Finite element model for the creep analysis of composite steel- concrete push tests

Composite steel-concrete structures are employed extensively in modern high rise buildings and bridges. Even though the combination of steel and concrete enhances the strength and stiffness of composite beams, the time-dependent behaviour of concrete may weaken the strength of the shear connection. When the concrete loses its strength, it will transfer its stresses to the structural steel through the shear studs. This behaviour will reduce the strength of the composite member. This paper presents the development of an accurate finite element model using ABAQUS to study the behaviour of shear connectors in push tests incorporating the time-dependent behaviour of concrete. The structure is modelled using three-dimensional solid elements for the structural steel beam, shear connectors, concrete slab and profiled sheeting. The finite element analyses indicated that the slip ductility, the strength and the stiffness of the composite member were reduced with respect to time. Further experiments to validate the models presented herein will be conducted and reported at a later stage.