GeohazardsGeohazards in Transportationin TransportationAppalachian Region Technical ForumAppalachian Region Technical Forum

August 1August 1--2, 20072, 2007

““Drilled Shafts for Bridge Foundation Drilled Shafts for Bridge Foundation Stability ImprovementStability Improvement

Ohio 833 Bridge over the Ohio RiverOhio 833 Bridge over the Ohio River””An UpdateAn Update

Meigs County, OhioMeigs County, OhioMason County, West VirginiaMason County, West Virginia

ByByStan Harris, P.E. and Eric Kistner, P.E.Stan Harris, P.E. and Eric Kistner, P.E.

FMSM EngineersFMSM Engineers

AgendaAgendaI.I. Introduction/BackgroundIntroduction/Background

A.A. GeneralGeneralB.B. Initial Slope MovementInitial Slope MovementC.C. Remediation SchemeRemediation SchemeD.D. Instrumentation PlanInstrumentation Plan

II.II. Instrumentation Results/Recent Slope Instrumentation Results/Recent Slope MovementMovement

III.III. New Instrumentation on Existing BridgeNew Instrumentation on Existing BridgeIV.IV. Lessons LearnedLessons LearnedV.V. Question/AnswerQuestion/Answer

I. Introduction/BackgroundI. Introduction/Background

Project LocationProject Location

Pomeroy, Ohio

Project TeamProject Team

Owner: ODOT/WVDOHOwner: ODOT/WVDOHDesigner: URS CorporationDesigner: URS CorporationContractor: Mahan/National Joint Contractor: Mahan/National Joint

VentureVentureGeotechnical Consultant Geotechnical Consultant –– FMSM FMSM

Existing StructureExisting StructureOHIO

WEST VIRGINIA

Proposed StructureProposed Structure

WEST VIRGINIA

OHIO

Project TimelineProject Timeline2000 2001 2002 2003 2004 2005

FMSM Geotechnical Exploration

Bridge DesignBridge Construction

Slope MonitoringSlope Movement Detected

Construction of Protective Measures

Monitoring of Protective Measures

20072006

Monitoring of Existing Bridge

Current State of ConstructionCurrent State of Construction

Stability Issues/Slope Movement/ReactionStability Issues/Slope Movement/Reaction

New Main Street EmbankmentNew Main Street EmbankmentShortShort--Term Stability ConcernsTerm Stability ConcernsControlled RateControlled Rate--ofof--FillFill–– Slope InclinometersSlope Inclinometers–– PiezometersPiezometers

Initial Detection of MovementInitial Detection of MovementAdditional InstrumentationAdditional Instrumentation

Original Extents of Slope MovementOriginal Extents of Slope Movement

Approximate Limits of Slope

Movement

Probable Causes of Slope Probable Causes of Slope MovementMovement

Weak slickensided clay shale Weak slickensided clay shale (mudstone)(mudstone)Possible ancient movementPossible ancient movementConstruction activity/embankmentConstruction activity/embankmentRapid drawdown cycles of Ohio RiverRapid drawdown cycles of Ohio River

Slope Geology/GeometrySlope Geology/Geometry

Shale/Clay Shale/Mudstone Bedrock

Alluvial Silt and ClayExisting Fill

New Fill

Ohio River

Apparent Failure Surface

Residual Clay

Siltstone

Ohio River

Potential Failure Surface

Siltstone

ODOTODOT’’s Preferred Option s Preferred Option and Related Decisionsand Related Decisions

One Row of Nine Drilled Shafts Between the Land Pier and the Water Pier

Realign Main Street to Reduce Fill Height

Touch Down PierAbutment

Ohio Tower

NEW BRIDGE

Change Abutment and Land Pier Foundations to Drilled Shafts

Plan View of Stabilization ShaftsPlan View of Stabilization Shafts

8’ Diameter Drilled Shafts on 12’ c/c

Spacing

Revised Roadway PlanRevised Roadway Plan

Instrumentation PlanInstrumentation Plan

Site Site –– Slope Inclinometers, PiezometersSlope Inclinometers, PiezometersExisting Bridge Existing Bridge –– Tiltmeters, Survey Tiltmeters, Survey TargetsTargetsTouch Down Pier Touch Down Pier –– Strain Gauges, InStrain Gauges, In--Place and Manually Read InclinometerPlace and Manually Read InclinometerStabilization Shafts Stabilization Shafts –– Tiltmeters, Strain Tiltmeters, Strain Gauges, InGauges, In--Place and Manually Read Place and Manually Read InclinometersInclinometers

Stabilization Shaft Instrumentation PlanStabilization Shaft Instrumentation Plan

II.II. Recent Slope Movement/ Recent Slope Movement/ Instrumentation ResultsInstrumentation Results

Recent Movement (Oct Recent Movement (Oct ’’06 06 -- Feb Feb ’’07)07)

DetectionDetection–– Instrumentation Activity (late October)Instrumentation Activity (late October)–– Tension Cracks (early December)Tension Cracks (early December)–– Water Main Break (early December)Water Main Break (early December)

CausesCauses–– Construction ActivityConstruction Activity–– River FluctuationRiver Fluctuation

Tension Cracks Tension Cracks –– 12/11/0612/11/06

Construction Activity Construction Activity –– 11/30/0611/30/06

Ohio River FluctuationsOhio River FluctuationsRiver Elevation (feet)

520.0

530.0

540.0

550.0

560.0

570.0

580.0

10/1

/04

12/1

/04

2/1/

05

4/1/

05

6/1/

05

8/1/

05

10/1

/05

12/1

/05

2/1/

06

4/1/

06

6/1/

06

8/1/

06

10/1

/06

12/1

/06

2/1/

07

Slope Movement

Tied Back Retaining WallTied Back Retaining Wall

Results of InstrumentationResults of InstrumentationSiteSite–– 4 Years of Data4 Years of Data–– Numerous Inclinometers Sheared Due to Slope Numerous Inclinometers Sheared Due to Slope

MovementMovementExisting BridgeExisting Bridge–– 3 Years of Data3 Years of Data–– Abutment Tilt Due to Recent MovementAbutment Tilt Due to Recent MovementNew Bridge Touch Down PierNew Bridge Touch Down Pier–– 3 Years of Data3 Years of Data–– Top Deflection Due to Lateral LoadingTop Deflection Due to Lateral LoadingStabilization Shafts Stabilization Shafts –– 2 Years of Data2 Years of Data–– Northernmost Shaft Being LoadedNorthernmost Shaft Being Loaded

Current Extents of Slope MovementCurrent Extents of Slope Movement

Limits of Movement

Existing Bridge Tiltmeter ResultsExisting Bridge Tiltmeter Results

11/01/2004

12/01/2004

01/01/2005

02/01/2005

03/01/2005

04/01/2005

05/01/2005

06/01/2005

07/01/2005

08/01/2005

09/01/2005

10/01/2005

11/01/2005

12/01/2005

01/01/2006

02/01/2006

03/01/2006

04/01/2006

05/01/2006

06/01/2006

07/01/2006

08/01/2006

09/01/2006

10/01/2006

11/01/2006

12/01/2006

01/01/2007

02/01/2007

03/01/2007

04/01/2007

05/01/2007

06/01/2007

07/01/2007

08/01/2007

09/01/2007

Time

-0.15

-0.10

-0.05

0.00

0.05

0.10

0.15

Tilt

(deg

)AbutmentLand Pier TopLand Pier BottomWater Pier Top

Zeroed Y-Tilt ReadingsPositive → Top Moving Downslope

Abutment

Land Pier Top

Land Pier Bottom

Water Pier Top

Instrument Malfunction Instrument Malfunction

Existing Bridge Tiltmeter ResultsExisting Bridge Tiltmeter Results

-30 -20 -10 0 10 20 30 40 50 60Temperature (C)

-0.15

-0.10

-0.05

0.00

0.05

0.10

0.15

-20

-10 0 10 20 30 40 50 60 70 80 90

100

110

120

130

140

Temperature (F)Temperature Influence on Y-Tilt Readings

-30 -20 -10 0 10 20 30 40 50 60Temperature (C)

-0.15

-0.10

-0.05

0.00

0.05

0.10

0.15

Tilt

(deg

)

-20

-10 0 10 20 30 40 50 60 70 80 90

100

110

120

130

140

Temperature (F)Temperature Influence on X-Tilt Readings

Land Pier Top Tiltmeters

Looking Upslope, P

ositive → C

lockwise Tilt

Positive → Top M

oving Dow

nslope

First Track:Oct-2004 – Mar-2005

Second Track:Aug-2005 – Oct-2006

Third Track:Oct-2006 – Dec-2006 Fourth Track:

Dec-2006 – Feb-2007

Fifth Track:Feb-2007 – July-2007

Stabilization Shaft Strain Gage ResultsStabilization Shaft Strain Gage Results

-6000 -5000 -4000 -3000 -2000 -1000 0 1000 2000 3000 4000 5000 6000Moment (kip-ft)

460

470

480

490

500

510

520

530

540

550

Ele

vatio

n (ft

)

LPILE 0.2"21-Oct-200604-Nov-200618-Nov-200602-Dec-200616-Dec-200630-Dec-200614-Jan-200728-Jan-200711-Feb-200725-Feb-200711-Mar-200725-Mar-200708-Apr-200722-Apr-200706-May-200720-May-200703-Jun-200717-Jun-200701-Jul-200715-Jul-2007

SS9: Moment Diagram

Cra

ckin

g M

omen

t

Cra

ckin

g M

omen

t

Bottom of Shaft

Top of Rock

Top of Shaft

With Linear RegressionDarker =

More Recent

Positive Moment ⇒ Tension on Upslope Face

Stabilization Shaft 9 Stabilization Shaft 9 –– IPI PlotIPI Plot

Touch Down Pier Strain Gage ResultsTouch Down Pier Strain Gage Results

09/01/0410/01/0411/01/0412/01/0401/01/0502/01/0503/01/0504/01/0505/01/0506/01/0507/01/0508/01/0509/01/0510/01/0511/01/0512/01/0501/01/0602/01/0603/01/0604/01/0605/01/0606/01/0607/01/0608/01/0609/01/0610/01/0611/01/0612/01/0601/01/0702/01/0703/01/0704/01/0705/01/0706/01/0707/01/0708/01/0709/01/07

Time

-6000

-5000

-4000

-3000

-2000

-1000

0

1000

2000

3000

4000

5000

6000

Ben

ding

Mom

ent (

kip-

ft)

El. 530 ftEl. 534 ftEl. 542 ftEl. 566 ftEl. 576 ft

DS-54: Bending Moment History

Cracking Moment (approx. 30% of Moment Capacity)

Cracking Moment (approx. 30% of Moment Capacity)

III. New Instrumentation on III. New Instrumentation on Existing BridgeExisting Bridge

–– Jointmeters Jointmeters (3 Joints on (3 Joints on Ohio Side)Ohio Side)

–– Tiltmeters on Tiltmeters on Linkage Linkage AssembliesAssemblies

–– Strain Gages Strain Gages on Truss on Truss MembersMembers

IV. Lessons LearnedIV. Lessons LearnedDifficulty with Instrumentation Durability in Difficulty with Instrumentation Durability in Construction/River EnvironmentConstruction/River EnvironmentSoleSole--Source Instrumentation ConsultantsSource Instrumentation ConsultantsCommunication Between Contractor and Communication Between Contractor and Engineer KeyEngineer KeyBetter Results from Tiltmeters/Strain Gages Better Results from Tiltmeters/Strain Gages than than IPIIPI’’ssLook for Agreement Between InstrumentsLook for Agreement Between InstrumentsHuman Intervention with Instruments Human Intervention with Instruments Necessary At TimesNecessary At TimesInstallation and Access Can Be DifficultInstallation and Access Can Be Difficult

V. Questions/AnswersV. Questions/Answers

“Drilled Shafts for Bridge Foundation Stability Improvement�Ohio 833 Bridge over the Ohio River”�An Update��Meigs County, OhAgendaI. Introduction/BackgroundProject LocationProject TeamExisting StructureProposed StructureProject TimelineCurrent State of ConstructionStability Issues/Slope Movement/ReactionOriginal Extents of Slope MovementProbable Causes of Slope MovementSlope Geology/GeometryPlan View of Stabilization ShaftsRevised Roadway PlanInstrumentation PlanStabilization Shaft Instrumentation PlanRecent Slope Movement/ Instrumentation ResultsRecent Movement (Oct ’06 - Feb ’07)Tension Cracks – 12/11/06Construction Activity – 11/30/06Ohio River FluctuationsTied Back Retaining WallResults of InstrumentationCurrent Extents of Slope MovementExisting Bridge Tiltmeter ResultsExisting Bridge Tiltmeter ResultsStabilization Shaft Strain Gage ResultsStabilization Shaft 9 – IPI PlotTouch Down Pier Strain Gage ResultsIII. New Instrumentation on Existing BridgeIV. Lessons LearnedV. Questions/Answers