Numerical studies on headed shear studs under elevated temperatures

A shear connection between the steel beam and concrete slab determines the stability of a composite beam. A three-dimensional thermo-mechanical coupled model was developed incorporating an explicit dynamic method and a concrete damaged plasticity model to investigate shear stud behavior at high temperatures. The plasticity parameters of the concrete model were derived using triaxial compressive experimental data with different temperatures. A nonlinear temperature profile was modelled during the entire heating process, and its value was employed for the stress analysis. The reliability of the developed model was verified with the push-out test data both at ultimate and fire limit states. This investigation has revealed that the stud resistance reduces, and also its shearing position varies from the stud shank to weld collar in correlation with the temperature. Calibration of the result indicates a lack of a conservative figure within EC4 when compared to the modelling and experimental data.