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Performance Level 2 Tests on the Missouri 30 in. New Jersey Safety Shape Bridge Rail

REPORT NUMBER

TRP-03-027-91

AUTHORS

Jim Holloway, Ronald Faller, Brian Pfeifer, Edward Post

PUBLICATION DATE

1991-11-01

ABSTRACT

The Federal Highway Administration (FHWA) currently considers a concrete safety shape bridge rail substandard for the AASHTO PL-2 performance level if it does not conform with the 32 in. minimum vertical height. This situation occurs when an existing bridge deck, with an attached 32 in. bridge rail, requires an overlay. As a result of this overlay, the bridge rail must be modified or subjected to a safety performance evaluation. The Missouri Highway and Transportation Department (MHTD) has existing 32 in. standard New Jersey safety shape bridge rails on decks which need to be resurfaced with a 2 in. concrete overlay. This would reduce the vertical height above the roadway surface from the standard 32 in. to 30 in. and would also lower the vertical face of the bridge rail from 3 in. to 1 in. To evaluate the performance of this bridge rail, the Midwest Roadside Safety Facility (MwRSF) conducted three full-scale vehicle crash tests on the Missouri 30 in. standard New Jersey safety bridge rail. Test MS30-1 was conducted with an 18,011 lb single unit straight truck at 16.1 deg and 52.5 mph. Test MS30-2 was conducted with a 1,759 lb small automobile at 20.0 deg and 62.5 mph. Test MS30-3 was conducted with a 5,460 lb pickup truck at 20.0 deg and 63.5 mph. The test procedures were conducted and reported in accordance with the requirements in the National Cooperative Highway Research Program (NCHRP) Report 230. The tests were evaluated in accordance with the safety criteria in the American Association of State Highway and Transportation Officials (AASHTO) "Guide Specifications for Bridge Railings," 1989. The safety performance of the Missouri 30 in. New Jersey safety shape bridge rail was found to be satisfactory according to the AASHTO safety criteria.