Guardrail and Guardrail Terminals Installed Over Curbs [Phase I]

US Transportation Collection2000PDFOtherPolivka, Karla A.Faller, R.K.Sicking, D.L.Rohde, J. R.Reid, J. D.Holloway, J.C.Midwest Roadside Safety FacilityMidwest States Regional Pooled Fund ProgramUnited States. Department of Transportation. Federal Highway AdministrationMidwest States Regional Pooled Fund ProgramNebraskaCrash testsCurbsDesignGuardrail terminalsGuardrailsPickup trucksPostsSpacingSpeedSPR-3(017)MwRSF Research Report No. TRP-03-83-99SPR-3(017)Final Report 1997 - 2000A barrier system was developed for installation where W-beam is placed over curbs. The guardrail design was constructed with a 2.66-mm (12-gauge) thick W-beam rail totaling 53.34 m in length. The W-beam rail was supported by twenty-five W150 x 13.5 steel posts, each measuring 1,830 mm long, and four standard BCT posts, each measuring 1,080 mm long. Post spacings were 1,905 mm on center. The concrete curb was a type "G" curb that measured 203 mm wide x 102 mm high x 19.05 m long. The research study included full-scale vehicle crash testing and live-driver curb testing, using a 2000-kg pickup truck. The full-scale test, impacting at a speed of 103.2 km/hr and an angle of 24.5 deg, was unsuccessful because the barrier system failed at the splice at post no. 12. The three live-driver curb tests, impacting at a speed of either 64 km/hr or 100 km/hr and an angle of 25 deg, helped to determine the curb, tire, and suspension interaction to use in future simulation work. The safety performance of the long-span barrier system was determined to be unacceptable according to the Test Level 3 (TL-3) evaluation criteria specified in NCHRP Report No. 350, "Recommended Procedures for the Safety Performance Evaluation of Highway Features."97