PARTIAL INTERACTION SHEAR FLOW FORCES IN SIMPLY SUPPORTED COMPOSITE STEEL-CONCRETE BEAMS

Most existing codes simply limit the shear stress range of stud shear connectors in composite steel-concrete beams to prevent the fatigue failure of studs, and the shear stress range is determined on the basis of a full interaction assumption, which ignores the effects of slip between steel and concrete. However, this hypothesis would overestimate the shear stress range, thereby resulting in the misestimate of the fatigue behaviours of studs. This study herein proposes a method to determine the interface shear flow under either a moving concentrated load or uniform load on the basis of the partial interaction assumption, which considers the effects of slip. Moreover, the interface shear flow, including the shear range and shear peak, under general loading can be predicted using the superposition of moving the concentrated load and uniform load. Furthermore, this method is simplified according to a practically possible range of parameters and is further validated by the finite element method (FEM) model in the case of composite beams with uniformly and non-uniformly distributed shear studs. Finally, a case study is performed using the proposed method and the existing methods to predict the shear stresses and the fatigue life of studs. The results show that the proposed method can provide more accurate and reliable predictions.