钢框架-RC剪力墙高层建筑结构的弹塑性全过程分析

An inelastic analysis of the overall response of high-rise frame-shear wall hybrid structures

针对结构中的钢框架,采用稳定函数单元位移模型及空间塑性铰的弹塑性模型,建立了钢框架结构节点的弹塑性增量平衡方程;针对结构中的楼板,采用三角形平面应力单元,形成了楼板节点的弹性增量平衡方程;针对结构中的RC剪力墙,采用考虑剪切及轴力影响的等效梁单元模型,利用钢筋混凝土截面M-Φ的三折线关系及假定的两杆端塑性转角增量与弹性转角增量的关系式,得到了统一的RC剪力墙结构节点的弹塑性增量平衡方程,然后,经过集成,获得了整体结构节点的弹塑性增量平衡方程。最后,通过数值算例,验证了文中方法的正确性,并得出如下结论,该类结构最薄弱部位是剪力墙底层的底部及剪力墙与钢连梁相交接的部位。

A geometric and material nonlinear analysis of a hybrid structure is presented in this paper. For the steel frame, a stability function element together with a spatial plastic hinge model is employed to formulate the elastic-plastic incremental equilibrium equations. The slab of the structure is modeled by three-node plane stress elements and the corresponding equilibrium equations are then established. Moreover, the shear walls are modeled by equivalent beam elements, including the effects of both shear and axial deformations. By doing so, the elastic-plastic incremental equilibrium equations are derived by using the tri-linear M-~ relationship for the cross section of the equivalent beam element and the relationship between elastic and plastic rotations at both element ends. As a result, the global elasticplastic increment equilibrium equations for the hybrid structure can thus be formulated. Finally, the reliability of the proposed method is verified, using the results of a numerical example from the literature. It was found that the most critically stressed locations of the structure are near the bottom of the shear wall in the first floor and the connecting ends of the steel beams with the shear wall.