The results of testing and evaluation of the current wyoming steel tube-typebridge railing system and the development, testing, and evaluation of a box-beam guardrail transition for use with this bridge railing system are presented. The crash test results indicate that both the bridge railing and the box-beam guardrail transition retrofit design satisfy the guidelines set forth in nchrp report 230. The steel tube-type bridge railing is currently on the approved list of bridge railings for use on federal-aid projects. The box-beam guardrail transition is currently under review by fhwa for approval. The key advantages of this steel tube-type bridge railing are that it is aesthetically pleasing and that it allows the traveling public views of surrounding areas from the bridge deck. Its initial and maintenance costs are competitive. This type of railing does not present problems with drifting snow or clearing snow from roadways, commonly associated with concrete barriers. These problems are what prompted the development of the transition treatment so that the box-beam guardrail could be used in conjunction with the steel tube-type bridge rail. This paper appears in transportation research record no. 1258, Roadside safety 1990.
Abstract