薄钢板剪力墙地震力折减系数和位移放大系数分析

Seismic Force Modification Factor and Inelastic Displacement Amplification Factor Analysis of Thin Steel Plate Shear Wall

基于薄钢板剪力墙的等效拉杆理论,利用SAP2000有限元分析软件,通过10层3跨结构倒三角型和均匀分布两种基本加载模式的底部剪力V-顶点位移Δ曲线和多条地震波增量动力分析法得到的平均V-Δ曲线的差值建立了函数关系,获取了相关的计算系数,进而推算出了7跨相同层数的结构在地震作用下的抗震性能。对所设计的抗弯钢框架-薄钢板剪力墙结构体系的抗震性能进行了评估,通过Matlab语言编写的能力谱法程序计算出了结构在小震和中震下前三阶振型的需求谱、能力谱和性能点。利用改进的能力谱法计算出了10层7跨抗弯钢框架-薄钢板剪力墙结构中震下的地震力折减系数R、超强系数R_Ω和延性折减系数R_μ分别为2.81、2.58和1.09;大震下的位移放大系数Cd为4.12。

Based on the theory of equivalent tensile rods,the function equation is established to acquire the relevant coefficients of 10-storey 3-span structure according to the diffidence between the base shear V- roof displacement Δ curve obtained from two basic loading patterns of inverted triangle and uniform distribution and the average V-Δ curve derived from IDA under multiple seismic waves through the finite element software SPA2000,and then the seismic behavior of 7-span structure with the same number of storey under horizontal seismic action is deduced. The seismic performance of designed steel frame-thin steel plate shear wall is evaluated and the demand spectrum,capacity spectrum and performance point of structure at the first three order vibration modes under small earthquake and middle earthquake are further calculated by the own capacity spectrum method program written by Matlab language. The seismic force modification factor R,over-strength factor R_Ω and ductility reduction factor R_μ calculated by using the improved capacity spectrum method for 10-storey 7-span steel frame-thin steel plate shear wall structure under middle earthquake are 2. 81,2. 58 and 1. 09,respectively. The inelastic displacement amplification factor C_d under severe earthquake is 4. 12.