多点多维全非平稳地震动场的降维模拟  

Dimension-reduction simulation for multi-support and multi-component spatially correlated fully non-stationary ground motion fields

作　　者：刘子心 刘章军 LIU Zi-xin;LIU Zhang-jun(School of Civil Engineering, Institute of Disaster Prevention,Langfang 065201,China;School of Civil Engineering and Architecture,Wuhan Institute of Technology,Wuhan 430074,China)

机构地区：[1]防灾科技学院土木工程学院,河北廊坊065201 [2]武汉工程大学土木工程与建筑学院,湖北武汉430074

出　　处：《振动工程学报》2020年第5期1002-1012,共12页Journal of Vibration Engineering

基　　金：国家自然科学基金资助项目(51978543,51778343,51278282)。

摘　　要：首先,在多点一维全非平稳地震动场的随机模型基础上,导出了多点多维全非平稳地震动随机场基于相干函数矩阵的谱分解统一表达式。同时,通过引入随机函数的约束形式,实现了多点多维地震动随机场的降维模拟。其次,根据多维地震动三分量强度调制函数中参数相关性的回归结果,给出了Ⅰ0类场地的三维地震动四段强度调制函数的参数取值。最后,以三维地震动的松岛丰模型为基础,采用四段强度调制函数、Clough-Penzien时变功率谱以及复合相干函数模型,生成了空间相关多点多维全非平稳地震动的代表性样本,数值算例验证了所提方法的有效性。由于该方法生成代表性样本集合的概率信息完备,进而可与概率密度演化方法相结合,以实现随机地震作用下大型复杂空间结构的精细化动力反应分析以及抗震可靠性评价。In this study,firstly,based on the stochastic model of multi-support and one-component fully non-stationary ground motion fields,the unified spectral decomposition representation of the multi-support and multi-component fully non-stationary ground motion stochastic fields on the basis of the coherence function matrix is derived.Furthermore,by introducing the constraint form of random function,the dimension-reduction simulation of the multi-support and multi-component stochastic ground motion fields is realized.Then,according to the regression results of the correlation involved in the intensity envelope function parameters of the multi-component ground motions,the four-segment intensity envelope function parameter values of the three-component ground motions for soil siteⅠ0 are suggested.Finally,based on the Matsushima′s model of three-dimensional ground motions,through adopting the four-segment intensity modulation function,the Clough-Penzien time-varying power spectrum and the composite coherence function model,the representative samples of the spatially correlated multi-support and multi-component fully non-stationary ground motions are generated.Numerical examples verify the effectiveness of the proposed method.Due to the probability information of the generated representative samples set by this method is complete,it can thus be combined with the probability density evolution method to achieve the refined dynamic response analysis and seismic reliability evaluation of large and complex spatial structures subjected to earthquake disasters.

关 键 词：多点多维地震动 空间相关 全非平稳过程 谱分解 降维模拟 

分 类 号：P315.9[天文地球—地震学] TU311.3[天文地球—固体地球物理学]