中文摘要：

基于三维热分析实体元和三维梁单元,利用Visual C＋＋编制钢筋混凝土柱火灾试验数值模拟程序RCSSCF,模拟火灾试验时柱式构件中部受火的情况,并考虑了轴力的二阶效应.研究结果表明,采用的温度场求解的子结构技术,适用于炉膛内外交界区域及钢筋混凝土结构梁柱节点的三维温度场的求解.在保持计算精度不变的前提下,该求解方法能够明显减少计算时间.材料本构关系加卸载对柱耐火极限的预测精度影响不大,但对升温后期轴向变形的预测结果影响较大.在进行钢筋混凝土结构的抗火性能研究时,需要考虑材料本构关系的加卸载.

英文摘要：

An computer program RCSSCF based on 3-dimensional thermal solid element and 3-dimensional beam element is developed using Visual C＋＋ to predict the real circumstance that only the middle parts of the column is exposed to fire in the fire test. A solution for the thermal analysis using substructure is suggested and the second-order effect of axial force is considered in the program. The reliability of the program is validated using experimental results. The results show that： （1） a thermal analysis using substructure can save calculation consumption greatly. （2） the loading and unloading of material stress-strain relationships, have little influence on the precision of predicting fire resistance, but have significant influence on the axial deformation at the later stage of temperature rising. During the research of fire resistance of reinforced concrete structures, the loading and unloading of material stress-strain relationship would be considered.