Emergency Opening System for an Authorized Vehicle...

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

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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

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42

44

51

61

LIST OF FIGURES

Figure~

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3

4

5

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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



Summary of Test 3



Design Modifications for Emergency Opening System

Sequential Photographs for Test 1



Vehicle Longitudinal Acceleration Trace for Test 1

Vehicle Lateral Acceleration Trace for Test 1

Vehicle Angular Displacement for Test 1


v

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10

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24

25

28

29

30

36

45

47

49

52

53

54

55

LIST OF FIGURES (continued)

Figure liQ...

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25






vi

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58

59

60

Table .HQ...

1

LIST OF TABLES

Summary of Crash Tests

vii

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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

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PLAN i:':'-0

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ELEVATION .::.. ..

LONGITUDINAL SECTION .. C:::S ,·

NOTE t. T Et.O '7' SHOE P'RO\ltx: W---t£1.M 12 GA SilV«)AA[) 1-1·x12"~12• Srt. p-..__ AT 25'-(l" HD.G STEEL ~& >J14·,1rx1e· Pl.. AT 1N""ERJ()fl El'() {1YPl9,1,.)

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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

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E1c1ergenC)' Ooenin:i S;•ster,1 for l\utl1orized Vehicle Lane,

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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 ---- -----

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UPSTREAM TRANSITION SECTION

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DOWNSTREAM TRANSITION SECTION

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SECTION (TYPICAL)

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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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DOWNSTREAM END SECTION D-0

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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

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AUTHORIZED VEHICLE LANE EMERGENCY OPENING SYSTEM

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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

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90'--{)"

30'-<l"

lFSTREAM TRANSITION SECTION DOUBLE 8" SQUARE TUBE GATE -O' 4'-o"

PLAN WITH GATE CLOSED

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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

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DOWNSTREAM TRANSITION SECTION

a• x8" x3/8" STEEL TUBE

INSERT C3x6 STEEL CHANN'.L ASTM A36

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:1.-...l~--Wl-TH FIXED CASTER

SECTK>N AT JACK/CASTER ASSEMBLY

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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.


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


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 -- ....-_ __::.---___ - -~


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).


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


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


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)


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


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,

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