Continuous Shear Connectors in Bridge Construction

Abstract

Continuous shear connectors offer an upcoming solution for composite beams. They are characterized by a high initial stiffness, bearing capacity and ductility. With their use new and economic construction methods have been invented, e.g. the PreCoBeams (Prefabricated Composite Beam). PreCoBeams are composite beams associating T-sections acting as tension member with a concrete top chord acting as compression member. Steel parts are generally obtained from rolled steel profiles that are longitudinally cut, with a special shape, in two T-sections. The shape of the cut allows for shear transmission between steel and reinforced concrete, which is continuous regarding the steel. In general, prefabricated composite bridge elements are produced, consisting of the steel T-section with a precast first phase concrete flange. The second phase concrete layer is then completed in-situ after placing of the bridge elements on the abutments. These PreCoBeam bridges are very economic in design and construction, though the main market drawback for PreCoBeams is the missing design approach for the shear connection. This paper introduces the static and fatigue design of continuous shear connections used for PreCoBeams derived from recent research activities; however the focus is on the steel design.