Finite element modeling of push-out tests for large stud shear connectors

An accurate nonlinear finite element model of the push-out specimen has been developed to investigate the capacity of large stud shear connectors embedded in a solid slab. The material nonlinearities of concrete, headed stud, steel beam and rebar were included in the finite element model. The damage and failure were included in the material model for the headed stud to accurately obtain the ultimate strength of the stud connector. The capacity and ductility of the connection, the load–slip behaviour and failure mode of the headed stud were predicted. The results obtained from the finite element analysis were verified against experimental results of other researches. An extensive parametric study was conducted to study the effect of the changes in stud diameter and concrete strength on the capacity and behaviour of the shear connection. The capacity and ductility of the shear connection obtained from the finite analysis were compared with those specified in EC4 and AASHTO LRFD. It is observed that the AASHTO LRFD specifications overestimated the capacity of the large stud shear connectors, whereas the design rules specified in Eurocode-4 were generally conservative for stud diameters of 22, 25 and 27 mm, and unconservative for diameter of 30 mm. The ductility of the large stud shear connectors is sufficient for practical application in composite bridges.