II ;:;:i;:;~::~stitute I~~;;;:~ II

Transcription

1 TECHNCAL REPORT DOCUMENTATON PAGE llrfh_1._r~-~~-~-~rd -_96_ ~2_.~ ~_A_~_i - N_ r~-3-.~- _p~_,_~_~_n_ ~~~ 11 Ti~oaodSubti~o ~U_.:...~_; 1 _ ill NCHRP REPORT 350 COMPLANCE TESTS OF THE ~- Performi,.o~ouCodo V-LOC SGN SUPPORT SYSTEM f i ~~;;lp. Bligh, Wanda L. Menges, and Dean C. Alberson ~; :;;;--;~5:;N~--1F ;:;:i;:;~::~stitute ~~;;;:~ The Texas A&M University System 111. coatnotorgromno. College Station, Texas Spouoriac At«J1:Y Name ud Addroa 13. Typo afroport ODd Period Covorod Foresight Products, nc East 49th Drive Commerce City, CO i--1 Final Report March through April Spoaoori,. N!...:Y Codo Name of contacting representative: Tom Bird Senior Engineer 16. Abltract Foresight Products, nc. contracted with the Texas Transportation nstitute (TTl) to evaluate the safety performance of their V-Loc sign support socket when tested in accordance with the recommended guidelines contained in National Cooperative Highway Research Program (NCHRP) Report 350. Previous approval of this socket and wedge system was based on crash tests conducted a kg vehicle. n order to satisfy NCHRP Report 350 and, thereby, retain its approved status, it was required that the V-Loc sign support system be successfully tested with an 820-kg vehicle. This report details the construction, performance, and evaluation of the full-scale crash tests performed on the V-Loc sign support system. The sign support types used in the testing program included a 5.95 kg/m U-channelpost and a 60.3 mm O.D. x 2.4 mm wall steel tube sign support. n all tests, the V-Loc sign support system performed satisfactorily by yielding to the vehicle and then fracturing or pulling out of the socket. The occupant risk indices were well below the recommended values contained in NCHRP Report 350. The V-Loc sign support socket was found to meet all relevant evaluation criteria for NCHRP Report 350 test designations 3-60 and 3-61 for both the U-channel and thin-wall round tube sign supports. Moreover, the successful results with these supports indicates that the V-Loc socket should also perform satisfactorily with other sign support types provided the yield moment of the support does not exceed that of those tested under this study. 17. KoyWordo Sign supports, U-channel, crash testing, roadside safety 18. Distribution Statem.eat No restrictions. This document, if published, is available to the public through National Teclmical nformation Services, 5285 Port Royal Road, Springfield, Vrginia ~ll=~=~=cl=~=~=m=.ed=~=~= -==~===============!'=~=~n=~=las= =~= ~=~=af=~ =~= =)================'l=2=1.=~=.af=~=-=====9=7========='1 npri~ Form DOT F (8-69)

2 Symbol When You Know Multiply By To Find.Symbol Symbol When You Know Multiply By To Find Symbol LENGTH LEN~TH 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 in 2 square inches square millimeters mm 2 mm2 square millimeters square inches in 2 ft2 square feet square meters mz mz square meters square feet ft2 yr:j2 square yards square meters mz mz square meters square yards yr:j2 ac acres hectares ha ha hectares 2.47 acres ac mi2 square miles 2.59 square kilometers km 2 km2 square kilometers square miles mi 2 VOLUME VOLUME 1-' 1-' ll ft oz fluidounces milliliters ml ml milliliters fluidounces fl oz gal gallons liters L L liters gallons gal ft' cubic feet cubic meters ma ma cubic meters cubic feet ft' ycfl cubic yards cubic meters ma ma cubic meters cubic yards ycfl NOTE: Volumes greater than 1000 shall be shown in m 3 MASS.( oz ounces grams.f.- g g grams ounces oz lb pounds kilograms kg kg kilograms pounds lb T short tons (2000 lb) megagrams Mg Mg megagrams short tons (2000 lb) T (ot "metric ton") (or "t") (or "t") (or "metric ton") TEMPERATURE (exact) TEMPERATURE (exact) OF Fahrenheit 5(F-32)19 Celcius oc oc Celcius Fahrenheit OF temperature or (F-32)11.8 temperature temperature temperature LLUMNATON AREA MASS LLUMNATON fc foot-<:andles lux lx lx lux foot-candles fc ft foot-lambert& 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 lbflin 2 poundforce per 6.89 kilopascals kpa kpa kilo pascals poundforce per lbflin 2 square inch square inch Sl a the symbol for the lntematlonal System of Units. Appropriate (Revised September 1993) rounding should be made to comply

3 TABLE OF CONTENTS. NTRODUCTON T. STUDY APPROACH... 3 V-LOC SOCKET WTH U-CHANNEL SGN SUPPORT... 4 V-LOC SOCKET WTH THN WALL ROUND TUBE SGN SUPPORT... 7 CRASH TEST CONDTONS NCHRP Report 350 Test Designation NCHRP Report 350 Evaluation Criteria CRASH TEST AND DATA ANALYSS PROCEDURES Electronic nstrumentation and Data Processing Anthropomorphic Dummy nstrumentation Photographic nstrumentation and Data Processing Test Vehicle Test Vehicle Propulsion and Guidance ill. CRASH TEST RESULTS V-LOC SOCKET WTH U-CHANNEL SGN SUPPORT Low-Speed Test (Test ) High-Speed Test (Test ) V-LOC SOCKET WTH THN-WALL ROUND TUBE SGN SUPPORT Low-Speed Test (Test ) High-Speed Test (Test ) V. FNDNGS AND CONCLUSONS SUMMARY OF FNDNGS CONCLUSONS APPENDX A. VEHCLE PROPERTES APPENDX B. SEQUENTAL PHOTOGRAPHS APPENDX C. VEHCLE ANGULAR DSPLACEMENTS APPENDX D. VEHCLE ACCELEROMETER TRACES REFERENCES iii

4 LST OF FGURES Figure No. Page 1 Details of the V-Loc sign support system with U-channel post for tests and nstallation instructions for V-Loc sign support system Details of the V-Loc sign support system U-channel adaptor Details of the V-Loc sign support system wedge Details of the V-Loc sign support system with round tube post for tests and V-Loc sign support system with U-channel post before test Vehicle/installation geometries for test Vehicle before test After impact trajectory for test nstallation after test Vehicle after test Summary of results for test V-Loc sign support system with U-channel post before test Vehicle/installation geometries for test Vehicle before test nstallation after test Vehicle after test Summary of results for test V-Loc sign support system with round tube post before test Vehicle/installation geometries for test Vehicle before test After impact trajectory for test nstallation after test Vehicle after test Summary of results for test V-Loc sign support system before test Vehicle/installation geometries for test Vehicle before test After impact trajectory for test nstallation after test Vehicle after test Summary of results for test Vehicle properties for tests through Sequential photographs for test (perpendicular and frontal views) Sequential photographs for test (perpendicular and frontal views) Sequential photographs for test (perpendicular and frontal views) iv

5 LST OF FGURES (continued) Figure No. Page 37 Sequential photographs for test (perpendicular and frontal views) Vehicle angular displacements for test Vehicle angular displacements for test Vehicle angular displacements for test Vehicle angular displacements for test Vehicle longitudinal accelerometer trace for test Vehicle lateral accelerometer trace for test Vehicle vertical accelerometer trace for test Vehicle longitudinal accelerometer trace for test Vehicle lateral accelerometer trace for test Vehicle vertical accelerometer trace for test Vehicle longitudinal accelerometer trace for test Vehicle lateral accelerometer trace for test Vehicle vertical accelerometer trace for test Vehicle longitudinal accelerometer trace for test Vehicle lateral accelerometer trace for test Vehicle vertical accelerometer trace for test LST OF TABLES Table No. Page 1 Properties of common small sign supports Performance evaluation summary for low-speed test on V-Loc sign support system with U-channel post, NCHRP Report test Performance evaluation summary for high-speed test on V-Loc sign support system with U-channel post, NCHRP Report test Performance evaluation summary for low-speed test on V-Loc sign support system with round tube post, NCHRP Report test Performance evaluation summary for high-speed test on V-Loc sign support system with round tube post, NCHRP Report test v

6

7 . NTRODUCTON Foresight Products, nc. contracted with the Texas Transportation nstitute (TTl) to evaluate the safety performance of their V-Loc sign support socket. The objective of the test program is to determine whether the V-Loc sign support socket meets the performance criteria outlined in National Cooperative Highway Research Program (NCHRP) Report 35d 1 > and is acceptable for continued application throughout the country. Previous approval of this socket and wedge system was based on crash tests conducted at TTl with a 1020-kg vehicle. (2, 3 ) n order to satisfy NCHRP Report 350 and, thereby, retain its approved status, it was required that the V-Loc sign support system be successfully tested with an 820-kg vehicle. This report details the construction, performance, and evaluation of the full-scale crash tests performed on the V-Loc sign support system. The crash tests were performed in accordance with NCHRP Report 350 guidelines. The tests were evaluated in accordance with NCHRP Report 350 and the 1994 American Association of State Highway Transportation Officials (AASHTO) Standard Specifications for Structural Supports for Highway Signs, Luminaires, and Traffic Signals. < 4 > 1

8

9 ll. STUDY APPROACH The V-Loc socket system is designed for use with several different sign support types, including perforated square tubing, thin-wall round tubing, and U-channel. For each sign support (i.e., for a given post shape and size), there are typically three different socket designs available which differ only in the length of the leg angle. The length of the leg angle varies according to the type of foundation material being used. When embedded in a concrete footing, the length of the leg angle is 203 mm. For direct embedment applications, the length is increased to 762 mm. Since the impact performance of the driven V-Loc system depends on dynamic soilstructure interaction, it would be desirable to test the socket in soil conditions that replicate typical in-service conditions. However, since the V-Loc system has nationwide application, soil conditions will vary considerably. n the absence of a specific soil, NCHRP Report 350 recommends that all features whose impact performance is sensitive to soil-structure interaction be tested with a "standard" soil. Therefore, all testing of the V-Loc socket performed under this study and reported herein was conducted in standard soil as defmed in Section of NCHRP Report 350. Since a variety of support posts are commonly used in conjunction with the V-Loc socket, the critical support post configurations were selected for testing and evaluation in order to minimize the required test matrix. The implication is that if the critical sign support systems pass the required compliance tests ofnchrp Report 350, the V-Loc anchor design would be judged to be crashworthy for other less critical systems as well. n other words, if the critical systems pass the applicable test requirements, it is reasonable to assume that less critical supports would also perform satisfactorily. Based on the results of a field survey performed by Foresight Products, nc., the three support posts most commonly used with the V-Loc Socket are: (a) 60.3-mm diameter thinwall steel tube, (b) 50.8-mm square perforated steel tube, and (c) 5.95 kg/m U-channel. The intent of the testing program initiated by Foresight Products, nc. was to satisfy NCHRP Report 350 requirements for these supports when used with the V-Loc socket. For proper performance, the V-Loc design relies on yielding of the sign support and the subsequent fracture or release of the sign support from the anchor socket. Based on an analysis of material and section properties (see table 1), two different sign support systems were selected for testing: a 60.3-mm diam. x 2.4-mm wall steel tube, and a 5.95 kg/m U-channel. The 60.3-mm diam. x 2.4-mm wall steel tube was selected because it has the highest yield moment of the commonly used support types. Although the 5.95 kg/m U-channel has a higher yield moment than the thin wall tube, it is used in conjunction with an adaptor post which has a smaller yield moment than both the perforated square tubing and the thin-wall round tubing. However, given that the performance of the U-channel post is dependent on the behavior of the special weakened adaptor, it was also selected for testing under this study. 3

10 Table 1. Properties of common small sign supports. Support Type Material Size Perforated Square ASTMA mm x 50.8 mm x 2.7 mm Tubing (2" X 2" X 0.105") Thin-Wall Round ASTMA mm O.D. x 2.4 mm wall Tubing (2.375" O.D. x 0.095" wall) U-Chaonel U-Channel Adaptor ASTMA-449 ASTMA-500 GradeB 5.95 kg/m (4 lb/ft) 48.3 mm O.D. x 3 mm wall (1.90" O.D. x 0.120" wall) "AASHTO "A Guide to Small Sign Support Hardware" b Southwest Pipe, nc. o WJ.weakened section Section Modulus mm3 (in 3 ) 6,096 ~ (0.372)" 6,112 (0.373)b 9,767 (0.596)" 4,605 (0.281) Yield Stress MPa (ksi) Yield Moment N-m _Ob-in) ,386 (33) (12,276) ,316 (55)b (20,515) ~ 4,037 ) (35,760) [][ 1,332 ) (11,802)" Details of the V-Loc sign support socket for thin wall round steel tubing and U-channel, as constructed and tested under this study, are given below. V-LOC SOCKET WTH U-CHANNEL SGN SUPPORT The V-Loc socket for U-channel sign supports is constructed from 63.5 mm x 63.5 mm x 6 mm angle steel and 2.7-mm. thick steel plate. The angle, which is 762 mm long, serves as the leg of the ground anchor. The 2.7-mm. steel plate is bent into a "V'' shape and welded flush with the top of the angle form a socket. A 19-mm. diameter x 178-mm. long hot rolled round bar extends diagonally from the bottom comer of the "V'' shaped plate to the angle. n addition to serving as a brace for the socket system, the rod also helps prevent soil from accumulating in the socket during driving. The steel plate is fabricated from ASTM A-569 steel, and the angle and rod are fabricated from A-36 steel. Additional details and dimensions of the V-Loc socket for U-channel supports is shown in figure 1. nstallation procedures for driving and erecting the V-Loc sign support system, as supplied by the manufacturer and followed during the testing program, are illustrated in figure 2. The V-Loc socket is driven into the ground using a special drive head tool attached to a jack hammer. The drive head tool is placed atop the V-Loc socket and the unit is driven into the ground until approximately one-half of the socket is embedded. After checking for plumb, the socket is driven the remainder of distance until the top of the support is at ground 4

11 Hx TOP VEW T 241±13 j_ - 61)5~-1~0 254± r ~ - <&- D D g D D 0 A ~ - ~A ' u. - 7{52±1~ FRONT VEW HOT ROLLED ROUND BAR S~.. lil!inttpo,e.fydrfoit!!iiiomt ~'Nt'.UOU9EN. 1MUROfJ'NifJif1J... F~:~:&E~iii~l:i=~l'i~~ l(ll. _U SDE VEW J4-3±13 AlL 01 MEMil<;;iNS N 11\M 6 _/ ~ 63.~ STOCK--A '( SECTON A-A A fl t..g REt..OV 0 SCAL \CORRECfED FN Dl M. a96 CHANCED PROFLE ON FNS f'er T.ll~"lo."':!>LU'\1~ NCHES... ~. t..g DR\WNG ORGNAliON.1,1'1 ~~r ve<~ by TJ chc::c:kcd b drovn by MG Figure L Details of the V-Loc sign support system with U-channel post for tests and 3. FORESGHT PRODUCTS inc ( ~O.S) ll955o V-LOC SGN SUPPORl SOCKEl FOR U-CHANNEL 1itle D'e:U: p 20[]48 1/1 A ftu111ber

12 Foresight Products nc V-Loc Sign Support System nstallation nstructions jrefer to the figure below: 1) Place Drive Head Tool (or Power Drive Head Tool), onto V-Loc Socket top. Place Socket upright, in location where sign will be placed, and according to the orientation shown to the right. Using a level or similar device, make sure Socket is plumb. 12) Cease drive when Socket is about 'h way in ground. Again check for plumb. 3) Drive Socket until top is flush, or slightly countersunk, with ground level. Remove Drive Head. Tamp soil around Socket if soil disturbance is noted. Tamp soil inside Socket to ensure a 127 mm cleaned out depth. Nll"Jt: Dlfrfft:H ~;R~ENTA.ru;N ) ( fofl U-CMANEL 51t:iill 'OST V-LDC FOR U-CH>.NN El"' LE\>EL GROUND LEVEL\ TAAP FOR 5 ' DEPTH ~ - OREC110N Df TR/>JFC 4) nstall appropriate Sign/Post combination into Socket. Place Post 114 mm to 140 mm into Socket, next to V-Loc Leg Angle. nsert Wedge between Post and Socket wall. Hammer Wedge until flush with Socket top. nstallation should be similar to below: AP?ROPR ATE A.ll"ll.CH ENT / /S~ /~GN DRECTON OF TRAFFC F"PR<JPR late A. TTACH M E:NT Figure 2. nstallation instructions for V -Loc sign support system. 6

13 level. Note that when used with the U-channel sign support, the socket is installed with the open end of the "V'' shaped plate facing away from the direction of traffic. After the driving is complete, the soil around the socket is tamped and the soil inside the socket is removed and/or tamped to provide a cleaned out depth of 127 mm. AU-channel post adapter, shown in figure 3, is used in conjunction with the U channel sign support. The adapter is fabricated from 48-mm O.D., 11-gauge zinc coated mechanical tubing. Four slotted holes are punched into the adaptor a distance of 127 mm from the bottom edge to facilitate breakage upon impact. The upper portion of the adaptor tube is slightly flattened into an elliptical shape to facilitate connection to the U-channel post. The outside dimensions on the flattened portion measure 53 mm and 41 mm along the major and minor axes, respectively. The adaptor is attached to the U-channel using two 11.1-mm diameter bolts spaced 76 mm apart. The adapter is inserted 127 mm into the socket such that the weakening holes were level with the top edge of the socket. A triangular shaped wedge, shown in figure 4, is then used to secure the adaptor inside the socket. The wedge, which is formed from 12-gauge round mechanical tubing, is driven into the socket until flush with the top. The U-channel used in the testing was provided by Chicago Heights Steel. t had a weight of 5.95 kg/m and a minimum yield point of MPa. A 0.6 m by 1.2 m aluminum sign panel was bolted to the U-channel. The distance from the ground to the bottom of the sign panel (i.e., mounting height) was 2.13 m. V-LOC SOCKET WTH THN WALL ROUND TUBE SGN SUPPORT The V-Loc socket for thin-wall round steel tube sign supports is identical in construction to that used for the U-channel described above. Relevant details and dimensions are shown in figure 5. The installation of the socket for the tests conducted with the round tube sign supports are the same as previously described. The V-Loc socket is driven into the ground using a special drive head tool attached to a jack hammer. The drive head tool is placed atop the V Loc socket and the unit is driven into the ground until approximately one-half of the socket is embedded. After checking for plumb, the socket is driven the remainder of distance until the top of the support is at ground level. However, when used with the round steel tubing, the socket is installed with the open end of the "V'' shaped plate facing toward the direction of traffic. After the driving is complete, the soil around the socket is tamped and the soil inside the socket is removed and/or tamped to provide a cleaned out depth of 127 mm. The round tube sign support is then inserted directly into the socket to a depth of 127 mm. A triangular shaped wedge is then used to secure the sign support inside the socket. The wedge, which is formed from 12-gauge round mechanical tubing, is driven into the socket until flush with the top. 7

14 t l ±13 1'9.5 THRU 4 PLC5 TH:S R61'(1Nii S lhe PAOPER1Y (F" RJRESGMT PR>DUCTS NC. ANO USf ANY MAN Ell )( lrmeu Al TO l>l[ N11:i[ST OC <OR~SCH PAOOUeTS S PAO"BillD. TillS O!:JANJN[; ~ NOl H> Q( DSlRQU llo WTJ.~OUT < SGNED NON OSD-D!SU,.,;:,.._GRfENfNT. E9l ~p 4 PLCS SECTON A-A ALL DMENSONS N t.lt.l A t.a ~ REVECN OATE HY D!MEN SJ DNS N 01111EN~C>N~ tciferonce!ll l/'u3lsl0(hco'lichtif:eo X. t:.25-d i ~;~x MG R(l-!01.1::0 SCALE ~(,2f MG DR ~W N G <JRGN\ TON H~~ X.XXX.t.OJD G<U& Pf:UN> ld[~ lijbg; ZNC 1'\..CM' OOAT M 10 A!TM A-500-B tr fq. ma-<jriol lscole: opprov9d by T.J che<kod ~Y lb drolfn bv 1110 DESCRPTON ~~FORESGHT i PRODUCTS inc {JOJ) 2Hfi-8'il:l~ U-CHANNEL POS1 ADAPTOR Tit! e a~ 91![: /1 A n~mb~r r~v Figure 3. Details of the V-Loc sign support system U-channel adaptor.

15 lh~ DRAMNr; S: TH f PR ;Pf:Rlr Qf f1jrf:s:th r PRODUCfS NC. ~'NO US~ N 1\W Y M"'NNE:A' OE:lAtMENT#rol T<> TH f NlERfi!T ~F FDRf~CHT PROOVC15 S PRDHBilEO, 'll-s DRArflNG S NOT TO B[ OSTllliUTD \ttl-lout '- SGNED NO! DSClOSURE AGREEMENT. AJXLLARY QC AEWS ~ \0 BOTTOM VEW 1<12 [r tjt TOP VEW B 142NJs MG REMOVED SCALE A 1J2j10/1ll 1995 MG ADO ED "TOLERANCES e 21 19'1J15 TB 11 ~p2-5 CHf>.NOEO DRf>.W N G NO ~~ RJ ORA.N'N G OR Cl NA lion ~REV f<n DA 1E gj~~ft~t;;sjn x:xx x.xxx ~ "i:'f?.~,~;~"liianor!mtmf4 l6n.l tt-.5gj...e 5(;1'lf 1!1,0 lr.:l FORESGHT PRODUCTS inc ~ \303} 28~-8955 V-LOC fdrt.leo f>.nd PUNCHED WEDGE All >MEN SQNG N MM...""',; &oolw; 1111e app.ro'loed b J rhrcted bj Tl J B drown b>r 0 nurn1711r Figure 4. Details of the V-Loc sign support system wedge.

16 TOP VEW 2.7 T 241±13 _L..._ 254± t?sa-1aa!r"~ = ~A 0 0 g 0 ~ u 0 '! g ~ 0 l.~ = ~A! '... 0 ~ 7oZ±1~ FRONT VEW 17B±13 HOT ROLLED ROUND BAR ~~afl~~!i.rofu~nt~.. ~~1fmMDT4 1D1HflllR:SlfS.ra=E!H"P~!lPDK811Do 1H&:ORllf1USNJTf.OEOSliiUltC111HOf A!CJED N\N DS~~tiiiE OEUNT. 356±13 t SDE VEW ALL OM[NSDNS N MN STOCK < 1 SECTON A-A N<ll RElo10VEO SCALE\CORR ECTE> fin Dl M, DR\WNG ORG1Ni\110N :::~':'_L, -r.l FORESGHT PRODUCTS fnc ( JOS) 266-8'ilE>5o moteriol!scale! ~ppr~v~d by T J... h~.;hidpyb drovn by MG Figure 5. Details of the V-Loc sign support system with round tube post for tests and 4. V-LOC SGN SUPPOR1 SQCKE1 FQR ROUND 1UBE 1itle (a~:~a, e 2oo~o 111 A nurnb!r

17 The 60.3 mm O.D. x 2.4 mm wall round tubing used in the testing was provided by Webco ndustries, nc. A material test report indicated that the tubing, which was fabricated from ASTM A-513 steel, had a yield strength of MPa, an ultimate tensile strength of MPa, and a ductility of 17 percent. A 0.9 m by 1.2 m aluminum sign panel was attached to the round tube support using two steel strap clamps. The distance from the ground to the bottom of the sign panel (i.e., mounting height) was 2.13 m. CRASH TEST CONDTONS NCHRP Report 350 Test Designation According to NCHRP Report 350, two crash tests are required for test level three (TL-3) evaluation of support structures. They are as follows: NCHRP Report 350 test designation 3-60: 820C vehicle impacting the support structure at a speed of 3 5 km/h with the vehicle bumper at an impact angle between 0 and 20 degrees. The primary purpose of this test is to evaluate the breakaway, fracture, or yielding mechanism of the support as well as occupant risk. NCHRP Report 350 test designation 3-61: 820C vehicle impacting the support structure at a speed of 100 km/h with the vehicle bumper at an impact angle between 0 and 20 degrees. The main objective of this test is to evaluate occupant risk, and vehicle and test article trajectory. Test designations 3-60 and 3-61 were performed on both the U-channel and round tube sign support systems. All of the test installations were erected in NCHRP Report 350 standard soil. NCHRP Report 350 Evaluation Criteria The crash tests performed under this study were evaluated in accordance with the criteria presented in NCHRP Report 350 and the 1994 AASHTO standards. 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 of NCHRP Report 350 were used to evaluate the crash tests reported herein: Structural Adequacy B. The test article should readily activate in a predictable manner by breaking away, fracturing, or yielding. 11

18 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. E. Detached elements, fragments or other debris from the test article, or vehicular damage should not block the driver's vision or otherwise cause the driver to lost control of the vehicle. H. Occupant impact velocities should satisfy the following: Longitudinal Occupant mpact Velocity - m/s Preferred Maximum 3 5. Occupant ridedown accelerations should satisfy the following: Vehicle Trajectory Longitudinal Occupant Ridedown Accelerations - g' s Preferred Maximum K. After collision it is preferable that the vehicle's trajectory not intrude into adjacent traffic lanes. N. Vehicle trajectory behind the test article is acceptable. n addition, the 1994 AASHTO Standard states: Satisfactory dynamic performance is indicated when the maximum change in velocity for a standard 1800 lb (816.5 kg) vehicle, or its equivalent, striking a breakaway support at speeds of 20 milh to 60 milh (32 km/h to 97 kmlh) does not exceed 16 ft/s (4.87 m/s), but preferably does not exceed 10 ft/s (3.05 m/s) or less. 12

19 CRASH TEST AND DATA ANALYSS PROCEDURES The crash test and data analysis procedures followed in this study were in accordance with guidelines presented in NCHR.P Report 350. Brief descriptions of these procedures are presented below. Electronic nstrumentation 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 gage 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 FM/FM 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. Pressure sensitive 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, were received at the data acquisition station, and demultiplexed into separate tracks of nter-range nstrumentation Group (.R..G.) tape recorders. After the test, the data were played back from the tape machines, filtered with an SAE J211 filter, and digitized using a microcomputer, for analysis and evaluation of impact performance. The digitized data were then processed using two computer programs: DGTZE and PLOT ANGLE. Brief descriptions on the functions of these two computer programs are provided as follows. The DGTZE 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 1 O-ms average ridedown acceleration. The DGTZE program also calculates a vehicle impact velocity and the change in vehicle velocity at the end of a given impulse period. n 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 for. the longitudinal, lateral, and vertical directions were plotted using a commercially available software package (QUATTRO PRO). 13

20 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 nstrumentation An Alderson Research Laboratories Hybrid, 50th percentile male anthropomorphic dummy, restrained with lap and shoulder belts, was placed in the driver's position of the 820C vehicle. The dummy was un-instrumented. Photographic nstrumentation and Data Processing Photographic coverage of each test included two high-speed cameras: one placed behind the installation at an angle, and one placed to have a field of view perpendicular to and aligned with the installation. A flash bulb activated by pressure sensitive tapeswitches and visible from each camera position was positioned on the impacting vehicle to indicate the instant of contact with the installation. 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 Betacam, a %-inch video camera, and still cameras were used to record and document conditions of the test vehicle and installation before and after each test. Test Vehicle A 1990 Ford Festiva was used for all four crash tests. Test inertia weight of the vehicle was 820 kg, and its gross static weight was 896 kg. The height to the lower edge of the vehicle bumper was 345 mm and it was 530 mm to the upper edge of the bumper. Additional dimensions and information on the vehicle are given in Appendix A, figure 33. The vehicle was repaired to the extent possible prior to each 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 providing a 2 to 1 speed ratio between the test and tow vehicle. Just prior to impact with the 14

21 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 it cleared the immediate area of the test site, at which time brakes were activated to bring the vehicle to a safe and controlled stop. 15

22

23 ill. CRASH TEST RESULTS n order to maximize the use of the test vehicle, the low-speed tests on both systems were performed frrst, followed by the high-speed tests. Mter each test, the test vehicle was measured to document damage and then repaired as necessary for use in subsequent tests. All tests were performed in accordance with the recommended guidelines contained in NCHRP Report 350. V-LOC SOCKET WTH U-CHANNEL SGN SUPPORT Low-Speed Test (Test ) The system evaluated in the frrst low-speed crash test was the V -Loc socket with U channel sign support. The installation was constructed as described in Section of this report. Photographs of the installation and vehicle prior to the test are shown in figures 6 through 8. Test Description The left quarter point of the vehicle impacted the U-channel support as the vehicle was traveling at a speed of 34.6 km/h and at an angle of 0 degrees with respect to the front of the sign. Movement in the U-channel post was observed s after impact. The U-channel adapter began to deform at the ground line at s, and the U-channel post began to deform at bumper height at s. At s, the U-channel post fractured at bumper height, and the vehicle lost contact with the U-channel post at s traveling at a speed of 31.4 km/h. At s, the vehicle impacted the post a second time. The top of the sign panel briefly contacted the windshield at s and then slid off to the right of the vehicle. Sequential photographs of the test period are presented in Appendix B, figure 34. Damage to Test nstallation The post-impact trajectory of the test vehicle and sign support is shown in figure 9. Damage to the test installation is shown in figure 10. The V-Loc base was pushed rearward a distance of 6.4 mm. The U-channel adaptor was lifted 38 mm out of the socket and experienced almost complete fracture and separation through the weakening holes that were initially located at the ground line or top of the socket. The U-channel sign support fractured at a height of 432 mm above the ground line. The sign panel and upper portion of the U-channel post came to rest 15.5 m down and 2.7 m to the right of the initial impact location. 17

24 Figure 6. V-Loc sign support system with U-channel post before test

25 Figure 7. Vehicle/installation geometries for test

26 Figure 8. Vehicle before test

27 Figure 9. After impact trajectory for test

28 Figure 10. nstallation after test

29 Vehicle Damage As shown in figure 11, the vehicle damage sustained during the impact was minor. There were minor scrapes and dents on the bumper and hood, the right headlight was broken, and the windshield was scraped. There was no measurable exterior vehicle crush and no deformation or intrusion into the occupant compartment. Occupant Risk Values The maximum change in velocity during the test period was 1.1 m/s. Data from the accelerometer located at the vehicle center of gravity were digitized for evaluation of occupant risk measures which were computed as follows. n the longitudinal direction, the occupant impact velocity was 1.0 m/s at s, the highest s occupant ridedown acceleration was -0.3 g from to s, and the maximum s average acceleration was -1.4 g between and s. There was no occupant contact in the lateral direction, and the maximum s average was -0.2 g between and s. These data and other pertinent information from the test are summarized in figure 12. Vehicle angular displacements are displayed in Appendix C, figure 38. Vehicular accelerations versus time traces are presented in Appendix D, figures 42 through 44. High-Speed Test (Test ) A new V-Loc socket was installed for the high-speed test of the U-channel sign support. The installation was identical to that evaluated in the low-speed test (Test ) and was constructed as described in Section of this report. Photographs of the completed installation and vehicle prior to the test are shown in figures 13 through 15. Test Description The right quarter point of the vehicle impacted U-channel support as the vehicle was traveling at speed of 99.5 km/h and an angle of 0 degrees with respect to the front of the sign. Shortly after impact, movement of the U-channel post was observed, and at s the post began to separate from the U-channel adapter. The U-channel support separated from the adapter at s, and the adapter pulled out of the ground at s. At s, the vehicle lost contact with the U-channel post as the vehicle was traveling at a speed of 96.6 km/h. The U-channel post and sign panel rotated and translated upward and at s the sign panel impacted the roof over the right rear passenger area. The vehicle lost contact with the sign panel at s while traveling at 93.5 kmlh. Sequential photographs of the impact are presented in Appendix B, figure

30 Figure 11. Vehicle after test

31 0.041 s s lld:lt ~ ~,,. ~ 33.6 m c~ STANDARD NUT, WASHER, AND BOLT V-LOCK SOCKET FOR U-CHANNEL ---DRECTON Of' TRAfFC WEDGE { GROUND LEVEL ~ll ~~ 111~ EMBEOMENTOEPTH '""" 7 ---=-111'''-111'''-~-._,,,_,,,ill N Generallnformation v. Test Agency.... Test No.... Date.... Test Article Type.... Name.... nstallation Height (m).... Size and/or dimension and material of key elements.... Soil Type and Condition.... Test Vehicle Type.... Designation.... Model.... Mass (kg) Curb.... Test nertial.... Dummy.... Gross Static.... Texas Transportation nstitute /28/96 Sign Support V-Loc Sign Support System 2.1 to bottom of panel V-Loc sign support system with steel U-channel post Standard soil, damp Production 820C 1990 Ford Festiva mpact Conditions Speed (km/h) Angle (deg) Exit Conditions Speed (km/h) Angle (deg) Occupant Risk Values mpact Velocity (m/s) x-direction y-direction No Contact THV (optional).... Ridedown Accelerations (g's) x-direction y-direction No Contact PHD (optional).... AS (optional).... Max s Average (g's) x-direction y-direction z-direction Test Article Final Rest (m) Forward Lateral Vehicle Damage Exterior VDS... 12FL1 CDC FLEN1 nterior OCD FSOOOOOOO Maximum Exterior Vehicle Crush (mm) nil Max. Occ. Compart. Deformation (mm) Post-mpact Behavior Max. Roll Angle (deg) Max. Pitch Angle (deg) Max.YawAngle(deg) Figure 12. Summary of results for test

32 Figure 13. V-Loc sign support system with U-channel post before test

33 Figure 14. Vehicle/installation geometries for test

34 Figure 15. Vehicle before test

35 Damage to Test nstallation Damage to the U-channel test installation is shown in figure 16. The U-channel adaptor and wedge were pulled out of the V-Loc socket. There was no measurable movement of the socket in the surrounding soil. The adapter separated from the U-channel support and experienced partial fracture and separation through the weakening holes. The U-channel post and sign panel came to rest 65.8 m downstream from its initial location. Vehicle Damage Damage to the test vehicle is shown in figure 17. The vehicle received minor dents to the bumper and hood, and the right front headlight was broken. Maximum exterior crush to the front bumper was 15 mm. The right rear section of the roof was damaged from contact with the sign support. The dent was 560 mm long, 700 mm wide, and 55 mm deep. Maximum deformation into the occupant compartment was 49 mm in the roof area at the right rear passenger side. Occupant Risk Values The maximum change in velocity during the test period was 1. 7 m/s. Data from the accelerometer located at the vehicle center of gravity were digitized for evaluation of occupant risk measures which were computed as follows. n the longitudinal direction, the occupant impact velocity was 0.7 m/s at s, the highest s occupant ridedown acceleration was -1.1 g from to s, and the maximum s average acceleration -0.7 g between and s. n the lateral direction, the occupant impact velocity was 0.8 m/s at s, the highest s occupant ridedown acceleration was -0.8 g from to s, and the maximum s average was -0.5 g between and s. These data and other pertinent information from the test are summarized in figure 18. Vehicle angular displacements are displayed in Appendix C, figure 39. Vehicular accelerations versus time traces are presented in Appendix D, figures 45 through

36 Figure 16. nstallation after test

37 Figure 17. Vehicle after test

38 0.000 s s s s HCJJ::t~:l " 'm 0 LV v" illctrl STANDARD NUT, WASHER, AND BOLT WEDGE ( GROUND LEVEL ~1111 N~ ttt~nl::::-" Ef.BEDMENTDEPTH "'"" 7 -::m' lm' l~!::l! - - JJ w Generallnformation N Test Agency..... Test No.... Date.... Test Article Type.... Name.... nstallation Height (m).... Size and/or dimension and material of key elements.... Soil Type and Condition.... Test Vehicle Type.... Designation.... Model.... Mass (kg) Curb.... Test nertial.... Dummy.... Gross Static.... Texas Transportation nstitute /29/96 Sign Support V-Loc Sign Support System 2.1 to bottom of panel V-Loc sign support system with steel U-channel post Standard soil, damp Production 820C 1990 Ford Festiva mpact Conditions Speed (km/h) Angle (deg) Exit Conditions Speed (km/h) Angle (deg) Occupant Risk Values mpact Velocity (m/s) x-direction y-direction THV (optional).... Ridedown Accelerations (g's) x-direction y-direction PHD (optional).... AS (optional).... Max s Average (g's) x-direction y-direction z-direction Test Article Final Rest (m) Forward Lateral Vehicle Damage Exterior VDS FR1 CDC FREN1 nterior OCD RR Maximum Exterior Vehicle Crush (mm) Max. Occ. Compart. Deformation (mm) Post-mpact Behavior Max. Roll Angle (deg) Max. Pitch Angle (deg) Max. Yaw Angle (deg) Figure 18. Summary of results for test

39 V-LOC SOCKET WTH THN-WALL ROUND TUBE SGN SUPPORT Low-Speed Test (Test ) The V-Loc socket used for testing of the thin-wall round steel tube sign supports was identical in fabrication to used for the U-channel testing. The installation of the test installation followed the procedures for the thin-wall round steel tubing described in Section of this report. t should be noted that the socket was installed with the open end of the "V'' shaped plate facing toward the direction of traffic which was 180 degrees opposite to the position used for the U-channel testing. Also, no adaptor was necessary since the round tube sign support was inserted directly into the socket. A triangular shaped wedge was used to secure the sign support inside the socket. A 0.9 m by 1.2 m aluminum sign panel was attached to the round tube support using two steel strap clamps. The distance from the ground to the bottom of the sign panel (i.e., mounting height) was 2.13 m. Photographs of the installation and vehicle prior to the test are shown in figures 19 through 21. Test Description The vehicle was traveling at a speed of km/h and an angle of 0 degrees when the right quarter point impacted the round tube support. Post movement began s after impact, and the post began to deform at bumper height at s. The post deformed around the front of the vehicle and was pulled out of the V-Loc base at s. At s, the top sign blank clamp slipped off the top of the post. The vehicle initially lost contact with the post at s while traveling at a speed of 31.7 km/h. The sign panel contacted the roof of the vehicle on the right side just above the windshield at s. The sign support subsequently came to rest on the vehicle. Sequential photographs of the test period are presented in Appendix B, figure 36. Damage to Test nstallation The post impact trajectory of the vehicle and round tube sign support are shown in figure 22. Damage to the installation is shown in figure 23. The sign support wrapped around the front end and came to rest on the vehicle. The upper steel band clamp used to attach the sign blank to the support slid off of the post. The post pulled out of the V-Loc socket, deforming the rear of the socket and the wedge. There was no measurable movement of the socket in the surrounding soil. 33

40 , ~ Figure 19. V-Loc sign support system with round tube post before test

41 Figure 20. Vehicle/installation geometries for test

42 Figure 21. Vehicle before test

43 Figure 22. After impact trajectory for test

44 Figure 23. nstallation after test

45 Vehicle Damage The vehicle received minor scrapes to the bumper, hood, and windshield. Contact with the sign panel resulted in two small dents on the front right side of the roof. There was no measurable exterior vehicle crush and no deformation or intrusion into the occupant compartment. Photographs of the vehicle after the test are shown in figure 24. Occupant Risk Values The maximum change in velocity during the test period was 1.0 m/s. Data from the accelerometer located at the vehicle center-of-gravity were digitized for evaluation of occupant risk measures which were computed as follows. n the longitudinal direction, the occupant impact velocity was 0.9 m/s at s, the highest s occupant ridedown acceleration was -0.2 g from to s, and the maximum s average acceleration -1.3 g between and s. n the lateral direction, the occupant impact velocity was -0.4 m/s at s, the highest s occupant ridedown acceleration was -0.3 g from to s, and the maximum s average was 0.3 g between and s. These data and other pertinent information from the test are summarized in figure 25. Vehicle angular displacements are displayed in Appendix C, figure 40. Vehicular accelerations versus time traces are presented in Appendix D, figures 48 through 50. High-Speed Test (Test ) A new V -Loc socket was installed for the high-speed test of the round tube sign support. The installation was identical to that evaluated in the low-speed test (Test ) and was constructed as described in Section T of this report. Photographs of the completed installation and vehicle prior to the test are shown in figures 26 through 28. Test Description The vehicle was traveling at a speed of 99.1 km/h and an angle of 0 degrees when the left front quarter point impacted the round tube support. The support post began to move s after impact, and the post began to deform at bumper height at s. The post pulled out of the V-Loc base at s, and the post pulled out of the top sign blank clamp at s. The vehicle lost contact with the post at s while the vehicle was traveling at a speed of 97.5 km/h. t was at this same time that the sign panel separated from the post. The post contacted the left front of the roof just above the windshield at s. As it continued to rotate across the roof, it impacted and shattered the sunroof at s. The post lost contact with the roof at s as the vehicle was traveling at 96.7 km/h. Sequential photographs of the test period are presented in Appendix B, figure

46 Figure 24. Vehicle after test

47 0.000 s s s s ~~m~ m o.l fimd Slgcpooitl<>o~ GROUND level / SGN Af'PROF'RATEATTACHMENT HARDWARE ROUND POST \ WEDGE-..._ ~~ _/ 't~k SOCKET FOR ROUND\SOUARE '"=111~111. ~1 ~~~~~:..:_ 127Mid - - -~BEtMifNTD"'H -=~;=-' _, ',_, '.ill +:>. Generallnformation... Test Agency.... Test No.... Date.... Test Article Type.... Name.... nstallation Height (m).... Size and/or dimension and material of key elements.... Soil Type and Condition.... Test Vehicle Type.... Designation.... Model.... Mass (kg) Curb.... Test nertial.... Dummy.... Gross Static.... Texas Transportation nstitute /29/96 Sign Support V-Loc Sign Support System 2.1 to bottom of panel V-Loc sign support system with 60-mm round tube post Standard soil, damp Production 820C 1990 Ford Festiva mpact Conditions Speed (km/h).... Angle (deg).... Exit Conditions Speed (km/h).... Angle (deg).... Occupant Risk Values mpact Velocity (m/s) x-direction.... y-direction.... THV (optional).... Ridedown Accelerations (g's) x-direction.... y-direction.... PHD (optional).... AS (optional).... Max s Average (g's) x-direction.... y-direction.... z-direction Test Article Final Rest (m) Forward Lateral Vehicle Damage Exterior VDS... 12FR1 CDC FREN1 nterior OCD FSOOOOOOO Maximum Exterior Vehicle Crush (mm) nil Max. Occ. Compart. Deformation (mm) Post-mpact Behavior Max. Roll Angle (deg) Max. Pitch Angle (deg) Max. Yaw Angle (deg) Figure 25. Summary of results for test

48 Figure 26. V-Loc sign support system before test

49 Figure 27. Vehicle/installation geometries for test

50 Figure 28. Vehicle before test

51 Damage to Test nstallation The post impact trajectory is shown in figure 29. Damage to the test installation is shown in figure 30. The post released from the V-Loc socket as designed. The release of the post resulted in some deformation to the rear of the V-Loc socket and the wedge which was used to secure the post. There was no measurable movement of the socket in the surrounding soil. The sign panel slid off the post and came to rest 787 mm from the impact point. The post was deformed at bumper height (551 mm from the bottom edge) and came to rest 40.2 m downstream from its initial location. Vehicle Damage The vehicle received minor dents to the bumper and hood. The sunroof was shattered and windshield was cracked in the upper left comer due to contact with the round tube support post. This same contacted created a dent 290 mm long, 100 mm wide, and 15 mm deep in the left front comer of the roof just above the windshield. However, there was no deformation or intrusion into the occupant compartment. Maximum exterior crush to the front bumper was measured to be only 5 mm. Photographs of the vehicle after the test are shown in figure 31. Occupant Risk Values The maximum change in velocity during the test period was 0.7 m/s. Data from the accelerometer located at the vehicle center-of-gravity were digitized for evaluation of occupant risk measures which were computed as follows. n the longitudinal direction, the occupant impact velocity was 1.2 m/s at s, the highest s occupant ridedown acceleration was -2.0 g from to s, and the maximum s average acceleration -0.8 g between and s. n the lateral direction, the occupant impact velocity was 0.9 m/s at s, the highest s occupant ridedown acceleration was 1.3 g from to s, and the maximum s average was 0.5 g between and s. These data and other pertinent information from the test are summarized in figure 32. Vehicle angular displacements are displayed in Appendix C, figure 41. Vehicular accelerations versus time traces are presented in Appendix D, figures 51 through

52 Figure 29. After impact trajectory for test

53 Figure 30. nstallation after test

54 Figure 31. Vehicle after test

55 0.000 s s s s L 142.7rn [. 40::m----l Hct00 ~ -Jo~mf-!SJllT "" _L APF>ROPR... TEATTACHMENT HAROWR GROUNO \EL \ Wf:OOE-... rv-locl< SOCKET ror ROUND\SOUARE \..._ TUSNG / ~111:..:..:.111=~1 1:..:..:.111:_:_ EMBEDMENT '" "" DEPTH - _-ll-- - -~~llc (:111~- +:o. Generallnformation '-" Test Agency.... Test No.... Date.... Test Article Type.... Name.... nstallation Height (m).... Size and/or dimension and material of key elements.... Soil Type and Condition.... Test Vehicle Type.... Designation.... Model.... Mass (kg) Curb.... Test nertial.... Dummy.... Gross Static.... Texas Transportation nstitute /29/96 Sign Support V-Loc Sign Support System 2.1 to bottom of panel V-Loc sign support system with 60-mm round tube post Standard soil, damp Production 820C 1990 Ford Festiva mpact Conditions Speed (km/h).... Angle (deg).... Exit Conditions Speed (km/h).... Angle (deg).... Occupant Risk Values mpact Velocity (m/s) x-direction.... y-direction.... THV (optional).... Ridedown Accelerations (g's) x-direction.... y-direction.... PHD (optional).... AS (optional).... Max s Average (g's) x-direction.... y-direction.... z-direction Test Article Final Rest (m) Forward Lateral Vehicle Damage Exterior VDS... 12FL1 CDC FLEN1 nterior OCD FSOOOOOOO Maximum Exterior Vehicle Crush (mm) Max. Occ. Compart. Deformation (mm) Post-mpact Behavior Max. Roll Angle (deg) Max. Pitch Angle (deg) Max. Yaw Angle (deg) Figure 32. Summary of results for test

56

57 V. FNDNGS AND CONCLUSONS SUMMARY OF FNDNGS n all tests, the V-Loc sign support system performed satisfactorily by yielding to the vehicle and then fracturing or pulling out of the socket. The detached elements did not show potential for penetrating the occupant compartment or presenting undue hazard to others in the area. There were no intrusions into the occupant compartment during any of the tests. Except for the high-speed test with the U-channel support, there were no measurable deformations of the occupant compartment. n the high speed test with the U-channel support (Test ), the maximum deformation into the occupant compartment was 49 mm measured at the passenger side edge of the roof toward the rear of the vehicle. Considering the magnitude and location of this deformation, it was not judged to have the potential for serious injury. The test vehicle remained upright and stable during and after all of the collisions. The occupant risk factors were well below the recommended values contained in NCHRP Report 350. n each test, the vehicle came to rest behind the test article and did not intrude into adjacent traffic lanes. According to the 1994 AASHTO standards, all tests were within the preferred limit for maximum change in velocity. CONCLUSONS Evaluation summaries for the low-speed and high-speed tests on the U-channel support are shown in tables 2 and 3, respectively. Evaluation summaries for the low-speed and highspeed tests on the thin-wall round tube support are shown in tables 3 and 4, respectively. n summary, the V-Loc sign support socket meets all relevant evaluation criteria for NCHRP Report 350 test designations 3-60 and 3-61 for both the U-channel and thin-wall round tube sign supports. n addition, both systems meet the change in velocity criteria contained in the 1994 AASHTO Standard. Based on these results, it is concluded that the V-Loc socket has demonstrated satisfactory impact performance when used in conjunction with a 5.95 kg/m U-channel or a 60.3 mm O.D. x 2.4 mm wall steel tube sign support. Moreover, the successful results with these supports indicates that the V -Loc socket should also perform satisfactorily with other less critical sign supports. For example, it is reasonable to assume that, based on the results of the 60.3 mm O.D. x 2.4 mm wall steel tube, round steel tubes of lesser diameter and/or lesser wall thicknesses should also be expected to exhibit acceptable impact performance. n addition, perforated square steel tube supports should also be expected to perform satisfactorily provided the yield moment of the support does not exceed that of the round steel tube which was tested under this study. 51

58 Similar reasoning can also be made in regard to the U-channel sign supports. Based on the successful results of the more critical 5.95 kg/m U-channel, the smaller 4.46 kg/m U channel should also be expected to perform acceptably with the V-Loc socket system. 52

59 U'l w Table 2. Performance evaluation summary for low-speed test on V-Loc sign support system with U-channel post, NCHRP Report test Test Agency:--Texas TransportatiOn nstitute Test No.: Test Date: 03/28/96 NCHRP Report 350 Evaluation Criteria 1 Test Results 1 Assessment 11 Structural Adequacy B. The test article should readily activate in a predictable The V-Loc sign support system performed by yielding p manner by breaking away, fracturing, or yielding. to the vehicle and then pulling out of the base. ass Occupant Risk D. Detached elements, fragments or other debris from the test The detached elements and fragments did not article should not penetrate or show potential for penetrate nor show potential to penetrate the occupant penetrating the occupant compartment, or present an undue compartment or to present undue hazard to others in hazard to other traffic, pedestrians, or personnel in a work the area. There were nci deformations or intrusions Pass zone. Deformations of, or intrusions into, the occupant into the occupant compartment. compartment that could cause serious injuries should not be permitted. F. The vehicle should remain upright during and after collision although moderate roll, pitching and yawing are The vehicle remained upright and stable during and after the collision. ~~~-[------~~ acceptable. 11 H. Occupant impact velocities should satisfy the following: Occupant Velocity Limits (m/s) Component Preferred Maximum Longitudmal occupant mpact velocity= 1.0 m/s Pass Longitudinal 3 r 5. Occup~t naedown accelerations should satisfy the followmg: 1 Occupant Ridedown Acceleration Limits (G's) _ Pass Component Preferred Maxnnum LoDgitudmal ndedown accelerallon g 1 Longitudinal Vehicle Trajectory K. Aft~r collisi.on it i~ preferable that the vehicle's trajectory The vehicle did not intrude into adjacent traffic lanes. Pass not mtrude mto adjacent traffic lanes. 11 N. Vehicle trajectory behmd the test article S acceptable. 1 1 Pass 11

60 Table 3. Performance evaluation summary for high-speed test on V-Loc sign support system with U-channel post, NCHRP Report test Test Agency: Texas Transportation nsfiliite Test No.: r.:.1. Test Date: 03/29/96 Vl of;>. ll NCHRP Report 350 Evaluation Criteria 1 Test Results 1 Assessment 11 Structural Adequacy B. The test article should readily activate in a predictable The V-Loc sign support system performed by yielding p manner by breaking away, fracturing, or yielding. to the vehicle and then pulling out of the base. ass Occupant Risk D. Detached elements, fragments or other debris from the test The detached elements and fragments did not article should not penetrate or show potential for penetrate nor show potential to penetrate the occupant penetrating the occupant compartment, or present an undue compartment or to present undue hazard to others in hazard to other traffic, pedestrians, or personnel in a work the area. There was minimal deformation into the Pass zone. Deformations of, or intrusions into, the occupant occupant compartment (49 mm) which was judged to compartment that could cause serious injuries should not be not cause serious injmy. permitted. F. -The vehicle should remain upright during and after -- The vehicle remained upright and stableduiing and L:Jcollision although moderate roll, pitching and yawing are after the collision. Pass acceptable. 11 H. Occupant impact velocities should satisfy the following: Occupant Velocity Limits (m/s) Component Preferred Maximum Longitudinal occupant impact velocity= 0.7 m/s Pass 11 1 ~ongitudm~ 1 3 r s ccup~t n edown accelerations should satisfy the followmg: 1 Occupant Ridedown Acceleration Limits (G' s) _ 1 Pass 11 1 Component Preferred Maxtmum Longttudmal ndedown acceleration g 1 Longitudinal Vehicle Trajectory K. Afte! collisi.on it i~ preferable that the vehicle's trajectory The vehicle did not intrude into adjacent traffic lanes. Pass not mtrude mto adjacent traffic lanes. 11 N. Vehicle tr.yectory behind the test article 1s acceptable. 1 1 Pass

61 Table 4. Performance evaluation summary for low-speed test on V-Loc sign support system with round tube post, NCHRP Report test TestAgency: Texas Transportation nstitute. - -Test No.: 405o31-2 TesfDate: 03729/96 V V NCHR:P Report 350 Evaluation Criteria 1 Test Results.. 1 Assessment 11 Structural Adequacy B. The test article should readily activate in a predictable The V-Loc sign support system performed by yielding p manner by breaking away, fracturing, or yielding. to the vehicle and then pulling out of the base. ass Occupant Risk D. Detached elements, fragments or other debris from the test The detached elements did not penetrate nor show article should not penetrate or show potential for potential to penetrate the occupant compartment or to penetrating the occupant compartment, or present an undue present undue hazard to others in the area. There were hazard to other traffic, pedestrians, or personnel in a work no deformations or intrusions into the occupant Pass zone. Deformations of, or intrusions into, the occupant compartment. compartment that could cause serious injuries should not be permitted. F. The vehicle should remain upright during and after The vehicle remaine<r upright and stable during and ~~~~~~~~~~+~ ~ collision although moderate roll, pitching and yawing are after the collision. acceptable. H.. ~. y..,, ' Longitudinal occupant impact velocity~ 0.9 m/s Pass Occupant Ridedown Accelerntion limits (G's) Component 1 Prefurred 1 Max:tmum Longitudinal ridedown acceleration~ -0.2 g Pass Longitudinal Vehicle Trajectory K. Afte.r collisi.on it i~ preferable that the vehicle's trajectory The vehicle did not intrude into adjacent traffic lanes. Pass not mtrude mto adjacent traffic lanes. 11 N. Vehtcle trajectory behmd the test article ts acceptable. 1 1 Pass 11

62 Vl 0\ Table 5. Performance evaluation summary for high-speed test on V-Loc sign support system with round tube post, NCHRP Report test TesfAgei1cy: Texas Transportatiorilnstlfute Test No.: Test Date: 03/29/96 NCRP Report 350 EvaluationCrTteria 1 Test Results 1 Assessm~ Structural Adequacy B. The test article should readily activate in a predictable The V-Loc sign support system performed by yielding p manner by breaking away, fracturing, or yielding. to the vehicle and then pulling out of the base. ass Occupant Risk m D. Detached elements, fragments or other debris from the test The detached elements did not penetrate nor show article should not penetrate or show potential for potential to penetrate the occupant compartment or to penetrating the occupant compartment, or present an undue present undue hazard to others in the area. There were hazard to other traffic, pedestrians, or personnel in a work no deformations or intrusions into the occupant Pass zone. Deformations of, or intrusions into, the occupant compartment. compartment that could cause serious injuries should not be permitted. L:J F. The vehicle should remain upright during and after The vehicle remained upright and stable during and collision although moderate roll, pitching and yawing are after the collision. Pass acceptable. 11 H. Occupant impact velocities should satisfy the following: Occupant Velocity Limits (m/s).... C omponen t p re fi erre d M axtmum Longitudmal occupant mpact velocity= 0.9 m/s Pass ~ongitudm~ 3 r s l. ccup?tit n edown accelerations should satisfy the followmg: l 1 Occupant Ridedown Acceleration Limits (G' s) _ Pass Component Preferred l\.1~~u1tl l Longitudmal ndedown acceleration- 1.3 g 1_1 _ Longitudinal ~~cle Traiectory K. Aft~r collis~on it i~ preferable that the vehicle's trajectory The vehicle did not intrude into adjacent traffic lanes. Pass not mtrude mto adjacent traffic lanes. 11 N. Vehicle trajectory behind the test article is acceptable. l'lhe vehicle came to rest behind the test article. 1 Pass 11

63 APPENDX A. VEHCLE PROPERTES This section provides additional dimensions and information on vehicles used for the crash tests performed under this study. 57

64

65 1:11111!:: D~ l28-2.b B&!Sf 'D.: thru.. i- \'FAR: l!ii!iic NACE: E$ttd 1AE Fl.AJD PRE!BRE: DOOME!!:: l~5h~ ',_Jil6u.1..._ ,4z ,.. N;l.; KNJP06HQN6ff8164 DOn.~ Esllflya 1'ft!: SZE 1!i5R12 uor._l... s....c """4'"'6... ENOtE JY11E! 4 qdjnd r ENCtE SZE :'! lltsr 'WSM!SO TYPE: opnoiw.. EOJFNENT:!Motloft D\TAl Tl'l't; 50th perc male ASib 76 lqj SEi\l POS11D Driver r GEQMrrRY - (rrrn) A!4BD 1: :i~c ol ZZD 8 &:lll F :'J..UO k S3C D c Bfi2 a& p a j..u5 " J~ J t~d t D ~ll " s u 40fi ZO TEST MASS - (!sl CURB NERTW.. u, 535 SlC Mz 2B ~ld u, 82& 82D ~ss STAnC Figure 33. Vehicle properties for tests through 4. 59

66

67 APPENDX B. SEQUENTAL PHOTOGRAPHS This section contains photographs taken from high speed film during the test sequence of the crash tests performed under this study. 61

68

69 0.000 s s s s Figure 34. Sequential photographs for test (perpendicular and oblique views). 62

70 0.139 s s s s Figure 34. Sequential photographs for test (perpendicular and oblique views) (continued). 63

71 0.000 s s s s Figure 35. Sequential photographs for test (perpendicular and oblique views). 64

72 0.081 s s s s Figure 35. Sequential photographs for test (perpendicular and oblique views) (continued). 65

73 0.000 s s s s Figure 36. Sequential photographs for test (perpendicular and oblique views). 66

74 0.194 s s s s Figure 36. Sequential photographs for test (perpendicular and oblique views) (continued). 67

75 0.000 s s s s Figure 37. Sequential photographs for test (perpendicular and oblique views). 68

76 s s s s Figure 3 7. Sequential photographs for test (perpendicular and oblique views) (continued). 69