半刚性框架-屈曲约束钢板剪力墙结构弹塑性层剪力分布研究

Elasto-plastic story shear distribution of semi-rigid frame with buckling-restrained steel plate shear walls

为研究弹塑性状态下半刚性框架-屈曲约束钢板剪力墙结构(BR-SPSW)的层剪力分布,设计了具有理想屈服模式的5层、10层、15层和20层的BR-SPSW结构等效拉杆简化模型。综合考虑结构层数、构件截面、近场地震速度脉冲效应及远场地震加速度循环累积效应对结构的影响,采用弹塑性时程分析方法获得了BR-SPSW结构在两类地震作用下的层剪力分布平均值,提出了BR-SPSW结构弹塑性状态的层剪力分布模式,并基于已有层剪力分布模式及GB 50011-2010《建筑抗震设计规范》的底部剪力法提出的层剪力分布模式进行对比。结果表明,近场地震波的速度脉冲效应和远场地震波的加速度循环效应对半刚性框架-屈曲约束钢板墙的层剪力分布影响较大,层剪力分布应综合考虑二者的影响。建议的层剪力分布模式在计算精度上优于其他层剪力分布模式,可为屈曲约束钢板墙结构基于性能的设计方法提供参考。

In order to investigate the elasto-plastic story shear distribution of semi-rigid steel frame with bucklingrestrained steel plate shear wall( BR-SPSW),five BR-SPSWs with buckling constraint equivalent strip simplified models of 5,10,15 and 20 stories with ideal yield mechanism were designed. Meanwhile,the effects of story number,cross-section of the members,velocity impulse of near-field ground motions and acceleration cumulative effect of farfield ground motions,were considered. The average story shears of the BR-SPSW structures under the two types of earthquake records were obtained through a nonlinear time-history analysis. An analytical model for the elasto-plastic story shear distribution of BR-SPSWs was proposed,and the prediction was compared with the story shear distribution pattern derived from the existing base shear method stipulated in GB 50011-2010 ‘Code for seismic design of buildings’. The results indicate that the near-field ground motions with velocity pulse and far-field ground motions with acceleration cumulative effects have obviously different effects on the story shear distribution of the BR-SPSWs,and the influence of the two factors should be comprehensive considered. The story shear distribution obtained in this paper is found to have improved accuracy than the other ones,and provides a reference for energy design method of BRSPSW.