加载速率对钢筋混凝土结构损伤的影响

摘要

Based on the results of the dynamic experiment of RC beams and columns,the damage evolution equations of RC beam and column,considering the loading rate effect,are presented respectively in order to study the damage of RC (reinforced concrete) structures in this paper.The numerical results are compared with the test results to verify the rationality of these equations.An improved restoring force model of RC members considering loading rates is presented and the strain,strain rate,damage of a 6-storey model for RC frame is numerically analyzed.The results show that:the damage evolutions of the members are similar,and the damage develops rapidly at the peak acceleration.The damage of the beam is 0.06 while the damage of the column is 0.17,which states that the damage of column is larger than that of beam.The damage model presented in this paper is proved to be proper to simulate the damage of RC structures.%目的 为探讨钢筋混凝土结构的动态损伤特性,进一步研究钢筋混凝土高层建筑结构连续倒塌破坏机理.方法 在钢筋混凝土梁柱构件动力特性试验基础上,分析钢筋混凝土梁柱构件的损伤,分别提出考虑加载速率影响的梁、柱构件的损伤演化方程,介绍一种改进的考虑加载速率影响的构件恢复力模型,并对一座6层3跨的钢筋混凝土框架结构模型进行地震作用下动态模拟,分析结构中主要构件的应变、应变率和损伤随时间的变化.结果 通过与试验结果对比,验证了笔者提出模型的有效性.通过数值模拟,得到梁的损伤值为0.06,柱的损伤值为0.17.结论 构件的损伤发展规律相近,且在地震动加速度峰值附近损伤迅速发展;柱的损伤大于梁的损伤.笔者提出的损伤模型能有效地模拟钢筋混凝土结构的损伤特性.