考虑退化、捏拢和双向耦合效应的等强度延性需求谱

发布时间：2018-06-06 10:52

本文选题：双向地震激励 + 滞回模型　；参考：《振动与冲击》2017年11期

【摘要】：传统的等强度延性需求谱通常难以有效地考虑强度退化、刚度退化、捏拢效应以及双向恢复力耦合效应的影响。鉴于此,基于双轴Bouc-Wen-Baber-Noori模型,建立了双向地震激励作用下单质点双自由度体系非弹性地震反应谱的基本方程,并定量分析了强度退化、刚度退化、捏拢效应和双向恢复力耦合效应对结构地震延性需求的影响,进而分别建立了等强度延性需求的均值谱和标准差谱的预测方程。分析结果表明:强度退化、刚度退化和捏拢效应会增大结构的地震延性需求;双向恢复力的耦合效应对地震延性需求的影响,取决于结构沿两个主轴方向地震耗能能力的相互竞争;退化、捏拢和耦合效应会明显增大结构地震延性需求的标准差,且非线性程度越高,随机性表现越明显;随着结构沿两个主轴方向自振周期的增加,等强度地震延性需求的均值和标准差均逐渐减小。
[Abstract]:The influence of strength degradation, stiffness degradation, pinch effect and bidirectional restoring force coupling effect are usually difficult to be effectively considered in the traditional demand spectrum of equal strength ductility. In view of this, based on the biaxial Bouc-Wen-Baber-Noori model, the basic equations of inelastic seismic response spectrum of two-degree-of-freedom system with single mass point under biaxial earthquake excitation are established, and the degradation of strength and stiffness is quantitatively analyzed. The effects of pinch effect and bidirectional restoring force coupling effect on the seismic ductility demand of structures are discussed, and the prediction equations of mean and standard deviation spectra of iso-strength ductility demand are established respectively. The results show that strength degradation, stiffness degradation and squeezing effect will increase the seismic ductility demand of the structure, and the coupling effect of bidirectional restoring force will affect the seismic ductility demand. It depends on the mutual competition of the seismic energy dissipation ability of the structure along the direction of the two main axes, the degradation, pinch and coupling effect will obviously increase the standard deviation of the seismic ductility demand of the structure, and the higher the degree of nonlinearity, the more obvious the randomness is. With the increase of the natural vibration period along the two main axes, the mean value and the standard deviation of the ductility demand for iso-intensity earthquakes decrease gradually.
【作者单位】：同济大学上海防灾救灾研究所;广西大学土木建筑工程学院工程防灾与结构安全教育部重点实验室;
【基金】：国家自然科学基金(51368006) 广西自然科学基金重大项目(2012GXNSFEA053002)
【分类号】：TU352.11

【相似文献】