tolau nch n ext Monday, 6 Apr il.

5 April 1953Yesterday divers completed

clean ing bot tom of pier 2 andremoved all loose rotten bed-rock from surface. 4’ cap placedwith pumpcrete successfully.Will dewater a t m idnight to-night , dr ill 4’ hole in bedrock,an d then complete A pour .

Pier 6, C pour this morning using footbridge.Pier 1 cap excavat ed and sand previously piled in center by

divers r emoved. Will pour today remainder of A pour in #l.Rigging for launching downst ream girder (2 beams) on far

shore being completed today.Dry weather is helping us get back to motor p a r k . 4 8

7 April 1953Placed A pour, pier 1, on Sunday successfully and on 6 Apr il

placed pier 2, A pour.Excavat ion nea r bottom on pier 3 a nd all piles down except

NW corn er and a djacent piles.Began dr iving piling #4 last night .Causeway barely past #4.

Launched downstream girder from W to 7 yesterday. No trou-ble; #8 moved 1” with greatest movement occur ring just beforenose hit #7 . #7 moved 3/# ma ximu m. Both piers a lways cam eback into position. (Figure 71)






Launch Steel:

E-2 - 20 May

E-4 - 1 JuneE-5 - 10 J u n eW-6 - 20 MayW-5.- 15 Ju n e

Finish Deck:

E-5 -

20 Jun ew - 5 - 27 J une

Present status: VV-7 downstream girder jacked to with in 1’ of plates [th at laun ching r ollers rest on]. W-7 upstr eam will befinished on 15 April an d th en launched. Seven st icks [ofl longsteel being fabricat ed on near shore. B Company 90% effective asof today.

Pier 1, C pour , today.Pier 2, B pour , complete, an d forms for C pour going in.Pier 3 piles pulled W half and all reset except three this A.M.Pier 4 piles a vera ge 4' off rock.Causeway ha lf way out to #5 .Footbridge moved upst ream between 5 and 6 to offset r apid

current.Chann els between 7-8 an d 6-7 ar e in.Beads in dr y condition and m otor pool now in use. Bear of

equipment shop still soft and impassable.Gen. Tansey, G-4 D/A:* to visit t oday. Everyone h itt ing the

ball and making money.East approach road fill going in when pans not used on cause-

way or sand haul.

16 Ap ri l 1953

Job progressing. Scaffolding on pier 1 and 2 is up, and steelgoing in for D pour. @Ygure 72) High t ide is holding up E pour on#6 .

Pfc. James E . O’Gra dy, DS51 to B Company from 74th En gr.Combat Bn., was drowned this morning at 0827 hr s. when a boatwith Lt. B a dm a n and five men capsized in the channel between

#6 and #7. Boat line t o upstr eam cable gave way a llowing boat to 2drift against a downstream cable and turn over. O’Grady dived into help a Korean civilian welder that was caught in a rope. Swiftcur rent car ried him downstr eam, and boat was 150 yds. approx-imately away from him when last seen above water . Gra ppling



APPENDIX D

un successful at 1500 hr s. fromutility boat.53

Driving penetration to rock

on #3 is slow. All piles to rock (no go) but another shift re-quired to get penetr at ion. Willlaun ch far shore th ree beamsFr iday P.M. or Sa t. dependingon wind conditions.

21 April 1953, 0900 hrs.Job progressing and the

most difficulty is on caisson #3and short 15 piles for #5.

Ordered 35 sheet piles on 9April. Five of these arr ived 20April and were wrong type.Lowboys at ESP54 yesterdaywere loaded out with non-criti-cal ma ter ials, one pulled away

from sheet piles. Schedule callsfor finish ing piles, #5, on 25Apr il. This will delay us.

Figure 72. Inside pier 2 during

D pour showing the pu mpcrete

pipe at top and th e base for t he

pneum at ic vibrat or, used t o as-sure proper placement of ce-

ment, at r ight.

Pier 3 has a split pile on W side, one pile from SE corner ,ma king 300 GPM appr oxima tely. Ha ve set in a wha ler a t 12’down, have prefabbed two other wha lers un der t his one; nextlower 2” over a ll less in dim en sion a n d bott om on e 4” overa ll less indimension. Will lower these by measured cable to desired elev. as

excava t ion proceeds. Have installed second whaler in #4 anddewat ering with sump pump. (Figure 73)

Footbridge from causeway, #5, to far shore in operat ion yes-terday P.M.

Three-beam girder 7-W down one foot and jacking proceedingnicely. (Figure 74)

Poured E [pour] of #1 yesterday and will place E [pour] on #2today.

Steel fabr icat ion proceeding on near shore for th ree spa ns, 5-4, 4-3, 3-2.Reinforcing st eel prefabbing and car pent er sh op deck a nd




r’ shifts basis.

23 April 1953, 1440 hrs.

1 Clear , windy, sun ny da y.Warm this P.M. Work goingnice1 y .

Deck and curb form s beingprefabbed.

Reinforcing being prefab-bed for deck.

Figure 73. Th e 4,100-gal lon-

per-minu te pump used to d ewa -

ter cofferda m 4 s o tha t th e lower

wha ler could be inst alled.

Spans 5-4,4-3,3-2 ar e inprocess of riveting and dia-phr agming. Have finished 16splices, four diaph ragms X,55

and five sets of stiffeners onnear shore . Setting bear ingplates on #1 and cur ing #1, #2 ,and #6 .

# 3, divers ar e cleaning bot-tom of hole.#4 has thr ee wha lers in position and four th is now being set

below the lower one. 1000 GPM pu mp is keeping water downabout 24’ from top. More clam work required when next whaler isset in.

#5 , piles a re down to within 10 ft. of rock, going O.K.Thr ee-beam girder , far shore, jacked down t o within 30”.

Pumpcrete set-up going in on far shore. Approach roads W side[are] to grade most places. Base and finish course for a pproachroads t o be crushed from local cliff basalt.

25 April 1953, 0925 hrs.Gp. C.O. visited job yesterday and ordered a bulkhead pu t in

#3 about 3’ from downstream end to hold concrete up 15’ to sealoff split piles. Remainder of bottom t o get a 3’-4’ cap when clean .Divers finished cleaning bottom yesterday P.M. This A.M. statusis five piles hooked together with 12” H-beams resting on bottom,th ree whalers preventing pile movement upst ream when filledwith concrete. Timber laps or panels will cover space betweenpiles and edges of caisson.



APPENDIX D

#4, high pile in SE corn erallowed [to] cave in yesterdayP.M. and pile r ig moved overfrom #5 and r edriven. Excava-t ion by clam this A.M. proceed-ing n icely. Steel on fa r shore7-W is about 14” from cap.

Two 2100 GPM pum ps ar -rived yesterday.

26 April 1953, 1500 hrs.

Placed concrete blanket in#3 th is A.M. and [it is] up 20’on downst rea m side. Blowoutin NE corner of #4 about 1500hrs. Hole now has 3%‘-4%san d upstr eam end. Pr ior toblowout sa nd was 8 ” upstreama n d 20”_22” downstream.

Tapped down pile, still in pr o-gress.

Figure 74. View sh owing crib-bing used in launching up-

stream girder from the west

abutment to pier 7.

#5 , second wha ler going in now.#4 ha s 4100 GPM of pumps ma king full pipe.Weather fme. All other work cont inu ing.

29 April 1953, 1800 hrs.J ust completed A pour on pier 3. Will pump down #4 after

midnight, clean up blanket cap, and place A pour on #4 tomorrow.Rain yesterday, last night and all today a slow rain. River not

affected a s yet . Watching closely. Night sh ift advised of pre-cau t iona ry measu res t o ta ke in a nt icipat ion of possible highwater .

#5, bottom (4th ) whaler is hanging and clam is clean ing out .Pile on SW corner will not budge. Hole making about 2500 GPMwith lots of aggregate coming under SW corner. Will muck outwith divers.

Lack about two days r iveting on near shore 3 spans, and oneday more diaphragming on span 7-W. Deck going on downstreamof 7-w.

J ob on schedu le to finish 27 J un e. A flood will hu r t us bad.




1 May 1953,091O hrs. (Map 4)J ob sta tu s as of th is hour :Piers 1, 2, 6, 7, an d 8 complete.Pier 3, pour A complete, B pour forms a nd steel ready for

concrete when A pour has set.Pier 4, a blanket placed 3%’and another pour averaging 15’

completed. Will finish A pour on 1 or 2 May.Pier 5, expect t o complete m ucking and pour blanket 5 -6

th ick th is dat e.Causeway complete.Abutment s complete, except E abut ment requires st ep after

steel is lau nched.

East and west approach roads, sub-grade complete except 400’on E where st eel fabr icat ion is accomplished.

Steel 7 -W laun ched and n ear ly sub-decked.Spans from 5-2 will be riveted on near shore today or tomor-

row. Diaphragming underway.

3 May 1953,182O hrs.J ust finished A pour of pier 5. The las t one. Oh Happy Day!

7 May 1953H ave com pleted C pour , pier 3 a nd 4, an d B pour, pier 5. Three

spa ns of s teel on n ear shore nea rly ready for lau nching on 12 Ma y.Decking on upstream will be finished tomorrow and downstreamto follow. [Launching] Boilers ar e in p lace on pier 1 an d 2 andr igging going in now.

Deck on 7-W is rea dy for concrete a t 0500 hr s. tomorrow.Army issued a lot of changes via t elephone from Gp. C.O. las tnight but resolved today. Cont ra ry to previous agreement we will.pour monolithic from 7 t o 8 to W abut ment .

F orm s r eady on pier 3, D pour . Work ing tonight on D of 4 an d Cof5.

Crusher broke gears last night for second time.Pontoon bridge going in before Sunday will hinder opera tions I

of concrete work. Asked for 2MPs near shore to give us pr iority.

8 May 1953Deck slab 7-W placed between 0720 hr s. and 1520 hr s. th is

da te. Cra cks occur red between 7-8 an d 35-40 feet west of 8.Cra cks ar e deep an d occur more or less diagona lly.



Battlefrontin Western Korea

1 May1953

1 10 km. J

NII

12FE

.Tongduchon-ni

X l XT1 CofnmonweatthXRoKx

I

1lUijongbu

12T E

MAP 4

I




Figure 75. Troops laying the concrete deck.%o steel mats reinforced the

concrete to provide an “antiartillery” safety factor beyond the necessary

load-carrying strength. The concrete placing was monolithic andontin-

Mix was 8:12:20. Concrete well vibra ted and well placed,ta mped, and screeded. Sun was hot after 1400 hr s. but not whencracks appear ed at 1300 hr s. No cra cks observed nearest abut -ment. My belief cracks were due to movement caused by reverseloading span 8 -W with concrete. Wind was 15-25 MPH. Concreteis under san d bags and/or canvas and sa nd. Moist.

11 May 1953 ,163O hrs.

Rain, a dr izzle yesterday and th is morning heavier. This P.M.rain was har d un til 1600 hr s. Bn. C.O. ordered evacua tion of allequipment from cau seway about 1300 hr s. Evacua tion completeexcept final removal of footbridge.

Pier 5 ready for concret e D pour.Pier 3 and 4 lack E pour forms which ar e on scaffold but not in

place. Schedule calls for D of 5 today and E of 3 and 4 tomorr ow.Curb u pstr eam placed th is morn ing, and a bout 93 of down-stream , span 7-W. Rain pr events proper fmishing.



APPENDIX D 13 7

12 May 1953,1730 hmRains of two firevious days hit us a t 0915 h r s . when waterbegan to go over cau seway. All equipmen t removed. Men left

working on forms, #3 and #4 .Finished placing curb t his P.M. Spoonbill out an d X-Ray pon-

toon out. Water now at 20.4 ft., highest th is year .Launched 3-beam upst ream girder to #1 today. Lots of trouble

due to cr ibbing i i nk ing from ra ins.Unloading cement from railhead.Reinforcing pr efab and carp [sti] prefab tonight . Steel near

an d far shore will be welding.I Corps C.G.@visited job this P.M.

14 May 1953,082O hrs.River flood r eadings, MSL, follow:

Date Time Elevation12 May 1330 20.0’

12 May 1500 20.3’12 May 1600 20.4’-12 May 2100 20.4’12 May 2200 20.0’13 May 0700 19.0’13 May 0800 19.4?13 May 0900 19.6t

13 May 1000 19.Y

13 May 1100 19.0’13 May 1200 18.7 t13 May 1300 18.6t

Date Time Ekvation

13 May 1400 18.3t

13 .May 1500 18.2t13 May 1600 18.0t13 May 1730 17.gt -

14 May 0700 14.Y

Causeway showing inspots.

14 May 0800 16.BtTide coming in.

14 May 0830 17.3t -HT at 0950.

Causeway being extended pan wide5’ along rip rap upst reamout to ra mp. Men work ing on ra mp for 34 E, badly eroded. Newra mp near E abu tm ent com pleted but wa ter i s too h igh t o lay p ipe.Believe quicker to repair old ramp between pier 2 and 3.

17Mayl953 ’

Last pour of last pier completed at 2130 hours, 16 May 1953,on E pour , pier 5. D pour , pier 5, completed 0400 hr s., 15 May, and




Figure 76.“Jackson’s chariot,” which could be rolled from the deck, pro-viding scaffolding for bridge painters.

E pour of #4 and #3 dur ing the daylight of 15 May. Only 15” of form r emoved from D pour of #5.

All steel is in place for fma l fabr icat ion on both shores.Carpenter shop is building more cur b form s and deck slab

forms. Also mess tables for H&S and C Compa nies.Company C removing forms and building launching scaffolds.Company A cru shing road metal, prefabbing mats, clean ing

and repair ing pumpcrete, and policing job site. Have lots of ha nd

dressing an d rip r ap t o do on far shore appr oach.1 plat oon, C Compa ny, at Whitefront fender pile job.

22 May 1953

Misty rain th is morn ing.Four ar c welders a re a t Teal repairing bomb dam age tha t

occurred on A.M. 20 May.Jackson Chariot58 tr ansport ed to far shore yesterday and is

now in process of erection to remove catwalks a nd [to] pa intbeams. (Figure 76)

Fa r shore st eel requires two splices to complete r iveting of span 7-5. Near shore requires 27 splices to complete 2-l-E.

Founda tion for monu ment placed 21 May. Car penter shopfabr icat ing monu ment forms.






Figure 77. View showing portions of the 606-foot girders that were

launched from the east abutment to pier 5. These were the longest girdersused on the bridge.

5 June 1953Both upstream and downstream girders are jacked down.

Seven diagona l diaphragms nearest #5 are in process of welding.Sub-deck complete except for loose areas over piers and dia-phr agms. Steel beam s cut to proper length an d in position. Eabutment step forms going in. W approach slab being graded. Gp.ordered a 50’ slab of 8” reinforced concrete on W appr oach withconst[ruction] j[oin]t down center line an d expan sion jt a t 25’. Eapproach to be penetr at ion asph alt.

Fill on E a pproach near ly to grade within 100 ft. of abutment .Rock is on W approach.Catwalk complete E t o 5 up a nd downstr eam.Slab forms near ly complete upstr eam.Gett ing rea dy to lau nch 7-6-5.

9 June 1953J ob Stat us -Rain began about 0400 hrs., some 50 ft. before

deck slab 5-4-3 was finished. Concret e completed to 3 and roughscreeded, but left high near 3 expansion joint. We are reworking it





14 2 BRIDGING THE IMJ IN

16 June 1953

Last concret e completed at 2345 hrs . , 15 J une, in curb span5-6-7..

5 July 1953The &Ray project became the completed Libby Bridge yester-

day at dedicat ion ceremonies by Gen. Maxwell D. ‘kylor, Com-man ding Genera l, 8th Un ited Stat es Army, at tended by 35 star sand digni@ies. Good weather, good ceremony. Bridge opened tot ra ffic, all except t an ks, at 1200 hrs ., 4 J uly. This log is her ebyclosed. .



Notes

In t roduc t ion

*’ 1 . J ohn Miller, J r.; Owen Ca rr oll; an d Mar garet !I&kley, Korea,19514953 (Washington:Of&e of the Chief of Milita ry H istory, l956),pp. 162-110; Comm an d Report , Engineer Section, I Corps , May 1951,Narr at ive, pp. 12-13, cont ained in Box 1536, Ent ry 429, Record Group407, Records of the Adjutan t Genera l’s Of&e,National Archives, Sui t -land, Mar ylan d. (All boxes listed in t he n otes t o this In tr oduction ar e

cont ained in th e sam e record group, ent ry, and r epository.)2. Comma nd Report , Engineer Section, I Corps, J une 1951, Nar ra -

t ive, pp. 3-5, Box 1543.3. Ibid., pp. 7-10; Comma nd Report , I Corps, Nar ra tive Summ ar y,

J un e 1951, Box 1538.4. Command Report ; Engineer Section, I Corps, J une 1951, Narra -

tive, p. 10, an d Ann exes 22 an d 23, Engineer Section Da ily J our na l,22-23 J un e 1951; Comma nd Report , En gineer Section, I Corps, J uly1951, Nar ra tive, p. 3, Box 1550; Walter G. I Ie r rnes , Zkce Tent and

Fighting Front, United Stat es Army in th e ISorean War (Wash ington:

m ce of th e Chief of Milita ry Hist ory, Governmen t P rin t ing GfXice,1966), pp. 15-18.5. Comma nd Report , Engineer Section, I Corps, J uly 1951, Narra -

tive, pp. 9-12 and 15-19 with the quota t ion on page 15; Ann exes 21-25,Engineer Section Daily J our na l, 21-25 J uly 1951; and Ann ex 54, RiverGauge Readings 19 thr u 31 J uly 1951.

6. Comman d Report, En gineer Sect ion, I Corps, August 1951, Nar -ra t ive, pp. 3-9, Box 1557.

7. Comman d Report, En gineer Sect ion, I Corps, August 1951, Nar-ra tive, pp. 3-5, 8-11, 15, 16, 20, and 25-27; Comm an d Report , 84thEngineer Const ru ction Bat ta lion, August 1951, Box 5077.

8. Command Report , Engineer Section? I Corps, August 1951, Nar -ra tive, pp. 16 and 23.

9. Comm an d Report , I Corps , Septem ber 1951, Na rr at ive S u m =ma ry, pp. 10-19, Box 1559.

10. Comman d Report , Engineer Section, I Corps , September 1951,Nar ra tive, pp.. 9-10, Box 1564; Comm an d Report , 1169th En gineerComba t Group, September 1951, Nar ra tive, pp. 2-3, Box 5160.

ll Command Report , I Corps, October 1951, Nar ra tive Summar y,pp. 6-49, Box 1566. Comman d Report , Engineer Section, I Corps, O&o-h er 1951, Na rr at ive, pp. 2-4; Att achm ent 35, En gr Opn 0 131, 18October 51, it ems 3b (11) and (12); and Att achment 38, Engr Opn 0 134,28 October 51, it em 3a (2), Box 1571. Comm an d Report , En gineerSect ion, I Corps, November 1951, Att achment 38, En gineer PeriodicOperations Report 183,31 October-10 November 1951, item 3b, Box





NCYFES 145

and April 1952, Inclosure 15, Engineer Periodic Opera t ions Report 11,9-18 Apr il 1952, Box 5885; Comm an d Report , En gineer Sect ion , ICorps, April 1952, Na rra t ive, p. 5, Box 1613.

25. Comman d Report s, 62d Engineer Constr uction Bat talion, April

1952, cont aining Engineer Periodic Operat ions Report 12,19-29 April1952; May l952, cont aining En gineer Per iodic Opera tions Report sl3--l5,30 Apr il-28 May 1952; J un e 1952, cont aining Engineer PeriodicOperations &por t s 16-18,29 May-29 J un e 1952, a ll in Box 5885; andJ uly 1952, cont aining Engineer Per iodic Operat ions Report s 19-21,29June-28 J u l y 1952, Box 5886. Comm an d Repor t, E ngineer Sect ion, ICorps, July.1952, pp. 1 an d 7, Box 1633. Comman d Report , 24th En gi-neer Const ru ction Gr oup, Febru ar y 1952, Inclosur e 4.

26. Comman d Report, Engineer Section, I Corps, May 1952, Nar r a -t ive, p. 6, Box 1619; Comm an d Repor t, 84th En gineer Cons tr uction

Bat ta lion, J un e 1952, Nar ra tive, p. 1, Box 5914.27. Comma nd Report s, 84th En gineer Const ru ction Batt alion, Feb.ru ar y 1952, Narr at ive, p. 2, Box 5912, an d J uly 1952, Narr at ive, p. 1,Box 5914; Comm an d Repor ts, Engineer Sect ion , I Corps, May 1952,Narr at ive, p. 7, and J uly 1952, Narr at ive, p. 7; Comma nd Report , Engi-neer Section, Eight h Army, Mar ch 1952, Na rr a tive, p. 13.

28. Command Reports, Engineer Section, I Corps, April 1952, Nar -rat ive, Box 1613; May 1952, At ta chm ent 33, En gr Opn 0 159,13 Ma y1952, Box 1619; and J une 1952, Nar ra tive, p. 5, Box 1625. Flood Report ,1 J uly-15 September 1952, En gineer Section, I Corps, p. 2, Box 1633.

29. F lood Beport , 1 J uly-15 September 1952, Engineer Section, ICorps, pp. 2-4; Comman d Report , Engineer Sect ion, I Corps, J uly 1952,Narrative.

30. Flood Repor t , 1 J u ly-15 September 1952, En gineer Sect ion , ICorps, pp. 3+5, with t he quota tion on page 5; Comman d Report , Engi-neer Sect ion, I Corps , July 1952, Na rra t ive, p. 1.

31. Flood Repor t , 1 J u ly-15 September 1952, En gineer Sect ion , ICorps, pp. 1 and 6.

32. Comman d Report s, Engineer Section, I Corps, September 1952,Na rr at ive, pp. 4-5, Box 1645, an d October 1952, Narrat ive, p. 3, Box1651.

C on s t r u c t ion o f L ib b y a n d T e a l Br id g e s , Im j inRiver , October 1952 t o J u ly 1953

P r e f a c e

1. As-Built P lans of the Libby Bridge, prepared on 3 J uly 1953, arecont ained in t he P aper s of William C. Cart er, J r., Office of History,Headquart ers, U.S. Army Corps of En gineers, Kingman Building, FortBelvoir, Virginia, and at Tab 11 of the t ypescr ipt vers ion of this st udycont ained in file 8-5. lA/DK,Hist or ica l Resour ces Bra nch, U.S. Arm y




Center of Military History, Wash ington, D.C. A photocopy of the type-script study, less !Ihb 11, is contained in file XII-7-9, Milita ry Files ,m ce of History, Headqua rt ers, U.S. Arm y Corps of Engineers.

Ch a p t e r I

1, Engimhing Report on Br idge Stu dy an d Design, Teal Site,Imjin River, 2d En gineer Const ru ction Group, 14 September 1952,prin ted at Appendix B below.

2.&se

Ibid. .This is the official opinion based on s t ud i e smado by J a p a -an d Korean engi?eers .Major William C. Car ter , S-3,84th Engi -

neer Constr uction Bathl ion , found evidence indicat ing that th is was nottru e of the Libby bridge site. See the interview of Major Car t& by MajorWilliam R. Farquhar, J r., 5 and 20 J uly 1953, a copy of which is att achedto the original stu dy at n b 2. Japan ese officials ent ered Korea afterth eir na tion’s victory in the Russo-J apanese War, and J apa n form allyan nexed Korea in 1910. It r etained cont rol of th e peninsula unt il itssur render a t t he end of World War II.

3. Letter , Headqua rt ers, 2d Engineer Const ru ction Gr oup, 20August 1952, subject: Pr elimina ry Ana lysis of Dan ger t o Zmjin RiverBridges Durin g th e Flood .of 30 July 1952.

4. Eight h Army St&Study, Imjin River Br idges,24

&ptembe r1952, prin ted in Appendix A below.5. Flood Report , 1 J uly-15 September 1952, Engineer Section, I

corps, p. 1. ..

6. Ibid., p. 3.7. Ibid., p. 4.8. Ibid., p. 6.9. Major Genera l (later Lieutenan t Genera l) Pa ul W. Ketidall corn-

manded I Corps, an d General J am es A. Van Fleet comman ded Eight hArmy.

10. Brig. Gen. J ohn K. Wat ers , Chief of Sm , I Corps, t o Command-

ing Genera l, Eight h Army, 2 August 1952; 1st Indorsement of aboveletter, Comma nder , Eight h Army, to Comma nder , I Corps , 11 August1952; an d Water s to Com m an ding Gener al , Eighth Army, 14 September1952, all prin ted in Appendix A below.

11. Colonel William C. Baker , J r., was Eighth Army En gineer .12. The 2d.Engineer Cons tr uction Group, comm an ded by Colonel

Henry J . Kelly, was a t t a c h 4 to Eight h Arm y.13. ColotielMerrow E. Sorley was I Corps En gineer .14. Eight h Army Sta ff Stu dy, Imjin River Br idges, 24 September

1952, and Lt . Cal. C. W. Bur leson, Assistan t Adjutan t General, Eight h

Arm y, to Comm an der, I Corps, 29 September 1952, both pr int ed inAppendix A below.

15* En gineer ing Report on Br idge Stu dy and Design, Teal Site,hj in River, 2d Engineer Cons tr uction Group, 14 September 1952;Eighth Army St&Study, Imjin River Bridges, 24 September 1952; an dBur leson t o Comm an der, I Corps , 29 September 1952.







NWI'ES 149

5. A copy of Opera t ions Order 840376,2d En gineer Const ru ctionGroup, 25 October 1952, is at Inclosur e 5 of the group’s Comman d Report

for October 1952, cont ain ed in Box 6001, En tr y 429, Record Grovp 407,&cords of the Adjutan t Gen era l’s Of&e,Nat iona l Archives, Suitlan d,Mary landa

6. Ea ch pile was a 16-inch diameter pipe ma nu factur ed by th eArmco Steel Compa ny.

7.*’ A cross-section of th e pier column indicated on the bridge plans.8. Major Dan iel 0. Stoudemire.9. No tem plat e was actually used to drive th e sheet piling.10. Major William C. Car ter , J r., S-3,84th Engineer Const ru ction

Bat talion, joined the unit on 22 November 1952.

11. Lieutenan t Colonel Howard K. Eggleston, J r., Execut ive mcer,2d En gineer Const ru ction Group.

12 . The concrete cur ing cabins used on t he Libby Bridge piers werenamed for t he enlisted man in the 84th Engineer Const ruction Bat ta lionwho developed t hem.

13. Group Equ ipment Pr i c e r .14 . Seoul Mun icipa l Airfield.15.Yokohama En gineer Depot..16. Before sheet piling could be su nk , it had to be covered with a

female-shaped sheet pile head, and an ada pter had to be at ta ched to the

pile driver.17. The &cubic-yard pan range of the plant was th e area around it inwhich a D7 Cat erpillar tr actor pu lling a t ra iler of th at capa city couldprofita bly opera te.

18. Willard Norr is had just been pr omoted to lieutenant colonel. Hewould leave the 2d Engineer Constr uction Group in late December 1952to assum e comman d of th e 76th E ngineer Const ru ction Batt alion a tYongdungp’o, near Seoul .

1% Eight-and-a-half percent of the a ggregat e was fine enough topass t hrough a nu mber 80 screen.

20. Fifteen feet above mean sea level.

21. A 2,lOO~gallon=per-minute pump.22. Stat ion 12 + 51 refers t o a locat ion 1,251 feet west of the center of

th e bridge, or some 200 fm t beyond t he west abut ment.23. First Lieutena nt Melford Dameron , J r., is identified in a mem -

ora ndu m sen t by Colonel Raymond Beggs, comman der of th e 2d Engi-neer Constr uction Group, to Brigadier Genera l Frank Bowman, Engi-neer, Arm y Forces in t he Fa r Ea st, on 22 October 1953, as one of th eofficers in the group headqua rt ers who should receive proper recogni-tion for his r ole in designing an d const ru cting Libby bridge. This mem-ora ndu m is in the Papers of Ran k Ott o Bowman , Hoover Inst itut ion,

Stan ford, Californ ia. A “Lt . Damron” appear s occasiona lly in th e dailysm jour na ls of th e group cont ained in Boxes 60006004, En tr y 429,Record Group 407, Nat iona l Archives, Suitlan d, Marylan d, an d MajorCart er sometimes spells the name that way subsequent ly in the log, butth ese appar ently refer to th e sam e Melford Dameron , J r .



.

150 BR IDG ING THE IMJ IN

24* The clutch on a 500.cubic-foot-per-minute-capaci ty air com-pressor.

25. A stea m-opera ted aspha lt bat h un it capa ble of hea ting up toth ree railway tank cars of aspha lt.

26. At th is t ime Colonel Raymond Beggs was th e commander of the2d En gineer Const ru ction Gr oup, . and Lieutena nt Colonel J am es R.O’Grady comman ded the 84th En gineer Const ru ction Bat ta lion.

27. An interna l bracing made from a ten-inch H-beam.28. Four feet a bove mean sea level.29. A concret e composed of a r a tio of one par t cemen t , two par ts

coarse a ggregate, and t hr ee parts sand.30. D7 Caterpillar tr actors.31. Colonel Henry J . Kelly, who ha d comman ded th e 2d Engineer

Constr uction Group, became Opera t ions mcer , S-3, Engineer Section,Eighth Arm y, on 8 December 1952. He replaced Lieutena nt ColonelWilliam H imes in th at position.

32. Lieut enant Colonel Edward J . Ribbs.33. KATUSA Corpora l Kim Ho Duk.34. Brigadier Genera l Fra nk 0. Bowman , Engineer, Army Forces in

the Far East.35. Flat bed tra iler.36. The paver was a ble to park on th e bulkhead right above th e

hopper on th e pumpcrete.37. On 10 Februar y Compa ny B, 84th Engineer Const ru ction Bat-

- ta lion, moved from the Teal bridge site to Tbngduchon-ni, a t own some12 miles east of the X-Ray bridge site, to const ru ct living an d operat ingfacilities for th e 78th En gineer Field Maintenan ce Compa ny.

38. Teeth built f l ush .aga ins t th e inside of the dr ill.39. A bucking tool, or bucker , was used to form a backstop for a rivet

gu n40. Lieuten an t Colonel J ohn R. Pa rker was in t he 32d Engineer

Const ru ction Group st at ioned a t Wonju, Korea , and he became its corn-

mander on 13 Mar ch 1953. The 34th Engineer Group was stat ioned atCamp Robert s, Californ ia, in t his per iod.

41. Failing was a brand na me.42. The Yawata Steel Compa ny zwas a J apanese manufactur er.43. Insta lling cross bra ces t o fom girders. . -

44. In a ddition to the horizont al middle st iffener , C pour inchided alow pedesta l, rising a short height above the st iffener , on each .of the

vertical legs of th e pier. The pedestal on t he downst ream column of pier 7.

was removed with-jackhammers due to . b a d concret e product ion.45. Tides at Inch’on were derived from a published t ide table and

th en compa red with observed tides at th e X-Ray site.46. First Lieut enan t J ames J . Scott , J r.47. A large steel box. .. :

48. The motor par k h ad for a per iod been mired in mud.49. Major Keith E. Eiler was chief-of th e Plan s an d Requirements

Bra nch, Engineer Section, Eight h Army. .



NC YI ’ES 151

50. Major Genera l Pat rick Henry !&msey, a career engineer officer,was outgoing chief of the Supply Division, OfIice of the Assista nt Chief of Staff, G-4, Gener al Staff, U.S. Arm y.

51. Detached service.52. First Lieut enan t Cur tis W. Badman was a platoon leader in

Compa ny B, 84th Engineer Const ru ction Bat ta lion.53. Private O’Grady’s body was r ecovered on 22 April 1953.$4. En gineer supply point .55. Cross diaphra gms.56. Major Genera l Bruce C. Clarke.57. Roughly one lan e in width .

. 58. This movable scaffold was named a fter th e mainten an ce officer

of th e 84th En gineer Const ru ction Bat ta lion, War ra nt Pr i c e r PeterJ ackson, who designed it.

59. The receipt of ten oxyacetylene torches ena bled the ba tt alion toretur n t he t orches it h ad borr owed under Memos of Receipt from otherunits.

. !

60. Chinese shelling of I Corps defensive positions nea r t he X-Raysite increased beginning on 25 May as th e enemy prepared for groundassaults on 28-29 May tha t net ted it Outposts Carson, Elko, and Vegas.These outposts were locat ed about four miles northwest of th e X-Ray siteat op h ills forward of I Corps’ ma in line of resistan ce.

61. The enemy roun d .exploded near an emplacement of four .50-caliber machine guns ma nned by the 21st Antiaircra ft Artillery Batt al-ion, an element of the 25th Infantr y Division. This division had r elievedth e 1st Marine Division on th e western flank of the I Corps front on 5May 1953.

.

62. Headquar ter s, Division Art illery, 25th Infan tr y Division.63. The last minu te cut-out s would r eplace bad r ivets.64. Colonel Hoy D. Davis, J r., was a n E ngineer offfcer serving at

Headqua rt ers, Eight h Army.65. The visitors from the Army of th e Bepublic of Korea were Briga-

dier Genera l Min Byong Kwon, th e Adjutan t Gener al, and Br igadierGenera l Urn H ong Sub, the Chief En gineer.






Fig.

31 .

32 .

33 .

34 .

35 .

l 36 .

37 .

38 .

39 .

40 .

41 .

42 .

43 .

44 .

45 .

46 .

47 .

48 .

49 .

50 . .

51 .52 .

53 .

54 .

55 .

56 .

57 .

58 .

59 .

60 .

61 .

62 .

63 .

64 .

65 .

66 .

67 .

68 .

69 l

l &L 70 .

71 .

Ibid., figur e 16.Ibid., figur e 17.Command Report , 2d Engine.er Const ruction Group, J anuary 1953,Nationa l Archives Record Group 407.“Const ru ction of Libby an d !I’!eal Bridges,” figure 18.Ibid., figure 19.Ibid., figur e 20.Ibid., figur e 21.Ibid., figure 22.Ibid., figur e.25.Ibid., figur e 26.Ibid., figur e 27.Ibid., figure 28.Ibid., figur e 32.Ibid., figur e 33.Ibid., figur e 35.Ibid., figur e 38.Ibid., figur e 34.

lIbid., figure 40.Ibid., figur e 41.Ibid., figur e 42.

Ibid., figur e 44.Ibid., figure 43.Ibid., figure 45.Ibid., figur e 48.Ibid., f&we 49.Ibid., figure 50.Ibid., figure 52.Ibid., figur e 53.Ibid., figure 54.Ph otograph SC 431293, DSMRC.

Pa pers of William Clarence Car ter , J r., photo 20, Ofke of History,Headquart ers, U.S. m y Corps of En gineers.Papers of William Clarence Cart er, J r., photo 25,Of&e of History,Headquart ers, U.S. Arm y Corps of Engineers.Photograph SC 435746, DSMRC.Slide Collect ion, Bok 46, Slide 1-16, C&e of History, Headqu ar -t ers, U.S. Arm y Corps of Engineers.“Cons tr uct ion of Libby an d ‘Ikal Bridges,” figure 24.Ibid., figur e 30.Ibid., figure 31.

Comman d Report , 84th E ngineer Const ru ction Bat ta lion, March1953, Nat iona l A&hives Record Group 407. Z’

Ibid.‘Cons tr uct ion of Libby and Tea l Bridges,” figure 36.Comman d Report , 84th En gineer Constr uction Bat ta lion,- April1953, Nat iona l Archives Record Group 407. .

*-



PHCY IO S O U R C E S 155

Fig .

72 .

73 .

74 .

75 .

76 .

f 77 .

“Construction of

Ibid., figur e 29.

Libby and Tea l Bridges,” figure 37.

Comman d Report , 84th En gineer Const ru ction Batt alion, April1953, Nat iona l Archives Fiord GrouD 407.Y!onstruction of Libby and Tea l Bridies ,” figure 51.Ibid., figure 55.Ibid., figure 46.




Combat Forces Pr ess, 1955) includes considerable d iscussion of engineer opera tions du ring th e Korean War , some relat ing tobridge building, in a compilation of brief accounts of Army work behind th e front lines. The Milita ry Engineer pu blished, in1951-1958, ar t icles by Army Engineer officers on br idges builtdur ing th e Korea n War over t he Imj in (47: 116-118 an d 50:

1140115), th e Han (47: 333-336 an d 48: 2810284), th e Nakt ong(43: 96-lOO), the Pukhan (44: 86087), and the Twinnan (44:43-45) rivers a nd on ra ilroad bridges in Korea (43: 332-333 and47: 333-336) .

.

While rivers h ave formed significan t m ilitar y bar r iers an dmilitar y bridge building has played an import an t pa rt in warfaresince ancient t imes, no survey of this t opic ha s been published inEn glish since 1853. Bridge-building effort s a re regular ly dis-cussed in accuunts of specific war s and campaigns, however. Anumber of books discuss militar y bridging during World War II.The official hist ory by Alfred M. Beck et a l., The COTS ofEngi-neers: The War Against Germany, U.S. Army in World War II(Washington: U.S. Army Center of Military History, Government

’ Pr int ing Office, 1985), tr eat s U.S. Army bridge-building work in-Europe dur ing tha t war in considerable deta il. The most massiveAmer ican bridge-building effort of the war , made on th e RhineRiver, is the subject of special reports by Fir st , Third, Sevent h,and Ninth Armies; XVI Corps; and th e 1110th Engineer .Comba t .

Group, but th ese report s a re genera lly available only in spe-cialized collect ions on engineer opera tions a nd milita ry history,such as th ose of the Office of History of the Corps of En gineers.

Somewhat more widely available is the r eport by the 12th ArmyGroup’s engineer P a tr ick H . Timoth y, The Rhine Crossing:lluelfth Army Gioup Engineer Operations (Fort Belvoir: EngineerSchool, 1946). A publication by the Brit ish Corps of Royal Engi-neers, Bridging Normandy to Berlin (n.p., 1945?), describes th ebridge-building efforts of Field Marshal Sir Berna rd Mont gom-ery’s 21 Arm y Group. Engineer History, Mediterranean Theater,

Fifth Army, 3 ~01s. (n.p., J945?), contain s det a iled discussions of bridge const ruction in It aly amid report s of other engineer opera-

t ions ther e. U.S. Army bridge building in Asia and the Pacific isdiscussed in Karl C. Dad , The Corps of Engineers: The War

Against Japn, U.S. Arm y in Wor ld War I I (Wash ington: U.S.Army Center of Milita ry History, Governm ent P rin ting OfTice ,

1966).

,’

l -



Suggest ions for F h t h e r l3eading

The efforts of U.S. Army engineers to build durable bridges,across th e Bqjin River form both an episode in th e history of milita ry bridge building and a litt le un derst ood aspect of the *

Korean War. Readers of this volume may want to pursue further .- reading in either or both of those subject a reas.

The r ecent ly published book by Bevin Alexander , Korea: The First War We Lost (New York: Hippocrene, 1986), provides asuperb overview of the milita ry a nd diploma tic event s of th eKorean War , together with th ought ful insights in to its politicalcontext. Walter Hermes’ Z%uce Tent and Fighting Front, U.S.Army in the Korean War (Washington: U.S. Army Center of Military History, Government PrintingOf&e, 1966), concen-

tr at es on U.S. Army opera tions during the last two year s of th e-war , along with their diploma tic cont ext, while Pa t Meid’s andJ ames Yingling’s Ope r a t& s in West Korea, U.S. Mar ine Opera -tions in Korea , 1950-1953, vol. 5 (Wash ington: Mar ine CorpsHistorical Division, Government Pr int ing OfXice, 1972), discusses $

Marine operations near the Imjin River. Matthew B. Ridgway’sThe Korean War (Gar den City, NY: Doubleday, 1967) and Mark W. Clark's fiom#ze Danube to the YaZu (New York: Harper, 1954)cont a in t he m emoirs of th e successive Un ited Na t ions corn-

manders during the last years of the war .More detailed opera t iona l accoun ts of the fight ing near t he

Imjin River are provided by Cyril Barclay’s The First Common-wealth Divisibn: The Stop of British Commoruuealth Land Forcesin Korea (Aldershot , En glan d: Gale a nd Polden, 1954) an d The

First Team: The First Caualry Division in Korea, 18 July 195048 January 1952 (Atlan ta: Albert Love, 1952). Lively accounts of Korean War combat told from the van ta ge point of the ordinar y

soldier ar e cont ained in a book by T.R. Fehrenbach, This Kind of War: A Study in Unp&pbe&ess (New York : Macmillan , 1963),and in two works by one of the most popular military historians of the period, S.L.A. Marshall, The River and the Gauntlet (NewYork: Morrow, 1953) and Pork Chop Hill: The American FightingIMan in Action, Korea, Spring, 1953 (New York: Morrow, 1956).

John Ge Westover’s Combat Support in Korea (Washington:



SUGGESTIONS FOR FURTHER READING 159

Prior t o World War II, British engineers au thored many of the

leading English-lan guage works on military br idge building. In1816 Ma jor Gen era l Sir H owa rd Douglas pu blished one of th e firstworks on th is subject, An Essay on the Principles and Constructionof Military Bridges, and the Passage of Rivers in Military Opra-

tions. The book was so popular. tha t Douglas subst an tia lly ex-

panded it, and later edit ions appear ed in 1832 and 1853. The book

discusses many bridging opera tions in eighteent h and ear ly nine-teenth century warfare, and each edition includes more recentconflicts. The Work of the Royal Engineers in the European War,

1914-19, vol. 1, Bridging (Cha th am: Royal Engineers’ Inst itu te,1921), provides a detailed report on British bridging operations inWorld War I.

The American Civil War witnessed some very significan tbridging operat ions. They are described in a long article by Corpsofficers Michael McDonough an d Paul Bond, “Use a nd Develop-ment of th e Ponton Equipage in th e United Sta tes Army, withSpecial Reference to the .Civil War,” Professional MeFirs, Corps of Engineers, United States Army, and Engineer Deprtment at

Large .6 (1914): 692-758. Bridging was less importa nt to Amer i-can opera tions in fian ce dur ing World War I, but U.S. forces did- -7build sever-al significant bridges across the Aire and MeuseRiver&war d th e end of tha t war . This bridge-building work isdiscussed br iefly in Historical Report of the Chief Engineer, In-eluding. all Operations of the Engineer Demrtment, American

Expeditionary Forces, 1917-1919 (Wash ington: War Department ,1919), prima rily on pages 210.226. W.R. Inga l l s , ed., History of

the 27th Engineers, U.S.A., 1917-1919 (New York, 1920), pro-

vides a det ailed accoun t of th e work of a un it t ha t served as abridge regiment dur ing the MeuseArgonne campaign.





Index*

A-R-West , Maj. Gen %M . M. SeeWest, Maj. Gen: M. M. A-R-.

Abutments : 35, 46-47, 50, 68, 107,‘&109, 110, 112, 117, 118, 122,123,124, 125, 133, 134, 136,137, 140

Aggregate: 50, 98, 102, 104-105,106,107, 113, 118, 133, 149

Aggregate dryers: 52., 100, 102,103, 105, 106, 107, 119

Aggregat e plan ts: 100, 103, 104,105, 106bat ch bins: 106, 122elevators: 104heat ing plants: 100loader-conveyors: 105shower unit s: 52, 100, 109

Air compressors: 108, 150Allen, Lt . Col. Glenn J .: 119, 120Alluvium:96-97

Anchor bolts: 39, 46Anchor piles. See Piles, anchor.Anderson, Maj. Edward G., J r.: 93,

148Angle iron: 110, 113Ant iaircra ft Art illery Bat ta lion,

21st:139, 151Approach r oads: 6, 10, 35, 36, 98,

100, 104, 107, 110, 116, 117,118, 119, 120, 121, 130, 132,134, 137, 138, 139, 140, 141

Armco Steel Company: 149. Seea Z s o Piles, Armco.

Army, Eight h: 7, 10, 11, 12, 23, 32,33, 53, 71-79, 84, 92, 111, 146,150

Arnold, Lt . Col. Willar d D.: 126Asphalt : 46, 140Aspha lt bat h un its: 109, 150

* Roman page numbers refer to text;those in italics to photographs.

Assault boat s: 117

Badman , 1st Lt. Cur tis W.: 54, 68,130, 151

Baker , Col. William C., J r.: 77,146,147,148

Basalt : 51, 95, 96, 98, 132Bearing plates: 46, 132, 141Bedrock cha ra cterist ics: 49, 51, 52,

95,96 , 100,111, 126

Beggs, Col. Raymond W.: 103, 107,110, 111, 112, 113, 117, 119,123, 126, 139,148, 149, 150

Blackout shelters: 38, 46Block a nd ta ckle: 36Bowman, Br ig. Gen. Prank 0.: 113,

149, 150British Army

Independent Brigade, 28th: 4Bulldozers : 100, 104, 117

Bur leson, Lt . Col. C. W.: 79

Cables, anchor: 100, 130

Caissons. See Cofferdams.Cableways: 11

Carpenter shop: 54, 104, 107, 108,131, 138, 141

Car ter, Maj. William C.: 51, 52, 70,98, 99, 102, 103,106, 127, 146,147, 149

Catwalks: 138, 139, 140Causeways: 8, 10, 35, 42, 46, 50,

52, 55, 102, 104, 106; 107, 110,111, 114, 118, 120, 121, 122,123, 124, 125, 126, 127, 128,130,131, 134, 136, i37, 141

Cavalry Division, 1st : 4, 6, 7, 14

Chalmul: 7Chann el iron: 36, 102Civilian employees, Korean: 49, 54Clam buckets: 53, 103, 107, 109,

110, 112, 119, 122, 132, 133




Clar ke, Maj. Gen. Bruce C.: 151

Clay: 36, 125, 126

Clay spa des: 107, 114

Cofferdams : 34, 50-54, 55, 56, 57,

70, 83, 87, 98, 100, 101, 102,

103, 106, 107, 109, 110, 111,

112, 113, 115, 117, 118, 119,

129, 131, 132

Comm onwea lth Division, 1st : 7, 8,

47, 76, 147

Concrete. See ako Pours.cur ing: 69, 132

decking. See Decking, con-

crete.forms for: 117, 134, 136, 138

foun dat ions. See P iles, con-

cret e; Piers, r einforced

concrete.

mixture: 50, 103, 110, 112,

F--X_ 114,119,121,150

placement: 50, 51, 53, 54, 56,

59, 64, 69, 87, 103, 109,

110, 112-117, 119, 120,

121, 125-134, 136, 137,138, 140, 141

t est cores: 53, 114, 116, 117,

118

Concret e bat ch pla nt : 50, 55, 57,

58, 102-109, 123, 139, 149

Concret e cur ing cabins: 38, 46,

52-53, 55, 59, 103, 107, 113,

115, 117, 118, 119, 122, 123,

125, 149

Concrete mixers: 100, 102, 103,108, 148

Cons tr uction schedules (Teal

bridge): 86-90

Cooley, WO Harry: 54, 68, 106

Core dr ill rig: 114, 115, 116, 117,

118

Core dr illing t ests : 83, 85, 86

Corp oral Wr ight bridge: 4, 6, 13

Corps, I: 4, 6, 7, 8, 10, 11, 22, 23,

30, 31, 32, 33, 71-79, 146,151

Cost estimates: 76, 86-89

Cranes: 6, 10, 22, 32, 46, 53, 106,

108, 109, 110-117, 119, 123,

125, 127, 141

Crawler rigs: 10

Culverts: 107

Cur bs: 47, 65, 108, 136, 137, 141,

142

forms for: 54, 126, 132, 138,

1 4 1

Cut tin g torches: 108, 120, 121,

122,125, 139, 151

Daly, Col. Edwa rd : 8Dame r o n , 1st Lt. Melford , Jr.: 108,

115, 149Davis, Col. Hoy D., J r .: 139, 151

Debris, problems with: 30, 31-32,36,89

Decking: 41, 47, 54, 60, 61, 69, 86,

130, 133, 134, 139

concrete: 12, 64, 65, 68, 69,

86, 87, 88, 98, 100, 101,

134, 136; 140, 141

corr uga ted st eel: 68, 86, 88,

98, 101, 108, 114, 121,

126, 131, 13$, 136, 140,

1 4 1prefabrication ofi 131-132

tr eadwa y: 8, 10, 30wood: 47, 63, 86, 90

Demolition, p repa ra tion for (Libby

br idge): 69Demolition of pier s: 119, 120Dewatering: 51, .53, 107, 110, 111,

112, 113, 114, 126, 128, 129,

132

Diaphragming: 41, 54, 68, 119,120, 121, 125, 132, 133, 134,

139, 140, 141

Ditches: 123Divers: 10, 51, 110, 111, 112, 126,

127, 128, 129,132, 133

Dowel bar s: 115

Downing, Col. Ellswort h B.: 77,

126, 139, 148

Draglines: 126, 127-128

Drills: 104, 105, 112, 117. See ako

Core drill rig; Well drill rig.

DUKWs : 4,6

Dum p t ru cks: 6, 103, 105, 106

Dynamite: 36, 119



INDEX 16 3

Ea rt h-moving equipment : 107, 110

Eggleston, Lt. Col. Howard K., Jr*:

103, 104, 149

Eiler, Ma j. Keith E .: 129, 150

En emy fire: 4, 34, 69, 138, 139,

141, 151En gineer Aviat ion Br igade, 417th:

126

En gineer Combat Ba tt alions

8th : 6

14th : 4, 7, 11

74th: 130

1092d: 4, 7, 10

Engineer Combat Company, 72d :

10, 11En gineer Constr uction Batt alions

62d: 10, 12

76th: 149

84th : 7, 8, 11, 12, 23, 27, 35,

49, 98, 99, 108, 116, 146,

149,150, 151

En gineer Const ru ction Groups

2d: 27, 33, 35, 36, 49, 80-97,

99, 101, 102, 104, 105,

108, 116, 146, 148, 149, 150

32d: 117, 150

Engineer Dump Truck Compan y,

595th: 106

Engineer Field Maint enan ce Corn-

pa ny, 78th : 115, 118, 150

En gineer Group, 34th: 117, 150

Engineer Panel Bridge Company,

526th: 109Engineer Tr e a dway Bridge Corn-

pa ny, 58th : 4, 7, 11 ,

Engineers, Japanese: 83, 85, ‘l46

Engineers, Korean: 83, 85, 91, 146

Equipment. See also specifx equipment.

damage to and losses ofz 74,

106, 108

shortages: 105, 107, 108-111,

113, 114, 115, 116, 117,

119, 120, 121, 122, 128

Equ ipment shop: 104, 130

Excava tion: 107, 109, 110,

111-122, 126, 127, 128, 129,

131, 133

Fairchild, -Maj. Sam E.: 99

Farquhar, Maj. William R., Jr.: 27

Ferries: 49 6, 10, 32

Flat bed tr ailers: 114, 131, 149

Float ing br idges: 4, 6, 7, 30, 32,

77Floating M-2 t r e a dwa y bridges: 4,

6-7, 8, 10, 11, 15, 23, 74

Floods: 6-7, 10, 12, 22-23, 29-30,

31-32, 47, 52, 71, 73, 74, 77,

78, 82, 83, 84, 87, 89, 95-96,

123; 137

Footbridges: 4, 6, 8, 10, 125, 127,

128, 130, 131, 136Freedom Gat e br idge: 8, 10, 11, 12,

16, 18, 19, 22, 23, 30, 31~32 ,

33, 50, 76, 104. See aZso Mun -s ann i bridge.

I +ench dra ins: 35

Goldsmith, Capt . Edwar d H.: 35

Guardrails: 43, 45, 47, 54, 60

posts: 126, 128Gun emplacement s: 122-123, 151

H-beam s. See Whalers.Ha n River: 3, 96

Ha&an River: 3, 4, 7, 31, 32

Ha r d i n , Capt. A. W.: 35

Herm an Nelson equipment : 53,

100, 110, 148’

Him es, Lt. Col. William J .: 77, 92,

148,150

Hoists: 63, 6& 68-69, 141

Honker bridge: 4, 6-7, 8, 10, 13 ,

l& , 22, 85, 90

Hot-air blowers: 46, 53

I-beam s: 12, 22, 35, 39, 40, 46, 54,

68, 86, 87, 88

Ice floes: 10, 30, 74, 77

In ch’on: 103

Infantry Divisions

2d: 147

3d: 7625th: 139, 151

In ge, Lt. Col. Andrew: 10

It schner, Col. Emer son C.: 6, 7

.



164 0 BRIDGING THE IMJIN

Jackson, WO Peter: 151J apan , materials produced in: 50,

54,113,150

J effers , Maj. Henry A., Jr .: 27

Kaesong: 4, 6, 33, 77, 90Kangso-ri : 7Kelly, Cal. Hen ry J .: 111, 113, 118,

129,146, 148,150Kendall, Lt. Gen. P au l W.: 146

Kim Ho Duk, Cpl. (KATUSA): 70,150

Muckin g out: 51, 98, 111, 112, 114,125,126, 128,132,133,134

Mun sann i: 4, 33, 77, 78, 99, 106Mun s an n i br idge: 30, 31-32, 33,

76, 77, 78. See also FreedomGate bridge.

Klotch, Capt. Edward P .: 104 Nash, Maj. Leona rd C.: 105Korangpo-ri : 7, 8, 95 Navy, United Stat es: 10

Korea, Republic of, Army unit s Nishikimoto, 2d Lt. Ha rr y H.: 54Infantr y Division, 1st : 4, 8, Norris, Lt. Col. Willard: 1 02 , 1 04 ,14 1 105, 149

Light Ponton Company,9Olst : 8

Korea n Nat iona l Railway: 22, 114,115,116,117,118

Korean Augmentation to the U.S.Army (KATUSA) personnel:49,70 , 116

O’Grady, Pfc. James E.: 70, 130,151

Overbur den (in Imjin River): 29,

O’Grady, Lt . Cal. J am es R.: 35, 36,

49,51-52,82,85,88

118, 150

Lee, Lt.: 116Libby, Sgt. George D.: 67, 70Libby bridge: 3,21, 23, 27 33, 34,

48-70,98, 99-142, 149. Seealso X-Ray bridge.

Line Ja mestown: 8Line Wyoming: 7Long, Capt .: 102, 103, 105Low-level fixed bridges: 8, 10, 11.

See a Z s o Teal br idge.

Machine guns, mount ed: 122-123 ’McKenzie, 1st Lt. Dona ld W.: 52Maint enan ce building: 102Mallard bridge: 11, 22Manpower shorta ges: 107Mar ine br idge: 104, 105-106Mar ine Division, 1st : 76, 99, 100,

125,151Materials yar d: 104, 107Milburn , Maj. Gen. Prank W.: 4Min Byong Kwon, Br ig. Gen. (RQK

Army): 151

Mine clear ing: 99, 100Models: 54Motor park : 128, 130, 150Motors, problems wit h: 51, 52, 109,

110 -

Pa k, Lt.: 116Parker, Lt. Ca l . J ohn R.: 117, 150Parker Memorial bridge: 30, 31,

32 , 76. S ee ako P in ta i l bridge.Pa vers: 58, 59, 103, 105, 107, 108,

112, 113, 115, 122, 123, 125,126, 137, 148, 150 1

Pflueger, Capt . Willard T.: 106Piers. See a h o Piles.

diagona l bra cing for: 36, 38,12 0

reinforced concrete: 34, 86,87, 89, 98Pile br idges: 8, 11Pile dr ivers: 10, 104, 105, 106, 108,

109, 110, 111, 114, 123, 133,14 9

Pile dr iving: 35-36, 47, 50, 55, 56,102, 106, 107, 108-110, 111,117, 119, 120, 122, 126, 128,129,131,149

Piles

anchor: 100, 101



INDEX 165

Piles-Continued

Armco: 34, 35, 37, 39 , 53,

100; 101, 113

blowout s: 51, 53, 133

concret e: 22, 46, 78

misalignment of 36, 129, 132

penetration tests: 35, 46, 49, 89, 101

ra ilway ra ils used for: 23

split: 50, 51, 110, 111, 112,

117, 118, 119, 122, 129,

131, 132

Reinforced steel. See also Decking,corrugated steel.

girders: 46, 54, 63, 64, 68-69,

119, 128, 130, 131, 132,

133, 137, 139, 140, 141,

150

steel: 12, 34, 50-51, 87, 88;.

98, 99, 102, 104, 106,

107,114, 129,131, 149

timber : 12, 22, 32P i n t a i l bridge: 7, 11, 12, 17, 22,

23, 30, 31, 32, 76

Pn eum at ic tools: 107, 112Ponton ra fts: 4

Pontoon bridges: 104, 134, 137

Pours. See aho Concrete.

A: 51, 53-54,56, 107, 111,

. 112, 113, 114, 116, 128,

133, 134

launching of 125, 127, 128,

130, 131, 133, 134, 137,

138, 139, 140, 141lau nching noses: 62, 63, 68, 128

prefabricat ed ma ts: 54, 60,

69, 138

prefabrication of 113, 115,

118, 119, 122, 130, 131,

132, 134, 137, 138, 139Reinforcing rods: 12, 100, 101, 102,

108,115, 116

Ribbs, Col. Edwar d J .:‘lll, 117,

139, 150

Rip ra p: 125, 137, 138

Riverbed featu res : 12, 36, 49, 83,

85, 88, 92, 93, 94-97, 111, 112,

114, 122

B: 53-54, 115, 116, 117, 127,

130, 134

bear ing capa city: 83, 92

boulders: 36, 51, 112, 114,

121, 122, 126C: 53-54,59, 118, 119, 127,

128,; 130, 134, 150

D: 53-54,59, 119, 120, 130,

131, 134,136, 137-138

E: 53-54,59, 120, 121, 130,

131, 136, 137-138

Power gener at ors: 102, 103, 105,106, 113, 114, 116, 118

Power s hovels: 104Pumpcrete plant: 53-54, 58, 59,

M, 69, 112, 113, 115, 116, 117,119, 122, 123, 126, 127, 128,

131, 132, 138, 150Pu mps : 51, 107, 109, 110, 112, 115,

117, 120, 121, 122, 126, 128,

131, 132, 133, 141

Pu sa n: 100, 102, 104, 105

Pu sey, Maj. J ohn D.: 93, 148

Riveters: 61, 62, 117, 118school for : 116

Rivetin g: 54, 116, 117, 120, 125,

132, 133, 134, 138, 139, 150

Riveting equipm ent : 54, 113, 115,

116, 139

Rock crush ers: 100, 106, 134Rock-filled crib-pier br idges: 8, 10,

. 11, 15, 22, 23, 30

Rum aggi, Col. Louis J .: 111, 118,

126, 147

SFnd : 106, 107, 121, 122, 125, 126,

127, 128, 130, 133

Scaffolding: 113, 127, 130, 136,

138, 151

Scott , 1st Lt. Ja mes J ., J r.: 123,

15 0

Railroad bridges: 6, 8, 10, 11, 12,

16, 18, 33, 76, 77, 78

Rapids: 96

Scouring: 52, 82, 126

Sorley, Col. Mer row E .: 22, 146

Spoonbill bridge: 21 , 23, 106, 137,

14 8



166

St iffeners: 54, 98, 108, 119, 125,132, 150

Stoudem ire, Maj. Daniel 0.: 149Suspension bridges: 10, 11

Tansey, Maj. Gen. Pat rick Henry:130, 151Taylor, General Maxwell D.: 70,

142Teal bridge

high br idge: 7, 12, 16, 18, 19,

20, 22, 23, 30, 31, 32, 71,74, 76, 77, 84

submers ible bridge: 3, 23, 27,33, 34, 35-47, 50,71-79,

80-97, 99, 104, 105, 106,107,108-109,118, 138,150

Tides, dam age from: 8, 10, 30, 52,121,122, 130, 137

Timber-bent bridges: 11Timber-trestle br idges: 12, 22Tongduchonni : 115, 150nac to r s : 36, 149, 150Training: 116

Tremies: 53, 111, 112

Urn Hong Sub, Brig. Gen. (RQKArmy): 141, 151

United Nat ions delegates: 6, 13

United Nations forces: 3, 4, 6, 23Ut ility boat s: 4, 131

Van Fleet, Genera l J ames A.: 73,79,146

Vibra tors: 112, 113, 116, 117, 119,131

BRIDGING THE IIMJIN

Water heaters: 107

Wat ers, Brig. Gen. J ohn K.: 72, 75

Welders: 36, 49, 110, 119, 121, 125,

138Welding: 36, 38, 46, 52, 68, 110,

137, 139, 140, 141Welding equipment: 108, 109, 113,

114, li8, 120, 122, 125Well drill r ig: 107, 110, 117, 118West, Maj. Gen. M. M. A-R-: 47Whalers: 36, 47, 57, 84, 89, 102,

110, 111, 112, 121, 122, 125,127,129, 131, 132,133, 150

Whist ler br idge: 4, 6, 10 ; l#, 15, 22Whitefront br idge: 7, 10, 12, 15 ,

17,20 , 23, 30, 31, 76, 138Widgeon br idge: 7, 10, 22-23, 30,

31-32Winches: 35Wing walls: 107-108, 110, 112,

122,123,125

Wire: 123Wright, Corporal, br idge. see C a r -

poral Wright bridge.Wright, Cpl. Theodore: 4

X-Ray bridge: 8, 10, 12, 22, 23, 30,31, 32, 71, 74, 75, 76, 77, 78,90. see ako Libby br idge.

Yawata St eel Compa ny: 119, 150Yokkok River: 3

*Yokohama Equipment Depot(Ja pan): 103, 104, 105

Yongsan-ni: 95-96Yongsann i ferr y: 94, 95-97, 148

Zwick, Maj.: 126

*us. Go- PRINTING OFFICE : 1992 0 - 325781



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