T[(HNl(AL REPORT 5-TANrA~D 11Tlf PAGf
TX-84/105-lF
~~RGENCYOPENING SYSTEM FOR AN AUTHORIZED VEHICLE
Ne,
R. Morgan, and Research Report 105-lF
John W. Strybos, James Hayes E. Ross, Jr.
----····-----Y_ P~rl!'\rm1n9 O,q-,n,1.;:it,on N::nne o<>d Add,e~s
--------------- ---~----:,:--,--,-,----,------------------i Work Un,1 No
exas Transportation Institute e Texas A&M University System
College Station, Texas 77843
l 2 Sp011ior,n9 A9en,;:y Nome ond Ad<i'e,,;
Houston Urban Project State Department of Highways and
Public Transportation P.O. Box 187; Houston, Texas 77001
~n emergency opening system {EOS) for an authorized vehicle lane was developed and crash tested. The design consisted of two steel box tubes mounted on top of each other. The beams were supported by pins at the ends that were connected to modified concrete median barrier sections. Factors considered in the development of the system were ease of operation and ability to redirect errant vehicles.
Three full-scale crash tests were conducted to evaluate the impact behavior of the design""."l All of the occupant risk values as well as the vehicle trajectory hazard were below recommended va1ues for all of the crash tests. ln addition, the EOS was still operational after the first two tests. The system was not operational after the third test because the anchorage system for the downstream concrete median barrier failed. Several modifications in the design of the EOS were recommended to improve the operation of the system. These changes were a
I result of observations of the construction and crash testing of the system.
I
117. Koy Wo,d, 18. o,,,,,buhon S••••m .. t ····-----1 \ Median Barriers, Authorized Vehicle Lane , No restrictions. This document is I , Emergency Opening System, Traffic Bar- , available to the public through the
22 p,,c. J l_~~c~~-sified _________ ~~~~ass~f-ied_~. ___ 61 ----'------· ____ -·- _
Fo•m DOT F 1700.7 1•·•••
EMERGENCY OPENING SYSTEM FOR AN
AUTHORIZED VEHICLE LANE
by
John W. Strybos James R. Morgan
and Hayes E. Ross, Jr.
Research Report 105-lF on
IAC(84-85)-0664 Emergency Opening System for Authorized Vehicle Lanes
Sponsored by Houston Urban Project of the
Texas State Department of Highways and Public Transportation
Texas Transportation Institute The Texas A&M University System College Station, Texas 77843
March 1984
DISCLAIMER
The contents of this report reflect the views of the authors
who are responsible for the opinions, findings, and conclusions
presented herein. The contents do not necessarily reflect the
official views or policies of the Texas State Department of
Highways and Public Transportation or the Houston Urban
Expressway Office. This report does not constitute a standard,
specification, or regulation.
KEY WORDS
Median Barriers, Authorized Vehicle Lanes, Emergency Opening
System, Traffic Barriers, Crash Tests, Highway Safety
ACKNOWLEDGMENTS
This research study was conducted by the Texas
Transportation Institute (TTI) for the Texas State Department of
Highways and Public Transportation (SDHPT). Technical liaison
and guidance was provided by William v. ward, Engineer-Manager
and James G. Darden,III, Associate Designing Engineer of the
Houston Urban Project of SDHPT. The crash tests were carried out
by personnel of the Highway Safety Research Center of TTI. This
report is based on a Master of Engineering report by John w.
Strybos.
IMPLEMENTATION STATEMENT
At the writing of this report the concepts and designs
presented herein are being implemented on the I-45 Authorized
Vehicle Lane project in Houston, Texas.
ii
ABSTRACT
An emergency opening system (EOS) for an authorized vehicle
lane was developed and crash tested. The design consisted of two
steel box tubes mounted on top of each other. The beams were
supported by pins at the ends that were connected to modified
concrete median barrier sections. Factors considered in the
development of the system were ease of operation and ability to
redirect errant vehicles.
Three full-scale crash tests were conducted to evaluate the
impact behavior of the design. All of the occupant risk values
as well as the vehicle trajectory hazard were below recommended
values for all of the crash tests. In addition, the EOS was
still operational after the first two tests. The system was not
operational after the third test because the anchorage system for
the downstream concrete median barrier failed. Several
modifications in the design of the EOS were recommended to
improve the operation of the system. These changes were a result
of observations of the construction and crash testing of the
system.
i i i
TABLE OF CONTENTS
INTRODUCTION
ANALYSIS
EMERGENCY OPENING SYSTEM
CRASH TEST RESULTS
SUMMARY AND CONCLUSIONS
APPENDIX A - DATA ACQUISITION SYSTEMS
APPENDIX B - SEQUENTIAL PHOTOGRAPHS
APPENDIX C - ACCELEROMETER TRACES AND PLOTS OF ROLL, PITCH, AND YAW RATES
REFERENCES
iv
~
1
2
4
14
34
42
44
51
61
LIST OF FIGURES
Figure~
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Emergency Opening System for Authorized Vehicle Lane
Emergency Opening System
Emergency Opening System in Operation
Summary of Test 1
Test Vehicle Before and After Test 1
Test Installation Before and After Test 1
Summary of Test 2
Test Vehicle Before and After Test 2
Test Installation Before and After Test 2
Summary of Test 3
Test Vehicle Before and After Test 3
Test Installation Before and After Test 3
Design Modifications for Emergency Opening System
Sequential Photographs for Test 1
Sequential Photographs for Test 2
Sequential Photographs for Test 3
Vehicle Longitudinal Acceleration Trace for Test 1
Vehicle Lateral Acceleration Trace for Test 1
Vehicle Angular Displacement for Test 1
Vehicle Longitudinal Acceleration Trace for Test 2
v
5
9
10
16
19
20
22
24
25
28
29
30
36
45
47
49
52
53
54
55
LIST OF FIGURES (continued)
Figure liQ...
21
22
23
24
25
Vehicle Lateral Acceleration Trace for Test 2
Vehicle Angular Displacement for Test 2
Vehicle Longitudinal Acceleration Trace for Test 3
Vehicle Lateral Acceleration Trace for Test 3
Vehicle Angular Displacement for Test 3
vi
56
57
58
59
60
Table .HQ...
1
LIST OF TABLES
Summary of Crash Tests
vii
~
15
INTRODUCTION
A $52 million project is underway in Houston to install
an authorized vehicle lane (AVL) down the center of Interstate
45. This AVL will provide buses, van pools, and other authorized
traffic with an expressway free from normal traffic congestion
over a distance of 13.l miles (21.l km). Concrete median barriers
(CMBs) will be used to separate traffic within the AVL from the
normal I-45 traffic. Limited access to the AVL will insure
smooth flow uninterrupted by unauthorized vehicles. However, in
the event of a mechanical problem, minor breakdown (e.g., flat
tire, etc.), accident or other emergency, this limited access
also will impede the wrecker or other emergency equipment,
causing major traffic congestion. Such eventualities make the
implementation of a gate or emergency opening system (EOS) for
the AVL essential.
The design of an EOS for a CMB involves several key
parameters. The EOS must function as a median barrier in its
ability to safely redirect errant vehicles and stop them from
entering adjacent traffic lanes. This should be achieved without
endangering the driver during vehicle redirection. At the same
time, the EOS must be opened and closed by the operator of the
emergency vehicle. This requires that the EOS either be
lightweight or include provision for mechanical or electrical
devices to aid in its operation. Futhermore, it would be
desirable to have an EOS that would remain operational following
moderate impacts with little or no maintenance. Guidelines and
designs also are needed to properly transition the CMB both on
the upstream and downstream ends of the EOS.
l
ANALYSIS
The EOS is designed to safely redirect errant vehicles and
stop them from entering adjacent traffic lanes. The general
configuration of the gate system is a steel beam 30 ft. (8.9 m)
long that is connected to modified CMB sections at each end. A
square tube was selected for the beam section based on a
preliminary analysis of the system. The beam was pinned at the
ends so that the gate could be opened and closed by an emergency
vehicle operator.
When impacted by an errant vehicle, the EOS should behave
similarly to a guardrail system. Both barriers can be modelled
as a series of rigid beams connected together at joints. The EOS
was therefore analyzed with a computer program developed to
analyze the behavior of an automobile
barrier of general configuration (il.
striking a deformable
For a description of the
computer model the reader should refer to the referenced report.
In the computer program, a dynamic, inelastic large
displacement structural analysis problem in two dimensions is
solved using a step-by-step method. The automobile is modelled
as a plane body of arbitrary shape surrounded by inelastic
springs. During impact, the automobile slides along the barrier.
Forces between the automobile tires and the pavement are taken
into account,
automobile and
as
the
well as the interaction forces between the
barrier. The barrier is an arbitrary
assemblage of beams, posts, springs, and damping devices. Loads
2
are applied to the barrier only at the nodes.
Impact with a large, 4500 lb (2040 kg) vehicle travelling at
60 mph (96.6 km/h) and 25 degrees was investigated. The joint
loads and deflections from this simulation were used to design
all of the appurtenances of the EOS. Impact with an 1800 lb (815
kg) vehicle travelling at 60 mph (96.6 km/h) and 15 degrees was
also investigated. This simulation gave smaller loads and
deflections than the impact with the large vehicle.
The EOS was modelled as a system of 20 beams. Each beam was
16.7 in. (42.4 cm) long with a centerline height of 19 in. (48.3
cm) above the pavement surface. In addition, there were two
support posts in the model. The posts were placed at the initial
node and at the terminal node of the model. The posts were given
arbitrarily high values for the stiffness, base moment at
failure, shear force at failure and deflection at failure because
the computer simulation was performed to test the strength of the
barrier itself, not the strength of the support posts. This
accurately models the situation of a rigid CMB support.
3
EMERGENCY OPENING SYSTEM
The EOS must perform as a median barrier in its ability to
safely redirect errant vehicles and stop them from entering
adjacent traffic lanes. Futhermore, the EOS must be opened and
closed by the operator of the emergency vehicle. Finally, the
barrier should be relatively inexpensive to build and maintain,
and it should not be too difficult to install in place.
Design of a system to satisfy these requirements presents
special problems. Consultation with several state highway
departments found that there was not a system presently in
operation that would satisfy all of these requirements. The
first function of the EOS was achieved by using two square
steel tubes mounted on top of each other, but separated by 1.38
in. (3.5 cm) vertically. The size and orientation of the steel
members was selected based on information from the computer
analysis. The tubes were mounted between two 30 ft (8.9 m)
long modified concrete median barrier sections that were
separated by 30 ft (8.9 m). The emergency opening system is
described in detail by Figures land 2. Figure 3 shows the
system in operation.
The other parts of the EOS were designed, using the
applicable standards (~), from peak loads taken from the
computer simulation. These loads were 250 kips (34.6 kN) axial
and 50 kips (6.9 kN) lateral shear. The steel members
transferred these forces to one 3.25 in. (8.3 cm) diameter pin at
each end of the tubes. The pins were sized to carry the loads in
4
L)l
PLAN i:':'-0
,, "'""
ELEVATION .::.. ..
LONGITUDINAL SECTION .. C:::S ,·
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Tl!XAI TRANSPORTATION INSTITUTE THE TEXAS AIM UHIYERSITY SV$T.:JII
AUTHORIZED VEHICLE LAN£. EMERGENCY OPENING SYSTEM
AS eUILT-STEEL GATE
i=--·-'-'c'-"c"-'--i-c~-'c'-'c~c'c·_'_"_' ____ -1•"'''"''"...,~ 1 or 4
E1c1ergenC)' Ooenin:i S;•ster,1 for l\utl1orized Vehicle Lane,
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CRA~ MA" 6F TQP MOUNTED · I REOU\JnNG ACCESS TO JACK w THAQl)(JH HAM. JA.CK HAt«.>LE NOT TO PROTRIJOE. INTO TRA.FflC O LANE WHILE NOT IN use \"· g
SECTION A-A
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HANO CRANKED JACK W{CA.STER A$$£1.eL Y ,\$ MANI..JFACTl..fEI BY HOlLANO Hn'(;tt CO. PO aox 30)$, '430 W 18TH ST, HOU.AHO, Ml. "49423 JACK TO BE ABlE TOLlfT VERTICAL .!-3 l~S HOU.A.NO HITCH OR APF41:0V§P EOUA\~ JS-300-J a
END ELEV A TION ···---
GENERAL NOTES
ALL S1EEL TO BE ASTM A512 GRADE 50 UNLESS OTHERWISE $PEClfi£0 ?f<OVIOE SQTH PINS !J 114• DIA.!, 314" DIA l AT BOTH ENDS
ALL WELDS E10X)( ELECTRODES
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NOTE GATE SHOWN IN ()PEN POSITION
SECTION 8----8 . -·-TEXAS TRANSPORTATION INSTITUTE THI TEXAS AAM UNIVERS~TY SYSTl!M
AUTHORIZED VEHICL[ LANE EMERGENCY OPENING SYSTEM
AS SU!LT-STEEL GATE DETAILS
2 ot 4
Figure l. Emergency Opening Systen for Authorized Vehicle Lane. (continued)
30 D --····- - ---··· -- ··------ ·····-
2:, n v2 ---- -----
O CO" '.'.HAMf(P Al I. COA~j! RS
UPSTREAM TRANSITION SECTION
,· o:..___ f'+ ,,· 4---
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ELEVATION •
DOWNSTREAM TRANSITION SECTION
L-.AST SPACE W\!.l.. S.E 7''
SECTION (TYPICAL)
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lll.\> WITh ';'1'?\CAL # S SARS i.lS'E 24" LAP SPUCE St:.1'0#5 BARS IN TO MATCH #14 8AIIS
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Figure 1. Er,1ergency Ooening S:•sten for Authorized Vehicle Lane.
FLEVATION
FLfVATION
Tix.-• T11&11s..0RTATl0N IHs,,,u,a: TH• TRXAI AIM UNIYERltTY SYSTEM
AUTHORIZED \IEHCLE lAtE Er.ERGENCY OPENNG SYSTEM
AS 0\Jtl l CONCRETE BAfffflER DETAILS
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(continued) ·
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UPSTREAM END SECTION C-C ~------
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STIRRUP DETAIL FOR SECTION C-C
DOWNSTREAM END SECTION D-0
NOTE: $HADED ... 1 .. BARS iSEE sect.c-c 6 0-0) TEAMINA.TEO SY RES,.A FLA.NOE CotP!..ER, W!Lt.u.MS FOAM ENGIIEERING CORP •• QRANl AAPOS, Mi!CtOOAN. OR
&!MIL.AR "P1,10DUCT. AESAA IS THREADED INTO 3• Cf' COUPLER f'!,,ANQE COUPLER IS lot TEO OR NAIL[O TO FORM FOR
FA.SfflCATION. ENO Of REB,t,R 18 THREADED TO -FIT FLAMGE COOPI-Eft LAST 3' Of J;lt:81,R IS nR:Al')Ep 1 112' DIA 1( 6,C::._
'
STIRRUP DETAIL FOR SECTION D-0
FL.ANGE COUPLER '-1!_5.iidiia._ 0 ,.
MQTI., ALL COffCRETE SHALL BE CLASS "C' IN THE LATEST EOtTION_Of SbHPT SPECIFICATIONS Ai.L REIHfOAC£.MENT IS GRADE 80
NOTI.: ST!fU\UP $PACING FOR HINGED 'ENO AND LATCHED "'NO SECTIONS ARE TYPICAi..
N()TI: REGAROl.ESS OF' ME:THOO OF HAt«>i.lNG. 61\RRIER
ffli!CtlON LlfTHl POINTS $HAll,. BE 6_2S FT fllOt,I Tt-E
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TaxAa TRANIPORTATION INSTITUTE THa TaXA• A.All UNIV.R$fTY SYSTE ..
AUTHORIZED VEHICLE LANE EMERGENCY OPENING SYSTEM
AS BUIL 1 CONCRETE BARRIER OETA.1\.$
Ehl.)$ Of' TIE 8ARRl£R LIFTING DEVICES AN'.} ATTACHMENTS .----•-'·-=-•-· -;._;,u_,~·~M~•~· '-'-"----lSH•tr -TO BARRIER SECTION SHALL BE APPl'IOVCO SY THE ENGINEER ""'°""'P•Y--it.t-" llf~lllO#Ollll' ocroeu,, lHl 4 Of 4
Figure l. Emergency Opening System for Authorized Vehicle Lane. (continued)
Figure 2. Emergency Opening System.
9
0
90'--{)"
30'-<l"
lFSTREAM TRANSITION SECTION DOUBLE 8" SQUARE TUBE GATE -O' 4'-o"
PLAN WITH GATE CLOSED
--. . ;,
SECTION AT UPSTREAM TRANSITION MEMBER (SHOWINO #1A'• on! #A AEINFOFICING BARS)
O' 1'-(1" 2'-o'
GATE BEING OPENED BY EIERGENCY ----VEHICLE PUSHWG WITH 81..M'ER
PLAN WITH GA TE BEING OPBED
PLAN WITH GATE BEING CLOSED
\ \ I I
3Q·--o---
DOWNSTREAM TRANSITION SECTION
a• x8" x3/8" STEEL TUBE
INSERT C3x6 STEEL CHANN'.L ASTM A36
-------- HAJII) CRANKED JACI< ASSEt.el. Y ,
:1.-...l~--Wl-TH FIXED CASTER
SECTK>N AT JACK/CASTER ASSEMBLY
o• 1'-o" 2·-0·
EMERGENCY GATE BEING CLOSED wmt
WENCH ON EMERGENCY YEl9CL.E
(CABLE AROlN> REMOVABLE PIN)
Tl!!:XAS TRANSPORTATION INSTITUT• THE TEXAS A&II UNIVIRSITY SYSTI!!: ..
AUTHORIZED VEHCLE l..AfE EMERGENCY OPENNG SYSTEM
SCHEMATIC
ORAWNn,G.R.S DATE: JIA.Y, 19U SHEET-Ell:
-OVEII BY, H.E.R. REV/$,0,. IJATE, OCTOIIER. 19'3 1 o, 1
Figure 3. Er.1ergenc;' Opening Syste"1 in Coeration.
quadruple shear. The pins transferred the load to three tongue
plates. The tongue plates were welded to a base plate that was
attached to the concrete median barrier section by eight 1.5 in.
(3.8 cm) diameter anchor bolts. The anchor bolts were screwed
into rebar flange couplers manufactured by Williams Form
Engineering Corporation of Grand Rapids, Michigan. Ten #14
reinforcement bars 8 ft (3.1 m) long were used in each CMB
section to transfer the design loads from the steel gate to the
CMB section. The #14 reinforcement bars were located in the part
of the CMB section that was closest to the steel gate. The last
3 in. (7.6 cm) of the top eight #14 bars was threaded so that the
reinforcement bars could screw into the rebar flange couplers.
The last 8 ft (3.1 m) of the concrete median barrier before the
gate had different shaped stirrups and a different cross
sectional geometry from that used in the standard CMB cross
section.
The steel tubes had a 3.5 in.
them at each end for the pins.
(8.9 cm) diameter hole cut in
Both of these holes were
reinforced with a 3.5 in. (8.9 cm) diameter schedule 40 steel
pipe sleeve insert. The main tubes also had a short steel tube
insert welded inside them at each end. The inserts were designed
to reduce the potential for the pins to fail the tubes. The 1.38
in. (3.5 cm) vertical gap between the beams was kept constant
over the length of the tubes by steel straps that were welded
onto both sides of the tubes. These straps helped the two
separate tubes to act as one unit and facilitated the mounting of
the W-beam on both sides of the tubes. End shoes were used with
11
the W-beams to reduce the snagging potential of the system. The
CMB part of the system was held in place by 1.25 in. (3.2 cm)
diameter anchor rods driven 6 to 8 in. (15.2 to 20.3 cm) into
the pavement. There were eight anchor rods in each CMB section.
The rods were separated by a center-to-center spacing of 6.5 ft
(2.0 m) and the rods were angled toward the center of the CMB at
approximately 45 degrees.
There were three features included in the design of the EOS
to facilitate the opening and closing of the gate by the
emergency vehicle operator. The first feature was a top mounted
jack and caster assembly manufactured as a single unit by Holland
Hitch Inc. of Holland, Michigan. The system was designed to open
into the bus lane at one end only, thus requiring one jack and
caster mechanism. The second feature consisted of two sets of
vertical 1 in. (2.5 cm) diameter rods. One rod was welded in
the end of the tubes and the other rod was inserted through a
hole cut in the tongue plates. The emergency vehicle operator
could then wrap a cable or chain around the rods and pull the
gate shut with the emergency vehicle. The final feature was the
vertical clearance between the beams and the tongue plates, and
the slotted holes cut in the tongue plates.
Tests were conducted after the EOS was fabricated to
demonstrate the amount of time required to open and close the
steel gate by an emergency vehicle operator. The complete EOS
tested was 90 ft (27.4 m) long and cost approximately $19,300.
The cost included two 30 ft (9.1 m) long modified CMB sections.
At a cost of $215/ft ($705./m), the barrier is reasonably priced
when compared to other alternatives. The average cost of
12
repairing the EOS after three full-scale crash tests was
approximately $2440. This value includes the cost to replace the
downstream CMB section after the third test.
13
CRASH TEST RESULTS
Three full-scale crash tests were conducted on the EOS as
shown in Figures 1 and 2. The tests conducted were designed to
evaluate the limits of performance of the barrier. The vehicle
impact point for test 1 and for test 3 was 6 ft (1.8 m) upstream
from the downstream end of the gate system. This point of impact
should cause the maximum forces on the CMB anchorage system, and
the maximum forces on the steel gate to the CMB section
connection. In addition, this impact point should give the
greatest possibility of vehicle snag on the barrier. The impact
point for test 2 was 6 ft (1.8 m) upstream from the midpoint of
the gate. This point of impact should cause maximum beam
deflections and maximum forces in the beam. The tests are
summarized in Table 1. Data acquisition systems are described in
Appendix A. Sequential photographs of the tests are given in
Appendix B. Appendix C shows accelerometer traces and plots of
roll, pitch, and yaw angles.
~l.
In the first test, an 1800 lb (815 kg) Honda Civic 1200
(1977) impacted the EOS 6 ft (1.8 m) upstream from the downstream
end of the steel gate system at 55.2 mph (88.8 km/h) and 15
degrees. Figure 4 contains a summary of this test. The test
vehicle was smoothly redirected. The vehicle exit angle and
speed were 5.5 degrees and 48.0 mph (77.3 km/h), respectively.
The occupant impact velocities were 14.15 ft/sec (4.31 m/s)
longitudinal and 16.42 ft/sec (5.00 m/s) lateral. The peak 50 ms
14
TABLE 1. SUMMARY OF CRASH TESTS
Test 1 2 3
Vehicle Weight, lbs (kg) 1800 (815) 4500 (2040) 4500 (2040)
Impact Speed, mph (km/h) 55.2 (88.8) 60.7 (97.7) 60.04 (96. 6 l
Impact Angle, degrees 15.0 25.25 25.5
Exit Speed, mph ( km/h) 48.0 (77.3) 47.96 (77.2) 39.01 (62.8)
Exit Angle, degrees 5.5 4.0 1.75
Maximum Beam Deflection, Dynamic, in. (cm) 3.36 ( 8. 53) 17.16 (43.59) 30.84 (78.33)
Permanent, in. (cm) o.o 1.63 (4.14) 23.88 (60.66)
Maximum CMB Movement Dynamic, in. (cm) 2.04 (5.18) 15.12 (38.40) 31.68 (80.47)
Permanent, in. (cm) o.o 3.75 ( 9 • 53) 24.00 (60.96)
Maximum CMB Roll, degrees o.o 3.5 9.0
Maximum CMB Yaw, degrees o.o o.o 5.5
Occupant Impact Velocity Longitudinal,ft/sec (m/s) 14.15 (4.32) 18.89 (5.76) 25.62 (7.81)
Lateral, ft/sec (m/s) 16.42 (5,00) 22.77 (6.94) 20.54 ( 6. 26)
Vehicle Accelerations, g's Occupant Ride Down
Longitudinal 1.49 8.21 4.11
Lateral 10.83 7,78 6.99
Peak 50 ms Average, g's
Longitudinal 4.27 5.77 8.59
Lateral 7.52 9.32 8.32
Vehicle Damage Classification
TAD 10LFQ4 11LFQ5 11FL6
VDI 10LFEW3 11LDEW4 11FDAW6
15
0.288 sec 0.193 sec
30 ft 6 ft
Test Number Test Date Vehicle
t-bdel tlass, lb (kg)
Speed, mph (km/h) Impact Exit
Angle, degrees Impact Exit
tlaximum Beam Deflection Dynamic, in (cm)
tlaximum OB t-bvement Dynamic, in . (cm)
0999-1 9-5-83
Honda Civic 1200 (1977) 1800 (815)
55.2 (88.8) 48.0 (77 . 3)
15.0 5.5
3. 36 (8.53)
2. 04 (5.18)
24 ft
0,0143 sec
30 ft
Occupant Impact Velocity, ft/s (m/s) Longitudinal Lateral
Vehicle Accelerations, g's Occupant Ride Down
Longitudinal Lateral
Peak 50 ms Average Longitudinal Lateral
Vehicle Damage Classification TAD VOI
Figure 4. Surrmary of Test 1.
0,048 sec
>I
14.15 (4.32) 16.42 (5.00)
1.49 10.83
4.27 7.52
10LFQ4 10LFEW3
average acceleration was 4,27 g's longitudinal and 7,52 g's
lateral, All of the occupant risk values as well as the vehicle
trajectory hazard are below recommended values (~) for this type
of test.
17
The test vehicle before and after the test is shown in
Figure 5.
the test.
Figure 6 shows the test installation before and after
Damage to the vehicle occured when the W-beam
corrugation dragged the front bumper down and the left front tire
snagged on one corner of the downstream CMB section. The vehicle
damage consisted of sheet metal damage to the left front fender,
the left front tire was flattened and the left front tire rim was
bent from the impact with the CMB. Damage to the EOS consisted
of the paint being scraped off the W-beam at the impact point and
some surface cracking in the downstream end of the CMB. The only
repairs to the gate were repainting the W-beam at the impact
point. The EOS was still operational after this test. This test
was considered a success based on the barrier safety performance
and the relatively light damage incurred by the system.
Tu§.t 2.
Test 2 examined the strength of the gate system. In this
test a 4500 lb (2040 kg) Plymouth Grand Fury (1977) impacted the
EOS 6 ft (1.8 m) upstream from the midpoint of the steel gate at
60.7 mph (97.7 km/h) and 25.25 degrees. Figure 7 contains a
summary of this test. The test vehicle was smoothly redirected.
The occupant impact velocities were 18.89 ft/sec (5.76 m/s)
longitudinal and 22.77 ft/sec (6.94 m/s) lateral. The vehicle
exit angle was 4 degrees and the vehicle exit velocity was 47.96
mph (77.2 km/h). The peak 50 ms average acceleration was 5.77
g's longitudinal and 9.32 g's lateral. The vehicle accelerations
were within acceptable limits (~) for this type of test. The
longitudinal occupant impact velocity was also within acceptable
13
I f
Fi gure 5 . Test Vehicle Before and After Test l .
19
Figure 6. Test Installation Before and After Test 1.
20
Figure 6. Test Ins ta 11 at ion Before and After Test 1 (continued) .
21
N N
CJ . 491 sec
4.07r----cm I I "
Test Number Test Date Vehicle
30 ft CM! SECTION
0. 328 sec
~ I" 21 ft
0999-2 9-7-83
llodel Plymouth Grand Fury {1977) fie.SS, lb (kg)
Speed , mph (km/h) Impact Exit
Angle, degrees Impact Exit
flaximum Beam Deflection, in . (cm) Dynamic Permanent
flaximum CMl Roll, degrees
4500 (2040)
60.7 (97 . 7l 47.96 (77.2
25.25 4. 0
17.16 (43 . 59) 1.63 (4.14)
3. 5
0. 246 sec
9 ft>- I o( 30 ft GA.TE SECTION CM! SECTION
flaximum CM! llovement, in. (cm) Dynamic Permanent
Occupant Impact Velocity, ft/s (m/s) Longitudinal Latera 1
Vehicle Accelerations, g' s Occupant Ride Down
Longitudinal Latera l
Peak 50 ms Average Longitudinal Lateral
Vehicle Damage Classification TAD VDI
Figure 7. SuT1111ary of Test 2.
0. 083 sec
15.12 (38.40) 3.75 (9.53)
18.89 (5.76) 22 .77 (6. 94)
8. 21 7. 78
5. 77 9.32
11LFQ5 11LDEW4
limits, but the lateral occupant impact velocity exceeded the
recommended value. Although the lateral occupant impact velocity
for this test exceeded the recommended value, it was less than
the limiting value. In addition, this type of test was not
required to meet the NCHRP criteria.
Figure 8 shows the damage incurred by the test vehicle. The
damage to the test installation is shown in Figure 9. The
vehicle damage consisted of sheet metal damage to the left front
fender. Damage to the EOS included the W-beam on the vehicle
impact side of the gate having to be replaced and noticeable
flexural cracking in the CMB sections. The permanent beam
deflection was 1.63 in. (4.1 cm). The gate could still be opened
after this test. This test was considered very successful based
on the safety performance of the system.
23
.. Figure 8. Test Vehicle Before and After Test 2.
24
---
...,,,,,,, 7 -- ....-_ __::.---___ - -~
Figure 9. Test Installation Before and After Test 2.
25
. .
Figure 9. Test Installation Before and After Test 2 (Continued).
26
~l
Test 3 examined the strength of the beam to CMB connection.
In this test a 4500 lb (2040 kg) Plymouth Grand Fury (1977)
impacted the EOS 6 ft (1.8 m) upstream from the downstream end
of the steel gate system at 60.04 mph (96.6 km/h) and 25.5
degrees. Figure 10 contains a summary of this test. The test
vehicle was smoothly redirected. The vehicle exit angle was 1.75
degrees and the vehicle exit speed was 39.01 mph (62.8 km/h).
The occupant impact velocities were 25.62 ft/sec (7.81 m/s)
longitudinal and 20.54 ft/sec {6.26 m/s) lateral. The peak 50
ms average acceleration was 8.59 g's longitudinal and 8.32 g's
lateral. The vehicle accelerations were within acceptable limits
(i) for this type of test. The lateral occupant impact velocity
was also within recommended limits, but the longitudinal occupant
impact velocity exceeded the recommended value. Although the
longitudinal occupant impact velocity for this test exceeded the
recommended value, it was less than the limiting value. In
addition, this type of test was not required to meet this
criteria.
Figure 11 shows the damage incurred by the test
The damage to the test installation is shown in Figure
vehicle.
12. The
test vehicle was severely damaged in this test when the vehicle
snagged on the downstream CMB section. The permanent deflection
of the gate was 23.88 in. (60.66 cm). Damage to the gate section
consisted of the W-beam on the impact side of the tubes having to
be replaced. The downstream CMB section was severely damaged due
to flexure cracking and when one of the anchor rods failed the
concrete. The upstream CMB section was also severely damaged due
27
N CXl
0.573 sec 0.382 sec 0.285 sec 0.094 sec
~
us'/ --<- /I 0,':0 f 1
~:j 25.s' T' : ~ I
r1,~~~~~~~~~~~~)~1~~~~~~l,~~~~~~~~~,~1~('--~~~~~~~~~---'l~~I 30 ft 6 ft 30 ft 30 ft CM3 SECTION GA.TE SECTION CM3 SECTION
Test Number Test Date
0999-3 Miximum CM3 M.:>vement, in. (cm) 9-9-83 Dynamic
Pennanent Vehicle t-bdel Miss, lb (kg)
Speed, mph (km/h)
Plymouth Grand Fury (1977) 4500 (2040)
Occupant Impact Velocity, ft/s (m/s) Longitudinal
Impact Exit
Anlge, degrees Impact Exit
Miximum CM3 Roll, degrees Miximum CM3 Yaw, degrees Miximum Beam Deflection, in.
Dynamic Permanent
(cm)
60.04 (96. 6) 39.01 (62.8)
25.5 1. 75 9.0 5.5
30.84 (78.33) 23.88 (60.66)
Lateral Vehicle Accelerations, g's
Occupant Ride Down Longitudinal Lateral
Peak 50 ms Average Longitudinal Lateral
Vehicle Damage Classi f i cation TAD VDI
Figure 10. Summary of Test 3.
31.68 (80.47) 24.00 (60.96)
25.62 (7.81) 20.54 (6.26)
4.11 6.99
8.59 8.32
11FL6 11FDAW6
Figure 11 . Test Vehicle Before and After Test 3.
29
Figure 12. Test Installation Before and After Test 3.
30
Figure 12. Test Installation Before and After Test 3 (Continued) .
31
Figure 12. Test Installation Before and After Test 3 (Continued) .
32
to flexural cracking. In addition, the gate could not be opened
due to the metal tubes binding about the pin connections.
However, this test was still considered a success based on the
barrier's safety performance and because the vehicle did not
penetrate the barrier.
33
SUMMARY AND CONCLUSIONS
An emergency opening system (EOS) for an authorized vehicle
lane (AVL) was developed and crash tested. The system, as shown
in Figures land 2, consisted of two steel box tubes mounted on
top of each other. The beams were supported by pins at the ends
that were connected to modified concrete median barrier sections.
Factors considered in its development were ease of operation and
ability to redirect errant vehicles.
Three full-scale crash tests were conducted to evaluate the
impact behavior of the design. In the first test, a small
vehicle was smoothly redirected. In test 2, a large vehicle was
smoothly redirected. In the third test a large vehicle was
redirected. All of the vehicle accelerations were below
recommended values for all of the crash tests. In addition, all
of the occupant impact velocities were within acceptable limits
for all of the crash tests except for the lateral occupant impact
velocities for tests 2 and 3. Although the lateral occupant
impact velocities for tests 2 and 3 exceeded the recommended
value, they were less than the limiting value. Futhermore, this
type of test was not required to meet this criteria. In addition,
the EOS was still operational after the first two tests. The
system was not operational after the third test because the
anchorage system for the downstream concrete median barrier
failed.
Several modifications in the design of the EOS were
34
recommended to improve the operation of the system. These
changes resulting from observations of the construction and crash
testing of the system can be seen in Figure 13. The differences
in the designs are listed as follows:
1. The concrete in the CMB below the steel mounting plates
should be rounded to reduce the snagging potential of
the EOS.
2. The stirrups in the transition section of the CMB should
be increased in size from 14 reinforcement bars to iS
reinforcement bars, and the spacing between the
stirrups should be increased to 3 in. (7.62 cm) center
to-center. The 114 reinforcement bars should have more
horizontal clearance between them. This increased
clearance will allow State Department of Highways and
Public Transportation (SDHPT) Class-c concrete (2) to be
used in the fabrication of the CMB.
3. The height of the concrete median barrier should be kept
constant at 32 in. (81.3 cm) to accommodate the
increased gap between the steel tubes.
4. The 114 reinforcement bars should be extended further
into the standard CMB shape to transfer more of the load
past the anchorage system. These reinforcement bars
should not all be cut off at the same location.
5. The fabricator of the concrete median barrier must place
the flange couplers exactly where the plans dictate,
and he must be certain that the concrete face used to
mount the base plate is vertical with respect to the
horizontal ledge.
35
C.> C)
\ ' PIVOT ENO SUPPORT ···,
~ PLATES-SEE DETAIL '-\ '---5• x 22 112· x7t8" STL P~,)
3 1/2"x22 1f2"x7!8" PL. --
PLAN ~
//
5'-3"
23'-0"
6'-3•
2-S"x8'x3/8"x28'-10" STL TUBES ASTM A500 GRADE B
'
6'-3" 5'-3"
" C3x6 STEEL CHANNELS ASTM A36•7" LONG
112" CLEAR ON EA CASING
__ 3'-4' -+ -2·-g· .J:.
'
- -5"x221/2"x718" STL. PL.
'QPENING EN:! SUPPORT Pl.A TES SEE DETAIL
3 1!2"x22 112"x718" STL. PL.
\ 31/2"x221/2"x 718"STL. PL 'LOWERABLE CASTER PIVOT C3x6 STEEL CHANNEL- '-SECLRE PIN - SEE DETAlL
PIVOT PW-SEE CETAIL
~-CONCFETE BARRER
8.EVATION
---0
a•xa"x318' STL. TLBE
LONGITUDINAL SECTION I i z-:::
1'--0" 2'-0"
Fi~1ure 13.
JACK/CASTER-SEE NOTES AT DETAIL A-A
".3 112"x22 1/2" x7/8' STL. PL
TEXAS TRANSPORTATION INSTITUTE THE TEXAS A&M UNIVERSITY SYSTEM
Design 11odifications for Eniergenc.:1 Onening S;,ster.L
'
,,.
'1 II 3/4"
1"" ,· 3 112· ,,. 6 112· 10"
2.5" ,· ,2.5"
I ~ •• I
" ',, ------- -o ~ I -- " '" E70XX ~ , rs
t - - - - -I
NOTE ALL EXPOSED EDGES OF SIDE PLATES ---ARE TO BE BEVELED AT 45° . ;,, I --· M
~·xs'x318' STL. Tl.BE - --- f--- 112' .
+ --- '-...E 70XX ~
BOLT HOLES-SEE DETAIL ON
I/ 11!• ;, ""
,,/ TttlS SHEET FOR SIZE AND SHAPE
------ ,---' M ::::1 I ' " ' 0/, INSERT C3x6 STEEL CHANNEL ------ ,_
ASTM """ r-- 1/,
t NOTE 718" PlA TE AT EITHER SIDE - ~-- - + REFER TO PLAN TO DETERMINE 1---- ~ I LOCATION & S!ZE ·~ --- e - ~-- - 1/r + HAND CRANKED JACK W(CASTER ASSEMBLY
.:::,e1oxx I
CRANK MAY BE TOP MOUNTED AS MANUFACT\.IEO BY HOLLAND HITCH CO.,
/ 1/2' ;, ~ REQUIRING ACCESS TO JACK P.O. BOX 3015, 430 W. 18Tii ST., HOLLAND, THROUGH BEAM_ JACK HANDLE ML 49423. JACK TO BE ABLE TO LFT 50()04>
' ------ -f ~ NOT TO PROTRUDE INTO TRAFFIC ~ VERTICAL 2-3 INCtES HOLLAND HITCH OR LANE WHILE NOT IN USE APPROVED EOUAL IJS-300-- JS-300-J &
ELEVATION sr SECTION A-A V-300-JS 6• DIA. CASTER
12.5" ,· ,.. MINIMUM REQUIRED. CASTER MUST BE FIXED
5\22112"•716" STL SO THAT IT WILL NOT ROTATE 36()
0.
PL ~-~ I ,,.~ END ELEVATION 0 3• 6. 1·-0·
I
2'-o"
H"'. A _.,...E70)0( /io· 6 112' '11/16"
' ~ I
,· ROO e, • so,~·· I NOTE GA TE SHOWN IN OPEN
I POSITION
0 1/2" r / '\ w 1 314" DIA. BOLT HOLE I ) ' • TO ACCOMMOOA TE 8"K8" STL. TUBE
22 112· K 3 112· x7/a· STL. PL 8-1 1/2" DIA. ASTM .. I, I , A490HS BOLTS K 4• 114" SHIM Al
0 LONG SIDE ANO BOTTOM 7"K7.x3/8•x13• STL TOOE WELDED ,. w
" INSIDE 8"x8" STL TUBE WI 114" SHIM PLATES AT SIDE AND BOTTOM
PLAN 31/2" l 22 112• STL.PL. BOLT HOLE (1/4"x7"x13")
114" CHAMFER AT ALL CORtERS SIZE AS MOTED
DETAILS AT END SUPPORTS SECTION B-B
---- ._==s GENERAL NOTES 0 ,· ,. 1·-0· 2·-0·
ALL STEEL TO BE ASTM A572 GRADE 50 w- I UNLESS OTHERWISE SPECIFIED 0 ,· ,· 1'-0" 2'-o"
PROVIDE BOTr! PINS (3 114" DIA. &. 3/4" DIA.) AT BOTH ENDS
ALL WELDS E70XX ELECTRODES
TB:XAS TRANSPORTATION INSTITUff THB: Tl:XAS A&II UNIYB:RSITY SYST•M
AUTHORIZED VEHCLE LANE EMERGENCY OPENING SYSTEM
IMPROVED DESIG~OPENING STEEL GA TE
o,IAIO'N .. ,0.11.9 I .,..,..,, Jllll. 19U !SHEET_, ._,,l'ED .. , IU.11 J lfE"'SIOlfDATE,OCTOIIEll.19U I 2 of•
Figure 13. Design t1odifications for Emergency Opening S~1stem. (continued)
w w
30·-o· r r----- 25'_::-1 314"
I
ELEVATION
UPSTREAM TRANSITION SECTION
" ,· I,. ,· 5/8" ~-
6'-4 1/4"
---'i"f+ r D(>
I .1 .1 -
-, . I
i ·' 1 -': ' -
I -. "'i IT f-----------:-:~8.25
I •' ' ,.,. ~
,,),,4· ! . "t I I
D '-.
ELEVATION
DOWNSTREAM TRANSITION SECTION RIGID ANCHOR OF CONTRACTOR DESIGN
ENGltEER APPROVED AT LOCATIONS SHOWN
SECTION (TYPICAL) NOTE: AS #14'$ ENO CONNECT .,.4 BARS
WITH APPROVED LAPPING AND TYING
olJ'w-- pll-iioj 4' a•
-
I
'"''
0.5" CHAIN'ER ALL CORt£RS
-- - ----
0.5" OiAIN'ER ALL CORNERS
(C - - ---- -- ------
56.26' 2·- , 10 13116"
.... <c
30·-o·
23'-5314" STANDARD CMB SHAPE
ELEVATION
I l --t
PLAN
I 'I> i
,1> ELEVATION
IMPROVED DESIGN -CONCRETE BARRIER
1~ __ ,._•.;_•_•·_o•_• __ l-lo;._•..:~_-':.:~;..':_· '.;.":.:' __ ___,lsHEET_,.; A-ono ev, K.E.R I REvis,o" oATE· ocrna•~ 1vn I 3 of 4
Figure 13. Desi,n r1odifications for E"1ergency Opening Systeci. (continued)
w <:)
NOTE: SHADED BARS TO BE TERMIMNATED WITH A FLANGE COUPLER
__ -10-.,.14 BARS GRADE 60
+-
; - .,.5 STIRRUPS
---+-- CONCRETE (SHADED)
'§..,f,~""'~s;;;;),~fB NOTE: WHERE 4'14 BARS END
_____ 13s1~~ s· ! J ~---"" __ ,_· ----::J
.!. CONNECT .,,.4 BARS WITH ENGINEER APPROVED LAPPING AND TIES
UPSTREAM END SECTION C-C
0 3• 6" ,·-a·
,.,
8 4'4 BARS
" 1 112• CLR I 1/4
' ,,, I
-!
"'4 BARS ~ '" j';:,
+-- ----
el I '
l~---~=F"~ I
~---___ i_,::,s,s· ~ L--- 2·-3_,_,._· ___ _
SECTION E-E
---0 3• 6° 1'-0"
,,. ,· 3 112· ,· A·,112· 1112· 5• 1112'
dn Nr ~ . '
-t--f<---t--t-c.,
,,.5 STIRRUP INSIDE DIA.
OF ALL BENDS IS 2.0" - ., N I
' = . ~1 ~' ,
I
!/l~ ' I! ~-~ "5 GRADE 60 CLOSED
·"~ ,.
3 112,
. ,, l..J.-----:-, ,· ,,.1 ,. _J 3 112·
l STIRRUP BEND AS SHOWN---~---"~-'~4-L
STIRRUP DETAIL FOR SECTION C-C
DOWNSTREAM END SECTION D-D
STJRRUP DETAIL FOR SECTION D-D
NOTE: SHADED .. 14 BARS (SEE SECT.C-C & D-0)
TERMINATED BY REBAR FLANGE COUPLER, WILLIAMS FORM-
,. ,4 BAR GRADE 60
FORM ENGINEERING CORP. GRAND RAPIDS, MICHIGAN, OR
SIMILAR PRODUCT REBAR IS THREADED INTO 3' OF COUPLER
FLANGE COUPLER IS BOLTED OR NAILED TO FORM FOR
FABRICATION END OF REBAR IS THREADED TO FIT FLANGE
COUPLER LAST 3" OF REBAR IS THREADED 1 112" DIA. a 6NC -- ----,--------..--i--, ... ' - -----+-- --
' _____ J-.----+--~ I
l FLANGE COUPLER --
,·
FLANGE COUPLER liiirl"5i2"!---:
0 ,·
NOTE: ALL CONCRETE SHALL BE CLASS "C" IN THE LATEST
EDITION OF SDHPT SPECIFICATIONS ALL REINFORCEMENT IS GRADE 60
NOTE: STIRRUP SPACING FOR HINGED END AND LATCHED END SECTIONS ARE TYPIC,1,L
NOTE: REGARDLESS OF METHOD OF HANDLING. BARRIER
SECTION LIFTING POINTS SHALL BE 6.25 FT. FROM THE
1· o·
TEXAS TRANSPORTATION INSTITUTE THE TEXAS AAM UNIVERSITY SYSTEM
AUTHORIZED VEHICLE LANE EMERGENCY OPENING SYSTEM
IMPROVED DESIGN-CONCRETE BARRIER
ENDS OF THE BARRIER. LIFTING DEVICES AND ATTACHMENTS ~----'-'_·•-'-'--1-"-'-"-'"-'-'·-'-"-'----lSHEHll:JWIEII TO BARRIER SECTION SHALL BE APPROVED BY THE ENGINEER A""'°\IEO Ir: H .•. R flEV/S,011 OA rE: OCTOBER, ..... 4 of 4
. Figure 13. Design i1odifications for Emergenc;, Opening Syster:1 . (continued)
6. The vertical concrete face used to mount the tongue
plates should have its width increased from 10 in. (25.4
cm) to 12 in. (29.5 cm).
7. The traffic side of the upstream concrete median barrier
should keep the same shape and reinforcement as the
typical CMB section in the transition part of the EOS.
8. A different anchorage system should be used to anchor
the CMB sections to the roadway surface.
9. The W-beams, end shoes and the side straps used to mount
them should be left off the side of the box beams to
reduce the snagging potential of the EOS. C3X6 steel
channels should be used between the tubes in place of
the steel side straps to keep the vertical
clearance between the beams constant.
10. A larger diameter and wider caster should be used
the jacks to facilitate opening and closing the
The caster should be fixed so that it will not
with
EOS.
rotate
360 degrees but will roll only back and forth across the
roadway.
11. The pin holes in the tongue plates should be increased
to 4 in. (10.2 cm) wide by 5 in. (12.7 cm) long to make
it easier to open and close the gate.
12. The holes in the base plates for the anchor bolts that
screw into the rebar flange couplers should be changed
from slotted holes to 1.75 in. (4.4 cm) diameter holes.
The bolt holes should be located as shown in Figure 13.
13. The vertical clearance between the steel tubes should be
40
increased to 3 in. (7.6 cm) to make it easier to open
and close the EOS.
14. The pipe sleeve inserts in the tubes should be increased
in size to 4 in. (10,2 cm) diameter schedule 40 steel
pipe.
15. The pins
longer to
used to operate the system will have to be
take into account the increased distance
between the tubes.
16. A jack and caster mechanism should be used at both ends
of the tubes so that the gate can be opened at either
end,
17. The side mounted plates on the tongue plates will have
to be arranged differently so that the gate can open
into the authorized vehicle lane from either end, yet
not open into the freeway traffic lanes, In addition,
the tongue plates and the base plate that the
tongue plates are welded to should have their width
increased from 8 in. (20,3 cm) to 10 in. (25,4 cm),
18. The handles on the pins should be built so that they can
be laid flat rather than sticking up in the air when
they are not needed to raise or lower the pin.
The full-scale crash tests showed that the system tested can
be used by an emergency vehicle to gain immediate access to an
authorized vehicle lane. In addition, the tests showed the
barrier's safety performance characteristics. Finally, the
ability of the steel gate to be opened and closed from either end
will allow the EOS to be used on any highway system that is
separated by concrete median barriers.
41
APPENDIX A
DATA ACQUISITION SYSTEMS
42
Instrumentation
Test vehicles were equipped with triaxial accelerometers
mounted near the center of gravity. Yaw, pitch and roll were
sensed by on-board gyroscopic instruments. The analog signals
were telemetered to a base station for recording on magnetic tape
and display on real-time strip chart. Provision was made for
transmission of calibration signals before and after the test,
and an accurate time reference signal was simultaneously recorded
with the data.
Tape switches near the impact area were actuated by the
vehicle to indicate elapsed time over a known distance to provide
a quick check of impact speed. The initial contact also produced
an "event• mark on the data record to establish the instant of
impact.
High-speed motion pictures were obtained from various
locations, including overhead, to document the events and provide
a time-displacement history. Film and electronic data were
synchronized through a visual/ electronic event signal at initial
contact.
43
\
APPENDIX B
SEQUENT! AL PHOTOGRAPHS
44
~· I • .........
0.000 sec
0.048 sec
0.095 sec
0.0143 sec
Figure 14. Sequential Photographs for Test 1.
45
0.193 sec
0.240 sec
0.288 sec
0.328 sec
Figure 14. Sequential Photographs for Test l.
46
(Continued)
0. 000 sec
0.163 sec
0.246 sec
Fi gure 15. Sequential Photographs for Test 2.
47
0.328 sec
0.409 sec
0.491 sec
0.579 sec
Figure 15. Sequential Photograpr.s for Test 2. (continued)
48
0.000 sec
0.094 sec
0.191 sec
0.285 sec
Figure 16. Sequential Photographs for Test 3.
49
0.382 sec
0.476 sec
0.573 sec
0.690 sec
Fi gure 16. Sequenti al Photographs for Test 3. (Continued)
50
APPENDIX C
ACCELEROMETER TRACES AND
PLOTS OF ROLL, PITCH, AND YAW RATES
51
z 0 -I-
10
5
0
~ -5 u..l -' u..l u u <l'.
-' <l'. z 8 -10 :::, 1--<.!! z 0 -'
-15
Class 180 Filter
1-----i,f--,- Max. 0.050 sec Avg. = -4.27 g
I
I !
I
I
I I I
I I !
I I I I
' I
I I I
I I
I'
'
'
I I I'
I I I I I
0.00 0. 10 0. 20 0.30 0.40
TIME (SECONDS)
Figure 17. Vehicle Longitudinal Accelerometer Trace for Test 1.
52
0. 50
....I < ,:,;
0
w -10 ,_ < _,
0.00
Class 180 Filter
0.10 0.20 0. 30 0.40
TIME (SECONDS)
Figure 18. Vehicle Lateral Accelerometer Trace for Test 1.
53
0.50
1 ·Z
~(ID'"~
0 0
lD
CCJNDSJ 0
0
u=;o 0 w.
WLD 0::: I
C)
w Do -o
0 1---z1 w ::,:: Wo LJO CI: •
lD _J-o_ I
(J)
>--<
Do 0
0 N
I
0 0
lD N
I
Axes are vehicle fixed. Sequence for determining orientation is:
1. Yaw 2. Pitch 3. Roll
Pitch
I 0.60
'Roll
Yaw
Figure 19. Vehicle Angular Displacement for Test 1.
54
201
I 10
Class 180 r·1 1 ter
~ . .·---,--- -
\ '\j. Max. a.050 sec -;--- -~
z 0 ~
I-
~ u.J ....J u.J
i I • . •o. • -,. 'i'I g
I : .. • I O rvtfrft-7t. W-1 ~ I • Ii
u u < ..J < z o -10 · .. · :::, I I-~
I I . . i I I . . '
-20 ;;;--0
~
1
~I-~~-~-o.oo 0.05 0.10 o. 15 0.20 0.25
TIME ( SECONDS)
Figure 20. Vehicle L . for Test o~g1tudinal Accel · erorneter T race
55
z 0
20
0
~ -20 "' ""' w __)
w u u
"' __)
"' cc -40 w I-
"' __)
-60 0.00
Class 180 Filter
Telemetry Fa i1 ure
Max. 0.050 sec Avg.= -9.3 g
0. C'S 0. 10 0.15 0.20
TIME (SECONDS)
Figure 21. Vehicle Lateral Accelerometer Trace for Test 2.
56
0.25
1 · z
~ •PtlCH ®YAW
g
0 0
Lf)
Eb 0
u=;o 0 w.
wlf) 0::: I
l'.)
w Do ~o
0 1--z1 w ::,:: Wo LJO a: .
Lf) __l-(LI
([) r-0
Do 0
0 (\J
I
0 0
Lf) (\J
I
,_
TIME .00
(SECONDS)
Axes are vehicle fixed. Sequence for determining orientation is:
l. Yaw 2. Pitch 3. Ro 11
Roll
Pitch
Yaw
Figure 22. Vehicle Angular Displacements for Test 2.
57
20
~
"" z: I 0 ' I - 0 I-cc "" u.J ..., u.J u u cc ..., cc
-20 z: -Cl ::::, I--"" z: 0 ...,
-40 0.00
Class 180 Filter
Max. 0.050 sec Avg.= -8.59 g
o. l O 0.20 0.30 0.40
TIME (SECONDS)
Figure 23. Vehicle Longitudinal Accelerometer Trace for Test 3.
58
0.50
20 j, 1 •
I I <!>
I I
z 0 ..... 0 I--
"" I er: LLI _,
I LLI u u I "" _,
I ~ -20 LL! . I I--
"" _, I I
-40 0.00 0. 10
Figure 24.
Class 180 Filter
Max. 0.050 sec Avg. = -8.32 g
0.20 0.30 0.40
TIME (SECONDS)
Vehicle Lateral Accelerometer Trace for Test 3.
59
0.50
0 0
0 -(f)O We() w . a::O
C)
w Do -o
0 1--Z' w :::;::: Wo LJO 0: . __J iG Q_ I
([)
>---<
Do 0
0 (f)
I
TIME SJ .OD 0.40
Axes are vehicle fixed. Sequence for determining orientation is:
1. Yaw 2. Pitch 3. Roll
Roll
0.60
itch
Yaw
Figure 25. Vehicle Angular Displacements for Test 3.
60
REFERENCES
1. Powell, Graham H., "Barrier VII: A Computer Program for
Evaluation of Automobile Barrier Systems,• Federal Highway
Administration, Washington, D. c., April, 1973.
2. "Building Code Requirements for Reinforced Concrete,• AC!
318-77, American Concrete Institute, Detroit, Michigan,
1977.
3. "Manual of Steel Construction,• American Institute of Steel
Construction, Chicago, Illinois, May, 1981.
4. Michie, Jarvis D., "Recommended Procedure for the Safety
Performance Evaluation of Highway Appurtenances,• NCHRP
Report 230, March, 1981.
5. •standard Specifications for Construction of Highways,
Streets and Bridges," Texas State Department of Highways
and Public Transportation,
1982.
61
Austin, Texas, September 1,