Thermal creep effect on the behavior of shear tab connections due to fire temperatures

This study investigates the effect of thermal creep of steel on the behavior of shear tab beam-column connections due to fire temperatures. FE simulations are first developed under fast steady-state temperature conditions to study the behavior of the shear tab connections at different temperatures and validated against experimental data available in the literature. Parametric studies are performed to investigate the impact of major geometric parameters on the behavior of the shear tab connections during fire temperatures with and without creep effect. Then, creep effect is explicitly included in the FE models under steady-state temperature conditions to study the time-dependent deformations of shear tab connections when applied forces and temperatures are kept constant. Also, isochronous force-rotation curves are developed to better understand the time effect on the strength and rotational capacity. Results from the simulations and parametric studies show that the connection experiences additional rotation/displacement and a change in failure mode is observed when the effect of thermal creep is included in predicting the response of the shear tab connections. These results clearly indicate the importance of including creep in predicting the response of shear tab connections subjected to fire temperatures and its effect on the behavior.