为了解决SRC-RC竖向混合框架承载力和刚度的突变问题,避免形成薄弱层,共进行了7个工况的静力非线性计算,对SRC-RC竖向混合框架的抗震性能进行了分析.通过计算给出了SRC-RC竖向混合框架的基底剪力与顶点侧移曲线、极限层间侧移角及塑性铰分布.结果表明:SRC结构层数与结构总层数的比值不应小于1/3,以保证梁铰侧移机制得以实现;RC结构部分底层容易因刚度与强度突变而成为结构的薄弱层,因此适当增加RC结构部分底层或底部数层的纵筋数量,或减小与RC柱邻接的SRC柱的配钢率,可保证楼层承载力和刚度逐级递减,改善SRC-RC竖向混合框架的抗震性能.
In order to solve the mutation of loading capacity and rigidity of SRC-RC vertical hybrid frames and to avoid the formation of weak layers,the seismic performance of SRC-RC vertical hybrid frames were studied through static nonlinear analysis of seven conditions.The relationship between the bottom shear force and the lateral displacement at the top of the frame was obtained.The ultimate story displacement angle and plastic hinge distributions were also obtained.The results show that the ratio of the SRC layers to the total layers should not less than 1/3 to ensure the realization of lateral displacement of beam hinge.The weak layer may occur at the bottom layer of RC structure adjacent to SRC layer due to the mutation of rigidity and strength,and hence an appropriate increase in the number of longitudinal reinforcement at the RC columns adjacent to SRC layer or the decrease of shape steel arrangement in SRC columns adjacent to RC layer can gradually decrease the loading capacity and rigidity of the story,and improve the seismic performance of SRC-RC vertical hybrid frames.