变刚度框架-摇摆墙结构参数模型研究

Research on a parameter model of frame-rocking wall structures with variable stiffness

框架-摇摆墙是自复位结构体系中重要的结构形式之一。既有对其抗震性能的研究中,大多通过分布参数模型来模拟框架-摇摆墙结构。该模型由剪切梁和弯曲梁及连接上述两者的无限根刚性链杆组成。其中,剪切梁和弯曲梁分别代表框架与摇摆墙。基于工程实际情况,本研究对既有的分布参数模型进行了改进:(1)采用集中质量模型模拟框架结构;(2)考虑框架沿竖向刚度的变化;(3)框架与摇摆墙仅在楼层处连接;(4)在摇摆结构底层引入反映基础与摇摆墙之间约束强弱的转动弹簧。基于此,文中提出了一种模拟变刚度框架-摇摆墙结构的离散-连续参数模型。计算结果表明:与既有的参数模型相比,改进后的模型能更真实、合理地反映框架-摇摆墙结构的受力性能。

Frame-rocking wall structures are one of significant forms in self-centering structural systems.Typically,a Distributed Parameter Model(DPM) is employed to simulate frame-rocking wall structures to study their structural performances.The DPM consists of a shear beam and a bending beam connected by an infinite number of rigid links.The shear beam and the bending beam represent the frame and the rocking wall,respectively.In this paper,the DPM has been upgraded based on practical engineering situations.Specifically,(1) A lumped-mass model is utilized to simulate the frame;(2) The change of vertical stiffness of the frame is considered;(3) The frame and the rocking wall are only connected via the rigid links at the positions of the floors;(4) At the bottom of the rocking wall,a rotational spring reflecting the constraint condition between the foundation and the rocking wall is adopted.In the light of the above,a Discrete Continuum Model(DCM) is proposed to simulate frame-rocking wall structures with variable stiffness.The results show that the DCM can demonstrate the mechanical properties of frame-rocking wall structures more realistically and reasonably compared with the DPM.