Buckling and critical temperatures of box-section steel columns in fire considering dynamic effect
The buckling and critical temperatures of box-section steel columns in fire were studied by parametric analysis.The finite element model of the restrained steel column was validated by test data in literatures considering the rotational restraint stiffness ratio,axial restraint stiffness ratio and load ratio.The results show that the buckling temperatures obtained by the static analysis and explicit dynamic analysis are almost the same,and the critical temperatures obtained by static analysis are slightly lower than those obtained by explicit dynamic analysis,and the difference is within 30℃.The buckling and critical temperatures both increase with the increase of rotational restraint stiffness ratio.Besides,the rotational restraint stiffness ratio has greater influence on the critical temperature than that on the buckling temperature.In addition,with the increase of axial restraint stiffness ratio and load ratio,both the buckling and critical temperatures decrease significantly.Based on the analysis results of the current study and the existing calculation formulas about buckling and critical temperatures in literatures,new calculation formulas for buckling and critical temperatures of steel columns are proposed,respectively.The prediction results of the proposed calculation formulas are in good agreement with the analysis results.The validity of the proposed formulas of buckling and critical temperatures is further verified by test data.The comparison results show that the proposed formulas can well predict the buckling and critical temperatures of steel columns.
restrained steel columnfiredynamic effectbuckling temperaturecritical temperaturecalculation formula
万方数据
维普
