中文摘要：

对IS0834标准火灾作用后钢筋混凝土柱的剩余承载性能及方形柱剩余承载力的实用计算方法进行了研究。结合高温后混凝土和钢筋的本构模型及虚梁法，建立了火灾作用后钢筋混凝土柱剩余承载力的数值分析模型，并编制了相应的程序CAFIRE，程序考虑了轴力的二阶效应。利用程序分析了相关参数对标准火灾作用后钢筋混凝土方形柱剩余承载力的影响规律。针对不同受火时间、计算长度、截面尺寸、荷载偏心率、配筋率和荷载角等情况，共进行了2700种工况下钢筋混凝土方形柱剩余承载力分析。在计算结果的基础上，定量给出了标准火灾作用后钢筋混凝土方形柱剩余承载力的实用计算方法。最后利用程序比较了不同受火时间后相同横截面面积、相同配筋率、不同截面形状混凝土柱的剩余承载力。

英文摘要：

The residual bearing mechanism of reinforced concrete （RC） columns and the practical calculation method for the residual strength of square columns after exposure to ISO834 standard fire are investigated. Combining the constitutive model of concrete and its reinforcements after exposure to fire and the conjugate method, the numerical model for the calculation of residual strength of RC columns after exposure to fire is proposed and the corresponding program CAFIRE is developed. The second-order effect of the axial force is considered in the study. Using the numerical program CAF1RE, the influence of several correlative parameters on the residual strength of RC columns with square cross section after exposure to ISO834 standard fire is analyzed. 2700 RC columns with square cross section are selected for residual strength analyses. Different fire exposure times, effective lengths, sectional dimensions, load eccentricity ratios, reinforcement ratios and load angles are considered in the analyses. Based on the simulation results, a practical calculation method is proposed for the residual strength of RC square columns. Moreover, the residual strength of RC columns with the same sectional area and reinforcement ratio but with different shape of cross section is compared using the program.