NCHRP REPORT 350 TEST 4-12 OF THE MASSACHUSETTS S3-TL4 STEEL BRIDGE RAILING MOUNTED ON CURB AND SIDEWALK

Transcription

1 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 Contract No. DTFH61-97-C Sponsored by U.S. Department of Transportation Federal Highway Administration July 1998 TEXAS TRANSPORTATION INSTITUTE THE TEXAS A & M UNIVERSITY SYSTEM COLLEGE STATION, TEXAS

2 I. ReportNo. 2. Government Accession No. 3. Recipient's Catalog No. FHW A-RD Title and Subtitle 5. Report Date NCHRP REPORT 350 TEST 4-12 OF THE July 1998 MASSACHUSETTS S3-TL4 STEEL BRIDGE RAILING WITH CURB AND SIDEWALK TECHNICAL REPORT DOCUMENTATION PAGE 6. Performing Organization Code 7. Author(s) 8. Performing Organization Report No. C. Eugene Buth and Wanda L. Menges Performing Organization Name and Address 10. Work Unit No. Texas Transportation Institute The Texas A&M University System College Station, Texas NCPNo. 11. Contract or Grant No. DTFH C Sponsoring Agency Name and Address 13. Type of Report and Period Covered Federal Highway Administration Test Report U.S. Department of Transportation July July Seventh Street, S.W. 14. Sponsoring Agency Code Washington, D.C 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 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 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 Security Classif. (of this report) 20. Security Classif. (of this page) 21. No. of Pages 22. Price Unclassified Unclassified 47 FormDOTF (8-69)

3 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 inches in ft feet meters m m meters 3.28 feet ft yd yards meters m m meters 1.09 yards yd mi miles 1.61 kilometers km km kilometers miles mi AREA AREA in 2 square inches square millimeters mm' mm' square millimeters square inches in 2 ft 2 square feet square meters m' m' square meters square feet ft 2 yd' square yards square meters m' m' square meters square yards yd' ac acres hectares ha ha hectares 2.47 acres ac mi 2 square miles 2.59 square kilometers km' km' square kilometers square miles mi 2 VOLUME VOLUME... Ill... fl oz fluid ounces milliliters ml ml milliliters fluid ounces fl oz gal gallons liters L L liters gallons gal ft' cubic feet cubic meters ms ms cubic meters cubic feet ft 3 yd3 cubic yards cubic meters ms ms cubic meters cubic yards yd3 NOTE: Volumes greater than I shall be shown in m 3 MASS MASS oz ounces grams g g grams ounces oz lb pounds kilograms kg kg kilograms pounds lb T short tons megagrams Mg Mg megagrams short tons T lb) lor "metric ton") lor "t") lor "t") (or "metric ton") 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 lux lx lx lux foot-candles fc fl foot-lamberts candela/m 2 cd/m 2 cd/m 2 candela/m foot-lamberts fl FORCE and PRESSURE or STRESS FORCE and PRESSURE or STRESS lbf poundforce 4.45 newtons N N newtons poundforce lbf lbf/in' poundforce per 6.89 kilopascals kpa kpa kilopascals 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.

4 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 (NCHRP Report 350 test no. 4-12)... 9 Test Description... 9 Damage to Test Installation Vehicle Damage Occupant Risk Values IV. SUMMARY OF FINDINGS AND CONCLUSIONS SUMMARY OF FINDINGS CONCLUSIONS REFERENCES iii

5 LIST OF FIGURES Figure No. Page 1 Details of the Massachusetts S3-TL4 Steel Bridge Railing mounted on curb and sidewalk Massachusetts S3-TL4 Steel Bridge Railing mounted on curb and sidewalk before test Vehicle/installation geometries for test Vehicle before test Vehicle properties for test Sequential photographs for test (overhead and frontal views) Sequential photographs for test (close-up frontal and rear views) Afterimpacttrajectoryfortest Installation after test Vehicle after test Interior of vehicle for test Summary of results for test , NCHRP Report 350 test Vehicle angular displacements for test Vehicle longitudinal accelerometer trace for test (accelerometer located at center of gravity) Vehicle lateral accelerometer traces for test (accelerometerlocated at center of gravity) Vehicle vertical accelerometer trace for test (accelerometerlocated at center of gravity) Vehicle longitudinal accelerometer trace for test (accelerometer located in front section of cab of vehicle) Vehicle lateral accelerometer traces for test (accelerometer located in front section of cab of vehicle) Vehicle longitudinal accelerometer trace for test (accelerometer located over rear axle) Vehicle lateral accelerometer traces for test (accelerometer located over rear axle) iv

6 LIST OF TABLES Table No. Page 1 Performance evaluation summary for test , NCHRP Report 350 test v

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8 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

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10 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 3

11 --{'.-" -=----~ ~-~~...-,..-~... =========== ~= =::.::.::::;.. ~.. ~.. :;:.=:;:;:... ~.. :;:;:. =...,,,.,,,.,..,.,.,,.,.,,.,,., "'"-"'-"' ~"' ' ''''~"' ~ co ~o '"-'''" '' ' '..,._ c:c ~ cc ~- ~I ~~~~~~~1550--~~~~~~- (Sidewalk Width) ~~-23,000~~~~~~~~~~~~~~~-j ITl ===-l=.. =cc==j UNREINFORCED CONCRETE SI.AB ~ ~ ~L] EXISTING FOUNDATION ~ v 38 x thk. x 985 long PICKETS 25 MIN. 1 (TYP.) L76x51x6.4 DETAIL 11 j(typ.)], DETAIL B EFFECTIVE JOIN1 WIDTH + 15 AT BRIDGE EXPANSION JOINT I O'C AT TYPICAL RAIL SPLICES) 50 CL. 4' 700 (SPLICE TUBE) W150x37 (NP.) NOTES: 1. FOR DETAILS NOT SHOWN, SEE MASS. STANDARD DRAWING DATED JUNE 27, 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 POST (f. The Texas A&M University System BRIDGI!'AILING ELEVATION (FIELD SIDE) '""'''"" I I TEXAS TRANSPORTATION INSTITUTE Dolo '' COLLEGE STATION, TEXAS Scele Figure 1. Details of the Massachusetts S3-TL4 Steel Bridge Railing mounted on curb and sidewalk.

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

13 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 ) corresponds to NCHRP Report 350 test designation 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. 6

14 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 7

15 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 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. 8

16 III. CRASH TEST RESULTS TEST (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, 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 s the wheels turned to the right (toward the bridge rail) and then straightened. By s the right front wheel reached the top of the sidewalk. At 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 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 sand the right front tire contacted the lower element at s. Redirection of the vehicle occurred at s. The lower front right corner of the box reached the top of the top rail element at s. At 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 m down and 5.3 m behind the bridge rail. Sequential photographs of the collision period can be found in figures 6 and 7. 9

17 Figure 3. Vehicle/installation geometries for test

18 Figure 4. Vehicle before test

19 -~ _9~LiL~--~-~--... C.b.e.v.r.o.Le.-1...l......!... 22~ B.D.O... : ~ : :Z.O_~~ _: P.. =~ / '-' c:::-:,- -,,.._,_,.._; \... ~---!.,! = :;, Figure 5. Vehicle properties for test

20 0.000 s s s s Figure 6. Sequential photographs for test (overhead and frontal views). 13

21 0.537 s s s s Figure 6. Sequential photographs for test (overhead and frontal views) (continued). 14

22 0.000 s s s s Figure 7. Sequential photographs for test (close-up frontal and rear views). 15

23 0.537 s s s s Figure 7. Sequential photographs for test (close-up frontal and rear views) (continued). 16

24 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 s, the highest s occupant ridedown acceleration was -1.9 g's from to s, and the maximum s average acceleration -1.5 g's between and s. In the lateral direction, the occupant impact velocity was 2.6 m/s at s, the highest s occupant ridedown acceleration was -9.7 g's from to s, and the maximum s average was -4.4 g's between and 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

25 Figure 8. After impact trajectory for test

26 Figure 9. Installation after test

27 Figure 10. Vehicle after test

28 Before test After test Figure 11. Interior of vehicle for test

29 ~.m:~~~?j.:?x::t::;\%i:;;;;:)~~-::i:::~).~. "ii~;&""~:.:.'~fi-s,~~,,.v..,,.,... :;~}~),.,~.,.,.,.,;,; I ==;::t-t~w.e~~.. <t~~~\~ ;.:~}~~: ;,:;_::~:tj~~~; ~~;,.~«<~..;J~.: s s 03.6 rn I r ~: ifi~~~:~-~~ I 1-Bi ~m ~ '"'")~! ==I. I \ ~-]~~~~-~~ N N General Information Test Agency Texas Transportation Institute Test No Date /19/98 Test Article Type Bridge Rail Name Mass. S3-TL4 on curb/sidewalk Installation Length (m) 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 S Model Chevrolet C70 single-unit truck Mass (kg) Curb Test Inertial Dummy No dummy Gross Static Impact Conditions Speed (km/h) Angle (deg) Exit Conditions Speed (km/h)... N/A Angle (deg) Approx. 5 Occupant Risk Values Impact Velocity (m/s) x-direction y-direction THIV (km/h) Ridedown Accelerations (g's) x-direction y-direction PHD (g's) ASI Max s Average (g's) x-direction y-direction z-direction Test Article Deflections (m) Dynamic nil Permanent Vehicle Damage Exterior VDS... N/A CDC... N/A Maximum Exterior Vehicle Crush (mm) Interior OCDI FSOOOOOOO Max. Occ. Compart. Deformation (mm) Post-Impact Behavior (during 1.0 s after impact) Max. Yaw Angle (deg) Max. Pitch Angle (deg) Max. Roll Angle (deg) Figure 12. Summary of results for test , NCHRP Report 350 test 4-12.

30 Crash Test Vehicle Mounted Rate Transducers ~ N (.;,) -en Q) "C -.. r::: Q) E Q) 0 co c. II) ~.--, '--. /. \ ;r':\ -J. '. ' "\ I, - -c-' ". 'A:./"-. /, ~ -,.. ' I \"'!.'(.., r,. /l>r./--'~ '. Y ~,..... "/"- ; 1. \. _...-' 2 o-<' \~ I 4 \/ '-,_ ' --"-". --,.~, ':... " ~ ~ A.....,., I ~".!/ ' ~ 1 ' \, - /..,,/ \ \ I I I \ \ I ' ' I ' \ ' /. ' \ \./ \ '~/ - \ \ -\. \ \ \ \' \ \ -'\ ' ' ' \ ' ' \,- \ \ ' \ -,-.\\ \., Pitch Axes are vehicle-fixed. Sequence for determining orientation is: 1. Yaw 2. Pitch 3. Roll Roll I <'!< --~.J?f~O\..\.. -~ ~ '-:?-;;...:.'!:.1?11( "7i)l~<Q!h" -, ---" " CO. N.rZ I... rai ' ' ' -\,- \ \ ' ' ' :..- ''\ ', ' / _,_ ' /' -_./-' ' '..... Yaw -14-L ~ Time after impact (s) Figure 13. Vehicle angular displacements for test

31 [ 60 Hz Filter I Crash Test Accelerometer at center of gravity N..p. en ~ t J\ ll c: 0 -:;:; IU Ill Gi CJ CJ IU ov~vvvvv -4-6 iii c: 'C -8 :I - c;, c: I /\1. ~ -~-. AflA~~-- f.."l"ft-.-- "j_j - "J\J~~ AA A A ~r rvv VV"[v-~v ~-~ ~v-vv ~vv 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 ' Time after impact (s) Figure 14. Vehicle longitudinal accelerometer trace for test (accelerometer located at center of gravity).

32 Ui' 0 :9 c::.!2 1ii Gl a; (.) N (.) -6 VI 111 ca Gl ' -10 I Elcl Hz Filter I Crash Test Accelerometer at center of gravity 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 Time after impact (s) Figure 15. Vehicle lateral accelerometer traces for test (accelerometer located at center of gravity).

33 10 [6oH~I -~~~- Crash Test Accelerometer at center of gravity N 0'1 'iii' s 0 c -2 0 ; ftl... -4!! Cll (,) (,) ftl iii (,) -6-8 t: Cll > 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 Time after impact (s) Figure 16. Vehicle vertical accelerometer trace for test (accelerometer located at center of gravity).

34 20 I 60UH-; Filter I Crash Test Accelerometer in front section of cab of vehicle Iii' 8 ~ c 6 0 ; 4.. Ill Gl 2 G.i u u 0 Ill tv 'iii ) c :c -4 :2 Cl -6 c 0.J 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 Time after impact (s) Figure 17. Vehicle longitudinal accelerometer trace for test (accelerometer located in front section of cab of vehicle).

35 20 r 66 H~Fi~~r I Crash Test Accelerometer in front section of cab of vehicle U) 6 :9 c 4 0 :;:; I'll... 2 Cll Gi 0 N u I'll iii Cll I'll -6..J -8 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 Time after impact (s) Figure 18. Vehicle lateral accelerometer traces for test (accelerometer located in front section of cab of vehicle).

36 'iii' 8 :9 c 6 0 ':;:::; 4 Ill... G) 2 Gi u Ill 0 N \0 iii c -2 =c -4 :I - a, -6 c 0.J I 60 H~ FUte~ I Crash Test Accelerometer over rear axle.~ J.~. ~ 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,_,,6,1,. = ---"-m. I "' "'""'-' ~ Time after impact (s) Figure 19. Vehicle longitudinal accelerometer trace for test (accelerometer located over rear axle).

37 w 0 Iii' s c: 0... ~ Q) 8 g iii...! Ill...I ~~ I I ~.. ~l~~---~--_!.~~~~~~; 1-6o H~yrner] Crash Test Accelerometer over rear axle r----c::::::==r:~- 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 v '-j~ _L, Time after impact (s) Figure 20. Vehicle lateral accelerometer traces for test (accelerometer located over rear axle).

38 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

39 w N I Table 1. Performance evaluation summary for test , NCHRP Report 350 test TestA. T T I T ~ 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*

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