FULL-SCALE VEHICLE CRASH TESTS OF LUMINAIRE SUPPORTS

A FEDERAL HIGHWAY ADMINISTRATION (FHWA) NOTICE - NOVEMBER 16, 1970 (TO - 20) - PERMITTED A PENDULUM TEST TO BE SUBSTITUTED FOR A VEHICLE CRASH TEST; THE ALLOWABLE MOMENTUM CHANGE FOR PENDULUM TESTS IS SET AT 400 LB - SEC. THIS PAPER DESCRIBES THE ADDITIONAL TESTING (LS 1 - LS9) THAT WAS REQUIRED FOR A COMPARISON OF LUMINAIRE SUPPORTS BETWEEN VEHICLE AND PENDULUM TESTS. THE LUMINAIRE SUPPORTS USED IN THESE TESTS WERE MOUNTED ON A 24 SQ. IN BY 2 IN. THICK BASE PLATE THAT WAS IN TURN RECESSED INTO AND BOLTED TO A RIGID CONCRETE FOUNDATION. EIGHT OF THE LUMINAIRE SUPPORTS TESTED WERE MADE OF ALLOY 6063-T6 ALUMINUM WITH ALLOY 356 CAST ALUMINUM SHOE BASES WELDED ON. IN 7 TESTS A DUMMY, RESTRAINED BY A STRAINGAUGED SEAT BELT TO DETERMINE SEAT- BELT FORCES, OCCUPIED THE DRIVER'S SEAT. FOR TESTS LS1 THROUGH LS-6, 1963 PLYMOUTHS WERE USED, FOR TEST LS-7 A 1957 CADILLAC, AND FOR TESTS LS-8 AND 9 1963 CHEVROLETS. THE VALUES OF MOMENTUM CHANGE WERE CALCULATED FROM HIGHSPEED FILM AND ACCELEROMETER DATA. INITIAL SPEED OF THE VEHICLE WAS CALCULATED OVER A DISTANCE OF ABOUT 4 FT PRIOR TO CONTACT WITH THE LUMINAIRE SUPPORT. FINAL SPEED WAS CALCULATED OVER A SIMILAR DISTANCE IMMEDIATELY AFTER THE VEHICLE LOST CONTACT WITH THE LUMINAIRE SUPPORT. THE MOMEN- TUM CHANGE WAS FOUND BY MULTIPLYING THE VEHICLE MASS BY THIS CHANGE IN SPEED. MOMENTUM LOSS WAS ALSO CALCULATED BY DETERMINING THE SPEED CHANGE FROM THE ACCELEROMETER TRACES. INTEGRATION OF THESE ACCELEROMETER TRACES GIVES CHANGE IN SPEED, WHICH IS AGAIN MULTIPLIED BY VEHICLE MASS TO GIVE CHANGE IN MOMENTUM DURING THE COLLISION. REASONABLE AGREEMENT WAS FOUND BETWEEN THE TWO METHODS OF DETERMINING CHANGE OF MOMENTUM. HOWEVER, THE VALUES OBTAINED FOR MOMEN- TUM CHANGE WERE EITHER BOTH BELOW OR BOTH ABOVE THE 1,100 LB-SEC CRITERION. THE MAXIMUM VARIATION BETWEEN THE TWO MO- MENTUM CHANGES FOR A PARTICULAR TEST WAS 125 LB-SEC FOUND IN TEST LS-8. THE AVERAGE DIFFERENCE IN TWO METHODS OF ANA- LYZING THE NINE TESTS WAS 64 LB-SEC, WITH SEVEN OF THE NINE SHOWING A DIFFERENCE OF 90 LB-SEC OR LESS.

Media Info

  • Media Type: Print
  • Features: Figures; References; Tables;
  • Pagination: pp 52-65
  • Monograph Title: Traffic safety barriers, lighting supports and dike slopes
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00203656
  • Record Type: Publication
  • Report/Paper Numbers: No 386 pp
  • Files: TRIS, TRB
  • Created Date: Oct 9 1972 12:00AM