钢筋混凝土剪力墙考虑动力效应的恢复力模型

Hysteretic model for RC shear walls considering strain rate effect

针对目前缺乏剪力墙考虑动力效应的计算模型,根据已有9片剪力墙试件拟静力和快速动力加载试验结果,提出了考虑动力效应的剪力墙恢复力模型,并编写了相应的MATLAB程序,用于对上述9个试件以及另外6个试件的拟静力和快速加载的试验结果进行模拟。计算结果显示,在地震应变率影响范围内,考虑动力效应的恢复力模型能够更为准确地描述剪力墙在快速加载下的动态性能。在此基础上,运用所提出的恢复力模型,对比分析了一单跨6层钢筋混凝土剪力墙结构在考虑应变率效应与不考虑应变率效应两种情况下的地震时程反应。结果表明,考虑应变率效应时,结构在地震作用下延性稍有降低,可能提前发生脆性破坏。因此,在进行结构弹塑性地震反应分析时应适当考虑应变率效应的影响。

Given that dynamic effects have rarely been considered in current hysteretic model for RC walls,a new hysteretic model for RC walls considering strain rate effect was proposed based on the quasi-static and dynamic loading tests of nine RC shear walls,meanwhile the corresponding MATLAB program was developed. This program was employed to simulate the hysteretic behavior of the mentioned nine specimens and six other specimens under quasistatic and dynamic loading tests. Results show that the proposed restoring force model can describe the dynamic properties of RC walls with a good accuracy in the range of seismic strain rate. Moreover,the proposed model was used to simulate the earthquake response of a single-span six-story RC structure with and without considering strain rate.Results show that ductility reduces and brittle failure occurs earlier when considering strain rate effect. Thus,the strain rate effect should be considered properly in structural elasto-plastic seismic analysis.