Nonlinear behavior of steel structures considering the cooling phase of a fire

The nonlinear behavior of steel structures considering the heating and the cooling phases of a fire is investigated by the Vector Form Intrinsic Finite Element (VFIFE) method. The temperature dependent constitutive relations of steel which include strain reversal effects are adopted. The numerical model is first verified by comparing the results with the published analytical and experimental results for steel structures in the cooling phase. Several numerical examples are then fully studied to investigate the cooling behavior of steel structures. The proposed numerical model can effectively predict the nonlinear behavior of the steel structure in both the heating and cooling phases.