Modelling of demountable steel-concrete composite connections: Validation of finite element model and parametric study

Abstract

A three-dimensional finite element modelling and parametric analysis of a composite connection having prefabricated concrete slabs and preload bolted shear connectors are presented in this study. The load-slip relationship for this type of shear connection subjected to monotonically loading with the effect of different parameters including bolted shear connector size, bolt grade, hole size in precast concrete slab and steel beam top flange, concrete strength, and bolt preloading force is studied by means of ABAQUS software. A finite element model of the composite connection considering the non-linearities of the geometry, interfaces between the components, and materials is developed and verified against the results of the experimental study. An extensive parametric study is conducted, and the influences of different parameters on the structural behaviour of demountable steel-concrete composite shear connection are discussed in detail. In addition, a comparison of the estimated values obtained from design equations proposed by current standards, including EC4 and AISC for headed stud shear connectors, and the design recommendations provided in other studies for bolted shear connectors are conducted. According to the calculation result, the accuracy of different design methods is evaluated. Finally, a regression analysis of the data produced by the FE analysis has been employed to propose a new design equation to determine the ultimate strengths for the post-installed preload bolt shear connectors. It is concluded that the ultimate shear load capacity values predicted by EC4 and AISC provisions for composite connections having prefabricated concrete slabs and preload bolted shear connectors found to be relatively less accurate but conservative.