Study on Steel-concrete Composite Structure Push-out Tests Considering the Interfacial Slip Behavior

The shear capacities and shear stiffnesses of shear connections in steel-concrete composite structures were generally obtained through push-out test. However, push-out tests are time-consuming and the experimental results could be influenced by many factors. Numerical simulation method could be an efficient alternative to push-out experiment. In this study, the interface between the concrete slab and the flange of the steel beam, and the interface between the shear studs and the surrounding concretes were simulated and analyzed. The complex interfacial behavior between concrete slab and steel beam was simulated with a multiple broken line mode cohesive zone model. Then cohesive interface element was implemented through the user subroutine available in the ABAQUS software. A three-dimensional finite element model with the cohesive elements included was developed for push-out test. The load-displacement relationships, interfacial slips, and shear stress distributions were analyzed. Results indicated that tangential slips of the interface between concrete and steel parts have characteristics of uneven distribution. The proposed method could be used for the calculation of the shear capacity and shear stiffness of shear studs. The nonlinear mechanical interfacial behavior between steel and concrete materials could be successfully simulated and analyzed with the proposed cohesive zone model.