高温后带粉刷层钢筋混凝土柱非线性全过程分析

Numerical Simulation on Reinforced Concrete Columns with Mortar Cover After Exposure to Fire

在前人试验研究基础上,采用ANSYS软件对4根未外抹粉刷层RC柱构件高温后的抗震承载性能进行热—力耦合模拟分析,模拟分析数据结果与试验数据结果吻合情况较好。在有限元模型得到验证的基础上,拓展外抹粉刷层RC柱高温后抗震承载性能的热—力耦合数值模拟分析,深入探讨了外抹粉刷层对RC柱承载能力的影响。计算分析表明,粉刷层可有效减少外部高温热量输入构件,构件截面温度增长受抑制,增长相对比较缓慢;粉刷层可有效提高火灾后RC柱的屈服荷载和极限荷载,减缓刚度退化;粉刷层可起到较好的保护作用,有效减轻混凝土结构的火灾损伤。

Based on previous experimental research,this text used the software ANSYS to perform coupled thermal-structural numerical analysis on the seismic performance of four RC columns without mortar cover after exposure to fire.The numerical results agree well with the experimental data.On the basis of model verification,the seismic performance of RC columns with mortar cover after exposure to fire is analyzed to investigate the impact of mortar cover on the seismic performance of RC columns.The numerical simulation shows that the mortar cover can effectively reduce external heat input to the structure,resulting in relatively slow temperature growth in the cross-section.The mortar cover can effectively increase the bearing capacity of RC columns after fire and slow down the degradation of stiffness.The mortar cover has a good protective effect on concrete components exposed to high temperatures in fires and can effectively mitigate fire damage to concrete structures.