Concrete modeling in finite element push-out test simulations

Push-out tests are commonly used to investigate the shear performance of mechanical connectors applicable in steel-concrete composite beams. These tests can be complemented by numerical finite element simulations to reduce the need for extensive experimental testing. After validation against experimental results, numerical models could be used for additional analysis and parametric studies. The development of finite element models of push-out tests requires special attention to be put on modelling concrete behaviour, especially if concrete failure is the dominant failure mode. The concrete damage plasticity (CDP) models, combining plasticity and damage mechanics to represent the nonlinear behaviour of concrete, are commonly applied. This paper summarises and presents four different CDP models that have been successfully used by researchers in finite element simulations of push-out tests. The applicability of different models has been discussed in the specific case of shear connection with headed studs in profiled steel sheeting with a varied angle between profiled sheeting ribs and the beam. Results of comparative analysis are presented, indicating a significant influence of the applied CDP model on the response of push-out specimen. The best match between experimental and numerical results is accomplished by implementing the material model proposed by Pavlović with calibrated input parameters. Nevertheless, the applicability of each CDP model depends on the specific problem that is being analysed and therefore should be carefully approached.