NCHRP Report 350 Test 4-12 of the Massachusetts S3-TL4 ...The Massachusetts S3-TLA Steel Bridge...

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TEXAS TRANSPORTATION INSTITUTE NCHRP REPORT 350 TEST 4-12 OF THE MASSACHUSETTS S3-TL4 STEEL BRIDGE RAILING MOUNTED ON CURB AND SIDEWALK by C. Eugene Buth · Research Engineer and Wanda L. Menges · Associate Research Specialist Research Project 404251-3 Contract No. DTFH61-97-C-00049 Sponsored by U.S. Department of Transportation Federal Highway Administration July 1998 TEXAS TRANSPORTATION INSTITUTE THE TEXAS A & M UNIVERSITY SYSTEM COLLEGE STATION, TEXAS

Transcript of NCHRP Report 350 Test 4-12 of the Massachusetts S3-TL4 ...The Massachusetts S3-TLA Steel Bridge...

Page 1: NCHRP Report 350 Test 4-12 of the Massachusetts S3-TL4 ...The Massachusetts S3-TLA Steel Bridge Railing system is a beam and post system consisting of three tubular steel rail elements

TEXAS TRANSPORTATION INSTITUTE

NCHRP REPORT 350 TEST 4-12 OF THE MASSACHUSETTS S3-TL4 STEEL BRIDGE RAILING

MOUNTED ON CURB AND SIDEWALK

by

C. Eugene Buth · Research Engineer

and

Wanda L. Menges · Associate Research Specialist

Research Project 404251-3 Contract No. DTFH61-97-C-00049

Sponsored by U.S. Department of Transportation

Federal Highway Administration

July 1998

TEXAS TRANSPORTATION INSTITUTE THE TEXAS A & M UNIVERSITY SYSTEM

COLLEGE STATION, TEXAS

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TECHNICAL REPORT DOCUMENTATION PAGE

I. ReportNo. 2. Government Accession No. 3. Recipient's Catalog No.

FHW A-RD-98-4. Title and Subtitle 5. Report Date

NCHRP REPORT 350 TEST 4-12 OF THE July 1998 MASSACHUSETTS S3-TL4 STEEL BRIDGE RAILING 6. Performing Organization Code

WITH CURB AND SIDEWALK 7. Author(s) 8. Performing Organization Report No.

C. Eugene Buth and Wanda L. Menges 404251-3 9. Performing Organization Name and Address 10. Work Unit No.

Texas Transportation Institute NCPNo. The Texas A&M University System 11. Contract or Grant No.

College Station, Texas 77843-3135 DTFH61-97 -C-00049 12. Sponsoring Agency Name and Address 13. Type of Report and Period Covered

Federal Highway Administration Test Report U.S. Department of Transportation July 1997- July 1998 400 Seventh Street, S.W. 14. Sponsoring Agency Code

Washington, D.C. 20590

15. Supplementary Notes

Project conducted in cooperation with Federal Highway Administration. Research Study Title: Assessment of Existing Roadside Safety Hardware II Contracting Officer's Technical Representative (COTR): Charles F. McDevitt- HSR -20

16. Abstract

This report presents the details of the Massachusetts S3-TL4 Steel Bridge Railing mounted on curb and sidewalk and results of the test with the single unit truck: National Cooperative Highway Research Program (NCHRP) Report 350 test designation 4-12, which is the 8000-kg single-unit truck impacting the critical impact point (CIP) at 80 km/h and 15 degrees. The Massachusetts S3-TL4 Steel Bridge Railing mounted on curb and sidewalk met all requirements specified for NCHRP Report 350 test designation 4-12.

17. Key Words 18. Distribution Statement

Bridge railings, crash testing, roadside safety No restriction. This document is available to the public through National Technical Information Service, 5285 Port Royal Road, Springfield, Virginia 22161

19. Security Classif. (of this report) 20. Security Classif. (of this page) 21. No. of Pages 22. Price

Unclassified Unclassified 47

FormDOTF 1700.7 (8-69)

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APPROXIMATE CONVERSIONS TO Sl UNITS APPROXIMATE CONVERSIONS FROM Sl UNITS

Symbol When You Know

Multiply by To Find Symbol Symbol When You Know Multiply by To Find Symbol

LENGTH LENGTH

in inches 25.4 millimeters mm mm millimeters 0.039 inches in ft feet 0.305 meters m m meters 3.28 feet ft yd yards 0.914 meters m m meters 1.09 yards yd mi miles 1.61 kilometers km km kilometers 0.621 miles mi

AREA AREA

in 2 square inches 645.2 square millimeters mm' mm' square millimeters 0.0016 square inches in 2

ft 2 square feet 0.093 square meters m' m' square meters 10.764 square feet ft 2

yd' square yards 0.836 square meters m' m' square meters 1.195 square yards yd' ac acres 0.405 hectares ha ha hectares 2.47 acres ac mi 2 square miles 2.59 square kilometers km' km' square kilometers 0.386 square miles mi 2

VOLUME VOLUME

fl oz fluid ounces 29.57 milliliters ml ml milliliters 0.034 fluid ounces fl oz gal gallons 3.785 liters L L liters 0.264 gallons gal ft' cubic feet 0.028 cubic meters ms ms cubic meters 35.71 cubic feet ft3 yd3 cubic yards 0.765 cubic meters ms ms cubic meters 1.307 cubic yards yd3

....... Ill ....... NOTE: Volumes greater than 1 000 I shall be shown in m3

MASS MASS

oz ounces 28.35 grams g g grams 0.035 ounces oz lb pounds 0.454 kilograms kg kg kilograms 2.202 pounds lb T short tons 0.907 megagrams Mg Mg megagrams 1.103 short tons T

12000 lb) lor "metric ton") lor "t") lor "t") (or "metric ton") 12000 Ill)

TEMPERATURE TEMPERATURE

'F Fahrenheit 5(F-32)/9 Celcius 'C 'C Celcius 1.8C+32 Fahrenheit 'F temperature or temperature temperature temperature

(F-32)/1.8

ILLUMINATION ILLUMINATION

fc foot -candles 10.76 lux lx lx lux 0.0929 foot-candles fc fl foot-Lamberts 3.426 candela/m 2 cd/m2 cd/m 2 candela/m 2 0.2919 foot-Lamberts fl

FORCE and PRESSURE or STRESS FORCE and PRESSURE or STRESS

lbf poundforce 4.45 newtons N N newtons 0.225 poundforce lbf lbf/in' poundforce per 6.89 kilopascals kPa kPa kilopascals 0.145 poundforce per lbf/in'

square inch square inch

*SI is the symbol for the lnternattonal System of Units. Appropriate (Revised September 1993) rounding should be made to comply with Section 4 of ASTM E380.

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TABLE OF CONTENTS

I. INTRODUCTION .......................................................... 1

II. STUDY APPROACH ...................................................... 3 TEST ARTICLE ......................................................... 3 CRASH TEST CONDITIONS ............................................. 3 EVALUATION CRITERIA ............................................... 6 CRASH TEST AND DATA ANALYSIS PROCEDURES ....................... 7

Electronic Instrumentation and Data Processing ........................... 7 Anthropomorphic Dummy Instrumentation ............................... 8 Photographic Instrumentation and Data Processing ......................... 8 Test Vehicle Propulsion and Guidance .................................... 8

III. CRASH TEST RESULTS .................................................. 9 TEST 404251-3 (NCHRP Report 350 test no. 4-12) ............................. 9

Test Description ...................................................... 9 Damage to Test Installation ............................................ 17 Vehicle Damage ...................................................... 17 Occupant Risk Values ................................................ 17

IV. SUMMARY OF FINDINGS AND CONCLUSIONS ........................... 31 SUMMARY OF FINDINGS .............................................. 31 CONCLUSIONS ........................................................ 31

REFERENCES .............................................................. 33

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LIST OF FIGURES

Figure No. Page

1 Details of the Massachusetts S3-TL4 Steel Bridge Railing mounted on curb and sidewalk .......................................... 4

2 Massachusetts S3-TL4 Steel Bridge Railing mounted on curb and sidewalk before test404251-3 .................................................. 5

3 Vehicle/installation geometries for test 404251-3 ........................... 10 4 Vehicle before test 404251-3 ........................................... 11 5 Vehicle properties for test 404251-3 ..................................... 12 6 Sequential photographs for test 404251-3

(overhead and frontal views) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 7 Sequential photographs for test 404251-3

(close-up frontal and rear views) ........................................ 15 8 Afterimpacttrajectoryfortest404251-3 ................................. 18 9 Installation after test 404251-3 ......................................... 19

10 Vehicle after test 404251-3 ............................................ 20 11 Interior of vehicle for test 404 251-3 ..................................... 21 12 Summary of results for test 404251-3, NCHRP Report 350 test 4-12 ............ 22 13 Vehicle angular displacements for test 404251-3 ........................... 23 14 Vehicle longitudinal accelerometer trace for test 404251-3

(accelerometer located at center of gravity) ................................ 24 15 Vehicle lateral accelerometer traces for test 404251-3

(accelerometerlocated at center of gravity) ................................ 25 16 Vehicle vertical accelerometer trace for test 404251-3

(accelerometerlocated at center of gravity) ................................ 26 17 Vehicle longitudinal accelerometer trace for test 404251-3

(accelerometer located in front section of cab of vehicle) ..................... 27 18 Vehicle lateral accelerometer traces for test 404251-3

(accelerometer located in front section of cab of vehicle) ..................... 28 19 Vehicle longitudinal accelerometer trace for test 404251-3

(accelerometer located over rear axle) .................................... 29 20 Vehicle lateral accelerometer traces for test 404251-3

(accelerometer located over rear axle) .................................... 30

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LIST OF TABLES

Table No. Page

1 Performance evaluation summary for test 404251-3, NCHRP Report 350 test4-12 .......................................... 32

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I. INTRODUCTION

New roadside safety hardware is being designed and developed on a continuing basis due to specific needs or constraints of individual states. To assure that these new designs perform according to established guidelines, full-scale crash testing and evaluation are necessary. The objective of this study is to crash test and evaluate the Massachusetts S3-TL4 Steel Bridge Railing mounted on curb and sidewalk.

The Federal Highway Administration (FHW A) has adopted National Cooperative Highway Research Program (NCHRP) Report 350, Recommended Procedures for the Safety Peiformance Evaluation of Highway Features, as the official guidelines for performance evaluation of roadside safety hardware.(!) NCHRP Report 350 specifies the required crash tests for longitudinal barriers, such as bridge rails, for six performance levels as well as evaluation criteria for structural adequacy, occupant risk, and post-test vehicle trajectory for each test. The Massachusetts S3-TL4 Steel Bridge Railing mounted on curb and sidewalk was evaluated according to specifications of test level four (TL-4) of NCHRP Report 350.

For evaluation to TL-4, three full-scale crash tests on the length of need (LON) of the longitudinal barrier are required. These include an 820-kg passenger car impacting the critical impact point (CIP) at a nominal impact speed and angle of 100 km/h and 20 degrees, a 2000-kg pickup truck impacting the CIP at a nominal impact speed and angle of 100 km/h and 25 degrees, and an 8000-kg single-unit truck impacting the CIP at a nominal impact speed and angle of 80 km/h and 15 degrees.

This report presents the details of the Massachusetts S3-TL4 Steel Bridge Railing mounted on curb and sidewalk and results of the test with the single-unit truck: NCHRP Report 350 test designation 4-12, which is the 8000-kg single-unit truck impacting the CIP at 80 krnlh and 15 degrees. The Massachusetts S3-TL4 Steel Bridge Railing mounted on curb and sidewalk met all requirements specified for NCHRP Report 350 test designation 4-12.

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II. STUDY APPROACH

TEST ARTICLE

The Massachusetts S3-TLA Steel Bridge Railing system is a beam and post system consisting of three tubular steel rail elements mounted on steel wide flange posts bolted to the concrete deck/sidewalk. Total height of the rail from the top of the sidewalk to the top of the upper rail element is 1069 mm. The top rail is a TS127x102x6.4. The remaining two rail elements are TS127x127x6.4 and are mounted at 380 mm and 710 mm from the top of the sidewalk to the center of the rail elements. Posts are W150x37 and are welded to 32-mm thick base plate. The posts are bolted to the sidewalk with M27 ASTM A449M anchor bolts 300 mm long. A 16 mm x 260 mm x 300 mm anchor plate was tack welded to the heads of the anchor bolts.

The railing was mounted on a sidewalk with 1550 mm width on the traffic side of the railing. The curb face of the sidewalk was 200 mm in height. A 3650-mm wide unreinforced simulated deck surface was cast on natural grade on the traffic side of the sidewalk for the test installation. The sidewalk with a 760-mm overhang on the field side was cast on an existing concrete "foundation" and was anchored to the top of that foundation in the same manner that it would be anchored to a bridge beam in the field. Epoxy-coated reinforcing steel was used. The test railing installation was 23 m long. The bridge railing was terminated at each end with no guardrail or other structure installed. Post spacing was 2.0 m and vertical picket assemblies were installed on the field side of the longitudinal rail elements. Details of the Massachusetts S3-TLA Bridge Railing mounted on curb and sidewalk are shown in figure 1. The completed installation is shown in figure 2.

Standard concrete compressive strength cylinders were cast. Strength tests performed at 20 days age, on May 20, 1998, resulted in an average compressive strength of the sidewalk of 37.7 MPa.

CRASH TEST CONDITIONS

According to NCHRP Report 350, three tests are required to evaluate longitudinal barriers to test level four (TL-4 ):

NCHRP Report 350 test designation 4-10: An 820-kg passenger car impacting the critical impact point (CIP) in the length of need (LON) of the longitudinal barrier at a nominal speed and angle of 100 kmlh and 20 degrees. The purpose of this test is to evaluate the overall performance of the LON section in general, and occupant risks in particular.

NCHRP Report 350 test designation 4-11: A 2000-kg pickup truck impacting the CIP in the LON of the longitudinal barrier at a nominal speed and angle of 100 kmlh and

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~

--{'.-" -=----~-. -.----~-~~·· .. .-,..-~ ......... ===========··~=··=::.::.::::; .. ~ .. ~ .. :;:.=:;:;: ... ~ .. :;:;:. = .... ,,,.,,,., .. ,.,.,,.,.,,.,,., "'"-"'-"'·~"'·'·''''~"'····~••co·•~o ·'"-'''"···''··'•·•' .. ,._·c:c·~··cc· ~- ··~I

ITl

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~~-23,000~~~~~~~~~~~~~~~-j

===-l= .. ·•=cc==j

UNREINFORCED CONCRETE SI.AB

®~

38 x 38 1.6 thk. x 985 long PICKETS

25 MIN.

1 (TYP.)

L76x51x6.4 DETAIL

11 j(TYP.)] ,

DETAIL B

POST (f.

EFFECTIVE JOIN1 WIDTH + 15 AT BRIDGE EXPANSION JOINT (15 @ I O'C AT TYPICAL RAIL SPLICES)

W150x37 (NP.)

50 CL. ·4' 700 (SPLICE TUBE)

BRIDGI !'AILING ELEVATION (FIELD SIDE)

~~~~~~~1550--~~~~~~-­(Sidewalk Width)

~L] __ EXISTING FOUNDATION

NOTES: 1. FOR DETAILS NOT SHOWN, SEE

MASS. STANDARD DRAWING DATED JUNE 27,1997.

2. MIN. COMPRESSIVE STRENGTH OF CONCRETE SHALL BE 5000 PSI.

3. MAX. SIZE OF AGGREGATE SHALL BE 19mm.

4 MIN. YIELD STRENGTH OF REINFORCEMENT SHALL BE 60KSI

The Texas A&M University System

'""'''"" I I TEXAS TRANSPORTATION INSTITUTE Dolo '' COLLEGE STATION, TEXAS 77843

Scele

Figure 1 . Details of the Massachusetts S3-TL4 Steel Bridge Railing mounted on curb and sidewalk.

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Figure 2. Massachusetts S3-TL4 Steel Bridge Railing mounted on curb and sidewalk before test 404251-3.

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25 degrees. The test is intended to evaluate the strength of section in containing and redirecting the pickup truck.

NCHRP Report 350 test designation 4-12: An 8000-kg single-unit truck impacting the CIP in the LON of the longitudinal barrier at a nominal speed and angle of 80 kmlh and 15 degrees. The test is intended to evaluate the strength of the section in containing and redirecting the heavy truck.

The test reported herein (test 404251-3) corresponds to NCHRP Report 350 test designation 4-12. The CIP for this test was determined using information contained in Section 3.4 and table 3.12 ofNCHRP Report 350 and accordingly was 1.5 m upstream of post 6 of the Massachusetts S3-TL4 Steel Bridge Railing.

EVALUATION CRITERIA

The crash test performed was evaluated in accordance with the criteria presented in NCHRP Report 350. As stated in NCHRP Report 350, "Safety performance of a highway appurtenance cannot be measured directly but can be judged on the basis of three factors: structural adequacy, occupant risk, and vehicle trajectory after collision." Accordingly, the following safety evaluation criteria from table 5.1 ofNCHRP Report 350 were used to evaluate the crash test reported herein:

• Structural Adequacy

A. Test article should contain and redirect the vehicle; the vehicle should not penetrate, underride, or override the installation although controlled lateral deflection of the test article is acceptable.

• Occupant Risk

D. Detached elements, fragments or other debris from the test article should not penetrate or show potential for penetrating the occupant compartment, or present an undue hazard to other traffic, pedestrians, or personnel in a work zone. Deformation of, or intrusions into, the occupant compartment that could cause serious injuries should not be permitted.

G. It is preferable, although not essential, that the vehicle should remain upright during and after collision.

• Vehicle Trajectory

K. After collision it is preferable that the vehicle's trajectory not intrude into adjacent traffic lanes.

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M. The exit angle from the test article preferably should be less than 60 percent of the test impact angle, measured at time of vehicle loss of contact with the test device.

CRASH TEST AND DATA ANALYSIS PROCEDURES

The crash test and data analysis procedures were in accordance with guidelines presented in NCHRP Report 350. Brief descriptions of these procedures are presented as follows.

Electronic Instrumentation and Data Processing

The test vehicle was instrumented with three solid-state angular rate transducers to measure roll, pitch and yaw rates; a triaxial accelerometer near the vehicle center-of-gravity to measure longitudinal, lateral, and vertical acceleration levels, and a back-up biaxial accelerometer in the rear of the vehicle to measure longitudinal and lateral acceleration levels. The accelerometers were strain-gauge type with a linear millivolt output proportional to acceleration.

The electronic signals from the accelerometers and transducers were transmitted to a base station by means of constant bandwidth FMIFM telemetry link for recording on magnetic tape and for display on a real-time strip chart. Calibration signals were recorded before and after the test, and an accurate time reference signal was simultaneously recorded with the data. Pressure­sensitive switches on the bumper of the impacting vehicle were actuated just prior to impact by wooden dowels to indicate the elapsed time over a known distance to provide a measurement of impact velocity. The initial contact also produced an "event" mark on the data record to establish the exact instant of contact with the installation.

The multiplex of data channels, transmitted on one radio frequency, was received at the data acquisition station, and demultiplexed into separate tracks of Inter-Range Instrumentation Group (I.R.I.G.) tape recorders. Mter the test, the data were played back from the tape machines, filtered with anSAE 1211 filter, and digitized using a microcomputer, for analysis and evaluation of impact performance.

The digitized data were then processed using two computer programs: DIGITIZE and PLOT ANGLE. Brief descriptions on the functions of these two computer programs are provided as follows.

The DIGITIZE program uses digitized data from vehicle-mounted linear accelerometers to compute occupant/compartment impact velocities, time of occupant/compartment impact after vehicle impact, and the highest 10-ms average ridedown acceleration. The DIGITIZE program also calculates a vehicle impact velocity and the change in vehicle velocity at the end of a given impulse period. In addition, maximum average accelerations over 50-ms intervals in each of the three directions are computed. For reporting purposes, the data from the vehicle-mounted accelerometers were then filtered with a 60-Hz digital filter and acceleration versus time curves

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for the longitudinal, lateral, and vertical directions were plotted using a commercially available software package (Excel 7).

The PLOT ANGLE program used the digitized data from the yaw, pitch, and roll rate transducers to compute angular displacement in degrees at 0.00067-s intervals and then instructs a plotter to draw a reproducible plot: yaw, pitch, and roll versus time. These displacements are in reference to the vehicle-fixed coordinate system with the initial position and orientation of the vehicle-fixed coordinate system being that which existed at initial impact.

Anthropomorphic Dummy Instrumentation

The use of a dummy in an 8000S vehicle is optional. No dummy was used in this test with the 8000S vehicle.

Photographic Instrumentation and Data Processing

Photographic coverage of the test included three high-speed cameras: one overhead with a field of view perpendicular to the ground and directly over the impact point; one placed behind the installation at an angle; and a third placed to have a field of view parallel to and aligned with the installation at the downstream end. A flash bulb activated by pressure sensitive tape switches was positioned on the impacting vehicle to indicate the instant of contact with the installation and was visible from each camera. The films from these high-speed cameras were analyzed on a computer-linked Motion Analyzer to observe phenomena occurring during the collision and to obtain time-event, displacement and angular data. A 16-mm movie cine, a Betacam, a VHS­format video camera and recorder, and still cameras were used to record and document conditions of the test vehicle and installation before and after the test.

Test Vehicle Propulsion and Guidance

The test vehicle was towed into the test installation using a steel cable guidance and reverse tow system. A steel cable for guiding the test vehicle was tensioned along the path, anchored at each end, and threaded through an attachment to the front wheel of the test vehicle. An additional steel cable was connected to the test vehicle, passed around a pulley near the impact point, through a pulley on the tow vehicle, and then anchored to the ground such that the tow vehicle moved away from the test site. A 2 to 1 speed ratio between the test and tow vehicle existed with this system. Just prior to impact with the installation, the test vehicle was released to be free-wheeling and unrestrained. The vehicle remained free-wheeling, i.e., no steering or braking inputs, until the vehicle cleared the immediate area of the test site, at which time brakes on the vehicle were activated to bring it to a safe and controlled stop.

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III. CRASH TEST RESULTS

TEST 404251-3 (NCHRP Report 350 test no. 4-12)

A 1979 Chevrolet C70 single-unit truck, shown in figures 3 and 4, was used for the crash test. Test inertia weight of the vehicle was 8000 kg, and its gross static weight was 8000 kg. The height to the lower edge of the vehicle bumper was 550 mm and it was 870 mm to the upper edge of the bumper. Additional dimensions and information on the vehicle are given in figure 5. The vehicle was directed into the installation using the cable reverse tow and guidance system, and was released to be free-wheeling and unrestrained just prior to impact.

The test was performed on the morning of June 19, 1998. A total of 5 mm of rainfall fell eight days prior to the test. No other rainfall of significance occurred during the ten days prior to the test. Weather conditions the day of the test were as follows: Wind Speed: 19 kmlh; Wind direction: 15 degrees with respect to the vehicle (vehicle traveling southerly); Temperature: 33 oc; Relative Humidity: 55 percent.

Test Description

The vehicle, traveling at 79.6 kmlh, impacted the curb of the Massachusetts S3-TL4 Bridge Rail installation 2.18 m from the end at an impact angle of 15.1 degrees. Shortly after impact with the curb the right front tire turned slightly to the left and then began to climb up the curb. At 0.030 s the wheels turned to the right (toward the bridge rail) and then straightened. By 0.064 s the right front wheel reached the top of the sidewalk. At 0.211 s the right rear wheel contacted the curb. The right front corner of the bumper contacted the center rail element of the bridge rail at 0.281 s. Speed of the vehicle was 77.0 kmlh and the impact angle was 16.0 degrees. The right front quarter panel contacted the upper rail element at 0.291 sand the right front tire contacted the lower element at 0.294 s. Redirection of the vehicle occurred at 0.323 s. The lower front right corner of the box reached the top of the top rail element at 0.434 s. At 0.590 s the right rear tire contacted the lower rail element and the vehicle was traveling parallel with the rail at a speed of 73.6 kmlh. The box of the vehicle continued to ride on top the rail element and lost contact between post 9 and 10. The vehicle continued to the end of the rail traveling at an exit angle of less than 5 degrees. Brakes on the vehicle were applied at 2.5 s after impact with the curb. The vehicle subsequently came to rest 103.6 m down and 5.3 m behind the bridge rail. Sequential photographs of the collision period can be found in figures 6 and 7.

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Figure 3. Vehicle/installation geometries for test 404251-3.

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Figure 4. Vehicle before test 404251-3.

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... C.b.e.v.r.o.Le.-1 ..

-~··- ..... ____ 1_9~LiL~--~-~--

.l ..

. .. .!

.... 22~20 .. 54.80 .3 . .0 .. 9.7 .... 5 .. B.D.O ... : ~ :

. ___ .1..2.:Z.O_~~ c:::-:,-·-, ____ ,.._,_,.._; __ \...·~---····

.- ...... 5..2.30 .. _: .......... 1. .. 6.2 .. 0. .. . P .. =~ / '-'··

!.,! =·:;, .......... 2.5.5.8 ....

.. 800.0 ...

Figure 5. Vehicle properties for test 404251-3.

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0.000 s

0.098 s

0.390 s

0.537 s

Figure 6. Sequential photographs for test 404251-3 (overhead and frontal views).

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0.537 s

0.732 s

1.024 s

1.342 s

Figure 6. Sequential photographs for test 404251-3 (overhead and frontal views) (continued).

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0.000 s

0.098 s

0.244 s

0.390 s

Figure 7. Sequential photographs for test 404251-3 (close-up frontal and rear views).

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0.537 s

0.732 s

1.024 s

1.342 s

Figure 7. Sequential photographs for test 405651-3 (close-up frontal and rear views) (continued).

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Damage to Test Installation

Damage to the Massachusetts S3-TIA Bridge Railing mounted on curb and sidewalk is shown in figures 8 and 9. Tire marks and scrapes were on the three rail elements and the lower two elements were pushed downward 15 mm. Cracks on the top surface of the deck/sidewalk extended from the front bolts on post 6 and radiated rearward on the impact side for 220 mm to the edge of the deck/sidewalk and 590 mm on the opposite side to the rear edge of the deck/sidewalk. A crack from the center bolt on the impact side of post 6 radiated 350 mm to the edge of the deck/sidewalk and continued 300 mm down the field side face of the deck/sidewalk. Maximum deformation after the test was 10 mm to the middle rail element. Length of contact with the bridge rail was 8.6 m.

Vehicle Damage

The vehicle sustained minor damages on the front right and right side as shown in figure 10. Structural damage was received by the front springs, U-bolts, shocks and front axle. Damage was also received by the bumper, right front quarter panel, right rear outside tire and right front lug bolts. The fuel tank and straps were deformed. Maximum exterior crush to the vehicle was 114 mm and no deformation or intrusion into the occupant compartment occurred. The interior of the vehicle is shown in figure 11.

Occupant Risk Values

Occupant risk values are not required for this test, however, the values were computed and are reported for information only. In the longitudinal direction, the occupant impact velocity was 2.0 m/s at 0.681 s, the highest 0.010-s occupant ridedown acceleration was -1.9 g's from 0.696 to 0.706 s, and the maximum 0.050-s average acceleration -1.5 g's between 0.311 and 0.361 s. In the lateral direction, the occupant impact velocity was 2.6 m/s at 0.431 s, the highest 0.010-s occupant ridedown acceleration was -9.7 g's from 0.598 to 0.608 s, and the maximum 0.050-s average was -4.4 g's between 0.250 and 0.300 s. These data and other pertinent information from the test are summarized in figure 12. Vehicle angular displacements are displayed in figure 13. Vehicular accelerations versus time traces are presented in figures 14 through 20.

17

Page 25: NCHRP Report 350 Test 4-12 of the Massachusetts S3-TL4 ...The Massachusetts S3-TLA Steel Bridge Railing system is a beam and post system consisting of three tubular steel rail elements

Figure 8. After impact trajectory for test 404251-3.

18

Page 26: NCHRP Report 350 Test 4-12 of the Massachusetts S3-TL4 ...The Massachusetts S3-TLA Steel Bridge Railing system is a beam and post system consisting of three tubular steel rail elements

Figure 9. Installation after test 404251-3.

19

Page 27: NCHRP Report 350 Test 4-12 of the Massachusetts S3-TL4 ...The Massachusetts S3-TLA Steel Bridge Railing system is a beam and post system consisting of three tubular steel rail elements

Figure 10. Vehicle after test404251-3.

20

Page 28: NCHRP Report 350 Test 4-12 of the Massachusetts S3-TL4 ...The Massachusetts S3-TLA Steel Bridge Railing system is a beam and post system consisting of three tubular steel rail elements

Before test

After test

Figure 11. Interior of vehicle for test 404251-3.

21

Page 29: NCHRP Report 350 Test 4-12 of the Massachusetts S3-TL4 ...The Massachusetts S3-TLA Steel Bridge Railing system is a beam and post system consisting of three tubular steel rail elements

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03.6 rn-------·-

N General Information N Test Agency . . . . . . . . . . . Texas Transportation Institute

Test No ............... 404251-3 Date . . . . . . . . . . . . . . . . 06/19/98

Test Article Type . . . . . . . . . . . . . . . . Bridge Rail Name . . . . . . . . . . . . . . . . Mass. S3-TL4 on curb/sidewalk Installation Length (m) . . . . 23.0 Material or Key Elements . . Tubular Steel Rail Elements on Steel

Wide Flange Posts on Sidewalk Soil Type and Condition . . . . . Concrete Bridge Deck, Dry Test Vehicle

Type . . . . . . . . . . . . . . . . Production Designation . . . . . . . . . . . . 8000S Model . . . . . . . . . . . . . . . 1979 Chevrolet C70 single-unit truck Mass (kg) Curb . . . . . . . . . 5661

Test Inertial . . . . 8000 Dummy . . . . . . . No dummy Gross Static . . . . 8000

0.537 1.024 s

I ~: ifi~~~:~-~~ I 1-Bi

r ~m ~ '"'")~ ! ==I . I \ ~-]~~~~-~~·

Impact Conditions Speed (km/h) ............ 79.6 Angle (deg) . . . . . . . . . . . . . . 14.9

Exit Conditions Speed (km/h) ............ N/A Angle (deg) . . . . . . . . . . . . . . Approx. 5

Occupant Risk Values Impact Velocity (m/s)

x-direction . . . . . . . . . . . . . 2.0 y-direction . . . . . . . . . . . . . 2.6

THIV (km/h) . . . . . . . . . . . . . 10.2 Ridedown Accelerations (g's)

x-direction . . . . . . . . . . . . . -1 .9 y-direction ............. -9.6

PHD (g's) ............... 10.6 ASI ................... 0.5 Max. 0.050-s Average (g's)

x-direction . . . . . . . . . . . . . -1.5 y-direction ............. -4.5 z-direction . . . . . . . . . . . . . -2. 1

Test Article Deflections (m) Dynamic . . . . . . . . . . . . . . nil Permanent . . . . . . . . . . . . 0.01

Vehicle Damage Exterior

VDS ............... N/A CDC ............... N/A

Maximum Exterior Vehicle Crush (mm) . . . . 114

Interior OCDI . . . . . . . . . . . . . . FSOOOOOOO

Max. Occ. Compart. Deformation (mm) . . . . . 0

Post-Impact Behavior (during 1.0 s after impact) Max. Yaw Angle (deg) . . . . -13 Max. Pitch Angle (deg) . . . . 4 Max. Roll Angle (deg) . . . . 5

Figure 12. Summary of results for test 404251-3, NCHRP Report 350 test 4-12.

Page 30: NCHRP Report 350 Test 4-12 of the Massachusetts S3-TL4 ...The Massachusetts S3-TLA Steel Bridge Railing system is a beam and post system consisting of three tubular steel rail elements

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Time after impact (s)

Figure 13. Vehicle angular displacements for test 404251-3.

Pitch

Axes are vehicle-fixed . Sequence for deter­mining orientation is:

1. Yaw 2. Pitch 3. Roll

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Page 31: NCHRP Report 350 Test 4-12 of the Massachusetts S3-TL4 ...The Massachusetts S3-TLA Steel Bridge Railing system is a beam and post system consisting of three tubular steel rail elements

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Test Article: Massachusetts S3-TL4 Steel Bridge Rail on curb/sidewalk

Test Vehicle: 1988 Chevrolet C70 single-unit truck Test Inertial Weight: 8000 kg Gross Static Weight: 8000 kg Impact Speed: 49.5 krnlh Impact Angle: 14.9 degrees at CIP

0.7 0.8 0.9

Figure 14. Vehicle longitudinal accelerometer trace for test 404251-3 (accelerometer located at center of gravity).

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Page 32: NCHRP Report 350 Test 4-12 of the Massachusetts S3-TL4 ...The Massachusetts S3-TLA Steel Bridge Railing system is a beam and post system consisting of three tubular steel rail elements

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-·Test Article: Massachusetts S3-TL4 Steel Bridge Rail on curb/sidewalk

_, Test Vehicle: 1988 Chevrolet C70 single-unit truck Test Inertial Weight: 8000 kg Gross Static Weight: 8000 kg Impact Speed: 49.5 kmlh

-· Impact Angle: 14.9 degrees at CIP

0.7 0.8 0.9

Figure 15. Vehicle lateral accelerometer traces for test 404251-3 (accelerometer located at center of gravity).

1.0

Page 33: NCHRP Report 350 Test 4-12 of the Massachusetts S3-TL4 ...The Massachusetts S3-TLA Steel Bridge Railing system is a beam and post system consisting of three tubular steel rail elements

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Test Article: Massachusetts S3-TL4 Steel Bridge Rail on curb/sidewalk

Test Vehicle: 1988 Chevrolet C70 single-unit truck Test Inertial Weight: 8000 kg Gross Static Weight: 8000 kg Impact Speed: 49.5 km/h Impact Angle: 14.9 degrees at CIP

0.7 0.8 0.9

Figure 16. Vehicle vertical accelerometer trace for test 404251-3 (accelerometer located at center of gravity).

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Page 34: NCHRP Report 350 Test 4-12 of the Massachusetts S3-TL4 ...The Massachusetts S3-TLA Steel Bridge Railing system is a beam and post system consisting of three tubular steel rail elements

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Time after impact (s)

Test Article: Massachusetts S3-TL4 Steel Bridge Rail on curb/sidewalk

Test Vehicle: 1988 Chevrolet C70 single-unit truck Test Inertial Weight: 8000 kg Gross Static Weight: 8000 kg Impact Speed: 49.5 km/h Impact Angle: 14.9 degrees at CIP

0.7 0.8 0.9

Figure 17. Vehicle longitudinal accelerometer trace for test 404251-3 (accelerometer located in front section of cab of vehicle).

1.0

Page 35: NCHRP Report 350 Test 4-12 of the Massachusetts S3-TL4 ...The Massachusetts S3-TLA Steel Bridge Railing system is a beam and post system consisting of three tubular steel rail elements

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Test Article: Massachusetts S3-TL4 Steel Bridge Rail on curb/sidewalk

_, Test Vehicle: 1988 Chevrolet C70 single-unit truck Test Inertial Weight: 8000 kg Gross Static Weight: 8000 kg Impact Speed: 49.5 km/h Impact Angle: 14.9 degrees at CIP

0.7 0.8 0.9

Figure 18. Vehicle lateral accelerometer traces for test 404251-3 (accelerometer located in front section of cab of vehicle).

1.0

Page 36: NCHRP Report 350 Test 4-12 of the Massachusetts S3-TL4 ...The Massachusetts S3-TLA Steel Bridge Railing system is a beam and post system consisting of three tubular steel rail elements

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Test Article: Massachusetts S3-TL4 Steel Bridge Rail on curb/sidewalk

Test Vehicle: 1988 Chevrolet C70 single-unit truck Test Inertial Weight: 8000 kg Gross Static Weight: 8000 kg Impact Speed: 49.5 km/h Impact Angle: 14.9 degrees at CIP

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Time after impact (s)

Figure 19. Vehicle longitudinal accelerometer trace for test 404251-3 (accelerometer located over rear axle).

0.8 0.9 1.0

Page 37: NCHRP Report 350 Test 4-12 of the Massachusetts S3-TL4 ...The Massachusetts S3-TLA Steel Bridge Railing system is a beam and post system consisting of three tubular steel rail elements

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16 -14 --r----c::::::==r:~-Test Article: Massachusetts S3-TL4 Steel Bridge Rail on curb/sidewalk

_, Test Vehicle: 1988 Chevrolet C70 single-unit truck

12

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Test Inertial Weight: 8000 kg -· Gross Static Weight: 8000 kg _, Impact Speed: 49.5 km/h

Impact Angle: 14.9 degrees at CIP

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Time after impact (s)

Figure 20. Vehicle lateral accelerometer traces for test 404251-3 (accelerometer located over rear axle).

0.8 0.9 1.0

Page 38: NCHRP Report 350 Test 4-12 of the Massachusetts S3-TL4 ...The Massachusetts S3-TLA Steel Bridge Railing system is a beam and post system consisting of three tubular steel rail elements

IV. SUMMARY OF FINDINGS AND CONCLUSIONS

SUMMARY OF FINDINGS

The Massachusetts S3-TL4 Steel Bridge Railing contained and redirected the vehicle. The vehicle did not penetrate, underride, or override the bridge railing. No detached elements, fragments, or other debris were present to penetrate nor to show potential for penetrating the occupant compartment, nor to present undue hazard to others in the area. No deformation or intrusion of the occupant compartment occurred. The vehicle remained upright during and after the collision period. No intrusion into adjacent traffic lanes occurred. Exit angle at loss of contact was not attainable but was estimated to be less than 5 degrees.

CONCLUSIONS

The Massachusetts S3-TL4 Steel Bridge Railing mounted on curb and sidewalk met all criteria specified for NCHRP Report 350 test designation 4-12.

31

Page 39: NCHRP Report 350 Test 4-12 of the Massachusetts S3-TL4 ...The Massachusetts S3-TLA Steel Bridge Railing system is a beam and post system consisting of three tubular steel rail elements

w N

I

Table 1. Performance evaluation summary for test 404251-3, NCHRP Report 350 test 4-12.

TestA T T I T 40425 ~ .

NCHRP Report 350 Evaluation Criteria I Test Results

Structural Adequacy

A. Test article should contain and redirect the vehicle; the The Massachusetts S3-TL4 Steel Bridge Railing vehicle should not penetrate, underride, or override the contained and redirected the vehicle. The vehicle did installation although controlled lateral deflection of the test not penetrate, underride, or override the bridge railing. article is acceptable.

Occupant Risk

D. Detached elements, fragments or other debris from the test No detached elements, fragments, or other debris were article should not penetrate or show potential for present to penetrate nor to show potential for penetrating the occupant compartment, or present an undue penetrating the occupant compartment, nor to present hazard to other traffic, pedestrians, or personnel in a work undue hazard to others in the area. No deformation or zone. Deformations of, or intrusions into, the occupant intrusion of the occupant compartment occurred. compartment that could cause serious injuries should not be permitted.

G. It is preferable, although not essential, that the vehicle The vehicle remained upright during and after the remain upright during and after the collision. collision period.

Vehicle Trajectory

K. After collision, it is preferable that the vehicle's trajectory No intrusion into adjacent traffic lanes occurred. not intrude into adjacent traffic lanes.

M. The exit angle frolll the test article preferably should be less Exit angle at loss of contact was not attainable but was than 60 percent of test impact angle, measured at time of estimated to be less than 5 degrees. vehicle loss of con~act with test device.

* Criterion preferable, not required.

I Assessment I

Pass

Pass

Pass*

Pass*

Pass*

Page 40: NCHRP Report 350 Test 4-12 of the Massachusetts S3-TL4 ...The Massachusetts S3-TLA Steel Bridge Railing system is a beam and post system consisting of three tubular steel rail elements

REFERENCES

1. J.D. Michie, "Recommended Procedures for the Safety Performance Evaluation of Highway Appurtenances," NCHRP Report 230, Transportation Research Board, Washington, D.C., 1980.

2. H. E. Ross, Jr., D. L. Sicking, R. A. Zimmer, and J.D. Michie, "Recommended Procedures for the Safety Performance Evaluation of Highway Features," NCHRP Report 350, Transportation Research Board, Washington, D.C., 1993.

33