钢筋混凝土框架-剪力墙结构基于位移的抗震设计方法

根据钢筋混凝土框架-剪力墙结构的特点,将其性能划分为使用良好、保证人身安全和防止倒塌三个水平,并用层间位移角限值予以量化。以作用倒三角形水平分布荷载的等截面弯剪悬臂杆的侧移曲线作为其初始侧移模式。对于使用良好性能水平,将侧移曲线上反弯点对应的楼层处的层间位移角刚好达到相应限值时的侧移曲线作为目标侧移曲线,据此计算等效单自由度体系的等效参数以及原结构的基底剪力和各质点的水平地震作用。对于保证人身安全和防止倒塌的性能水平,根据Pushover曲线与需求曲线的关系对结构予以调整,使结构满足这两个性能水平的要求。

RESEARCH ON DISPLACEMENT-BASED SEISMIC DESIGN METHOD OF REINFORCED CONCRETE FRAME-SHEAR WALL STRUCTURES

According to the characteristic of reinforced concrete frame-shear wall structure,the seismic performance level is divided into three levels: serviceability, life-safety, and collapse prevention. The three levels are qualified with storey drift ratios. Applying the inverted triangular distribution of lateral force to the cantilever column of constant section, and the displaced shape of the column is regarded as the initial mode of lateral displacement. For serviceability, the displaced shape, which storey drift ratio of the floor level at point of contraflexure on the initial mode of lateral displacement is equal to limit of the storey drift ratio, may be seen as target displacement mode. Based on the target displacement mode of frame-shear wall structure in the serviceability performance level, the equivalent parameter can be obtained. Thus, the base shear V_b and horizontal earthquake force F_i at each floor of the building can be determined. Finally, the designed structure is analyzed with nonlinear static analysis method and the design is adjusted by the pushover analysis result until it is satisfied.