BEHAVIOUR OF STEEL-CONCRETE COMPOSITE GIRDER BRIDGE

Abstract

In composite members two or more elements are joined together so that they are stronger, stiffer and more ductile than the sum of the individual components which are now commonly used in modern construction practice. The concrete deck slab and steel section are connected together in steel-concrete composite girder bridge using shear connectors to transfer the longitudinal shear. Due to deformable nature of the connectors relative slip occurs at the interface of steel and concrete which leads to partial interaction. This makes the behavior of composite structures complex, so that the most of the composite structures are designed assuming no slip or full interaction. Therefore it is necessary to study the true behaviour of the composite section. The main objective of the present work is to compare various existing linear partial interaction theories among themselves as well as with the proposed nonlinear interlayer model, to predict the slip and deflection. Grillage analysis has been carried out using Staad Pro software assuming the perfect bonding and is to be compared with the proposed nonlinear interlayer theory with reference to deflection in composite girder bridge. Various parametric studies will be carried out, considering grade of concrete, degree of shear connection, span length and spacing of shear connectors, to find the influence of parameters on the slip and deflection of partially composite section for various existing linear partial interaction theories as well as the proposed nonlinear interlayer model.