中文摘要：

在合理确定火灾下钢管混凝土柱受火模型的基础上，假定钢管与混凝土完全接触，采用增大混凝土比热的办法解决混凝土中温度滞后的现象，考虑高温下材料力学厦热工性能的变化特性、混凝土瞬态热应变的影响，运用有限元程序ansys，对钢管混凝土耐火性能进行理论分析，计算结果与试验结果吻合较好．此项研究为深入了解钢管混凝土柱的耐火极限和高温下的力学性能创造了务件。

英文摘要：

On the basis of the reasonable definition of CFST column＇s theoretical model, consider the phenomenon thai thermal behaviours and mechanical properties of materials vary with temperature ,adopt the finite-element method to calculate the temperature field of concrete-filled steel tubes under high temperature by considering transient thermal strain of concrete. The calculated results are in good agreement with the test results by adoption of finite element method. The work in this paper makes it possible for further researches about the fire resistance of concrete-filled steel tubular structures.