Numerical analysis on the temperature distribution of steel tube reinforced concrete columns subjected to 3-side heating

摘要

The temperature fields of steel tube filled concrete columns are analyzed by a nonlinear FEM model in the paper. The theoretical results are validated by relative test results, and a good agreement is obtained. Using the theoretical models, the influencing laws of temperature rising time; section perimeter; steel reinforcement ratio and sectional core area ratio on temperature field of STRC subjected to 3-side fire are further discussed. By above parametric analysis, it has been found that the effects of heating time, sectional dimension and sectional core area ratio on temperature field are significant, but steel ratio has very little effect on temperature both of steel tube and of section surface.