超高层混合结构增量动力分析的地震动强度指标

Seismic intensity index for incrementel dynamic analysis of super high-rise hybrid structures

在进行超高层结构设计时,地震动强度指标是指导结构抗震设计的重要依据,对结构的安全至关重要,但目前并没有统一的结论,因此,对超高层结构进行地震动强度指标的研究具有重要意义。在综述建筑结构增量动力分析地震动强度指标有效性研究现状的基础上,提出适用于超高层建筑结构增量动力分析的地震动强度指标Sa%,地震动强度指标Sa%是考虑结构前a%振型质量参与系数的自振周期所对应谱加速度的几何平均值;为了验证地震动强度指标Sa%的有效性,以实际超高层为例,使用PERFORM-3D弹塑性分析软件建立非线性模型并进行增量动力分析,根据各种地震动强度指标的θmax和Vmax结果进行离散性分析,发现地震动强度指标Sa%用于超高层结构增量动力分析时能有效减少θmax和Vmax数据的离散性,从而提高计算数据的有效性,为实际超高层结构的应用提供参考。

In design of super high-rise structure,the ground motion intensity index guides the seismic design of the structure and is very important for safety of the structure,but there is no unified conclusion on the ground motion intensity index of super high-rise mixed structure.Therefore,it is of great significance to study the ground motion intensity index of the super high-rise structure.Based on the review of the current research status of the effectiveness of seismic intensity index in the incremental dynamic analysis of building structures,this article proposes a seismic intensity index a%,which is suitable for the incremental dynamic analysis of super high-rise building structure.The ground motion intensity index Sa%is the geometric average of the spectral acceleration corresponding to the natural vibration period of a%mode mass participation coefficient before considering the translational direction of the structure.In order to verify the effectiveness of the seismic intensity index Sa%,PERFORM-3D elastoplastic analysis software was used to establish a nonlinear model of an actual super high-rise building and perform incremental dynamic analysis.Based on the discrete analysis ofθmax and Vmax results of various ground motion intensity indexes,it is concluded that Sa%of ground motion intensity index proposed in this paper can effectively reduce the discreteness ofθmax and Vmax when applied to incremental dynamic analysis of super-high-rise structures,which improves the validity of calculated data and provides reference for the application of actual super high-rise structures.