组合框架-核心筒结构地震反应初步规律研究

Preliminary study on seismic response of composite frame-core wall structures

对外部由钢管混凝土柱和钢-混凝土组合梁组成的组合框架,内部为RC核心筒的305个组合框架-核心筒结构进行了弹性地震反应的参数分析,初步探讨了外框架梁、柱截面、核心筒厚度及楼层数变化对结构变形性能和外框架剪力的影响规律.研究了结构刚度特征值对最大层间位移角位置和外框架楼层最大剪力位置的影响规律.结果表明:对于该结构模型,单独增大柱截面对减小结构位移反应效果不明显,同时增大梁、柱尺寸或核心筒厚度均可有效降低结构的弹性位移反应.随着核心筒厚度的增加,外框架承担的剪力和剪力分担率减小,在结构中上部减小比率较大.结构最大层间变形和框架剪力起控制作用的是中上部楼层.

A parametric analysis of elastic seismic response of 305 composite frame-RC core wall structures with the inner part of RC core walls and the outer part of concrete-filled square steel tubular columns and steel-concrete composite beams was carried out.The effects of dimensions of beams and columns,thickness of RC core walls and number of stories on the deformation and mechanical behaviors of the structures were preliminarily investigated.The influences of the characteristic values of the structural stiffness on the locations of the maximum storey drift angle and the outer frame shear force are studied.The conclusions are drawn that for the proposed structural model,only enlarging the dimension of the columns has no obvious effects on the decrease of the structural displacement response.While enlarging the dimensions of the columns and the beams simultaneously or the thickness of the core walls can effectively reduce the elastic seismic displacement response.With the increase of the thickness of the core walls,shear force and force distribution rates of the outer composite frame decrease and the decrease ratio is larger especially in the middle and upper parts of the structures.Accordingly,the control storey of the maximum storey deformation and the outer frame shear force is in the middle and upper parts of the structures.