Performance-based fire resistant design for concrete-filled HSS columns

The use of concrete filling offers a practical alternative for achieving the required stability of steel Hollow Structural Section (HSS) columns under fire conditions. However, the current prescriptive-based approach, has a number of constraints that in many applications restrict the utilization of concrete filling for achieving the required fire resistance. To overcome such constraints, a performance-based methodology for fire resistance design is presented in this paper. A set of numerical simulations were carried out to investigate the effect of realistic fire scenarios, loading, and stability based failure criterion on the fire resistance of concrete filled HSS columns. Results from the parametric studies show that fire scenario and load level have significant influence on the resulting fire resistance. It is demonstrated that by adopting a performance-based approach, it is possible to show that concrete filled HSS columns can provide fire resistance sufficient to withstand complete compartment burnout, while maintaining structural integrity.