Investigation of Prefabricated Steel Truss/Bridge Deck Systems
Steel truss bridges are an efficient and aesthetic option for highway crossings. Their relatively light weight compared with plate girder systems make them a desirable alternative for both material savings and constructability. A prototype of a welded steel truss constructed with an integral concrete deck has been proposed as a potential alternative for accelerated bridge construction (ABC) projects in Montana. This system consists of a prefabricated welded steel truss topped with a concrete deck that can be cast at the fabrication facility (for ABC projects) or in the field after erection (for conventional projects). To investigate possible solutions to the fatigue limitations of certain welded member connections in these trusses, bolted connections between the diagonal tension members and the top and bottom chords of the truss were evaluated. In this research, both a conventional cast in place deck system and an accelerated bridge deck system (cast integral with the truss) were evaluated for the bolted/welded steel truss bridge.