Research on the fire resistance design of high-strength steel hollow columns under axial compression.

Based on our completed experimental research, the fire resistance of Q550 high-strength steel (yield strength of f y = 550 N/mm2) hollow columns under axial compression is explored by a finite element numerical simulation and theoretical analysis. First, an accurate analysis model of high-strength steel columns under fire exposure is established using ABAQUS software, and a numerical simulation analysis is carried out. Based on verified finite element model, a parametric analysis of the fire resistance of high-strength steel columns is conducted. The effects of the section area A , section height-thickness ratio H / t , section height-width ratio H / B , overall bending defect amplitude e 0 , slenderness ratio λ and load ratio n on the fire resistance of high-strength steel columns are investigated. Finally, based on the parametric analysis results and different limit state judgement criteria, the calculation formulas for the critical temperature T cr and maximum axial displacement u max of Q550 high-strength steel columns with rectangular sections under axial compression are proposed. The correctness of the formulas is verified by comparing the calculation results with the test results. The research of this paper provides a theoretical basis for improving the fire resistance design of high-strength steel columns at elevated temperatures, and greatly promote the healthy development and good application of high-strength steel in structural engineering applications. [ABSTRACT FROM AUTHOR]