含少量抗震墙的RC框架结构位移限值探讨

Discussion on the RC Frame Inter-story Drift Index for Buildings with Few Shear Walls

基于位移的抗震设计是实现基于性能的抗震设计的最有效途径,我国规范对不同结构、不同抗震等级的建筑提出了相应的位移限值。但是随着人们对建筑功能的要求提高,含少量抗震墙的框架结构越来越多,此类结构的层间位移控制限值问题一直困扰着结构工程师。文中以实际工程计算为例,探讨了如何分类含少量抗震墙的框架结构,建议此类结构在多遇地震作用下,可以允许抗震墙出现一定的开裂,其抗侧刚度出现一定退化。结合ABAQUS有限元分析软件得到的剪力墙刚度退化规律,利用ETABS有限元分析软件对少墙框架结构进行整体分析,提出了此类结构的层间位移角的控制方法。

Displacement-based seismic design is one of effective performance-based seismic design methods. Design codes specify the displacement limits for various structures in China. For different functional requirements, there are more and more RC frame buildings with few shear walls. How to control the seismic displacement of this type of structures becomes a problem for structural engineers. A new method is proposed to classify frame structures with few shear walls. The shear walls in these structures are allowed to crack under frequently-occurred earthquakes, and therefore, existing stiffness degradation. Based on the ABAQUS and ETABS finite element analyses, the limit for inter-story displacement of frame structures with few shear walls was summarized.