BEHAVIOR OF ADHESIVELY BONDED CONCRETE-GRAPHITE EPOXY COMPOSITE BRIDGE GIRDERS/

The focus of this paper is on the behavior of composite bridge girders constructed from carbon fiber reinforced plastic sections and concret e slabs. The study examined four-point bending of three beams, one bar e, I-type, graphite/epoxy beam, and two constructed from concrete slab and graphite/epoxy sections. The concrete slab and graphite/epoxy sec tion were adhesively bonded and no shear connectors were used. All thr ee beams are approximately one-eighth scale models of bridge girders. The sections are geometrically symmetric and have the same symmetric l amination schemes. Theoretical and experimental studies were performed on the bare I-sections to develop basic understanding of the bending behavior. The analyses and tests were then extended to the composite g irders. The theoretical and experimental results for the failure loads were in close agreement. It was found that the slip at the interface of the concrete slab and the graphite/epoxy beam had minor effects on the failure load, but it significantly reduced the stiffness of the co mposite sections.