【摘要】 针对柱顶隔震结构,提出考虑P-Δ效应动力响应的免迭代计算方法,分析P-Δ效应对柱顶隔震结构响应的影响。由于隔震层处的层间位移较大,当受到的轴力较大时,二阶效应不容忽视。隔震支座采用双线性模型,构造水平力偶代替结构轴向力形成的弯矩,并在隔震层处做了特殊处理,使得隔震层处的附加弯矩能够传递到下部结构。这样在计算结构的非线性响应时,相当于结构的刚度矩阵在原来的基础上增加了一个几何刚度矩阵,从而避免了迭代运算。研究表明:某些情况下P-Δ效应会显著增大下部结构的响应。更多还原

【Abstract】 For the dynamic response analysis of structures with isolators on the top of the columns,an iteration-free algorithm was proposed.The influences of P-Δ effects on the responses of the substructure were studied extensively.Because of the large storey drift,the second-order effects can not be neglected when the axis-forces are large.Bilinear hysteric model was adopted to model the behavior of isolators,the moments formed by axis-forces were replaced by equivalent horizontal force couples,and some special measures were fulfilled to transfer the moment of the isolation layer to the substructure.Consequently,geometric stiffness matrix was obtained and the iteration was avoided.The results show that P-Δ effects apparently enlarge the responses of the substructure in some cases.更多还原