与桥梁抗震规范设计反应谱一致的地震动合成  

Seismic synthesis consistent with the design response spectrum of code for seismic design of bridges

作　　者：范立朋 姜云木 Fan Li-peng;Jiang Yun-mu(Guangdong Shengxiang Trffie Engineering Testing Co.Ltd,Guangzhou 511400,China;Guangdong Communication Planning&Design lnstitute Group Co.Ltd,Guangzhou 511400;School of Civil Engineering and Architecture,Wuhan Institute of Technology,Wuhan 430074,China)

机构地区：[1]广东盛翔交通工程检测有限公司,广东广州511400 [2]广东省交通规划设计研究院集团股份有限公司,广东广州511400 [3]武汉工程大学土木工程与建筑学院,湖北武汉430074

出　　处：《工程抗震与加固改造》2024年第2期68-76,共9页Earthquake Resistant Engineering and Retrofitting

基　　金：国家自然科学基金(51778343)。

摘　　要：工程上在对结构进行动力响应分析时,大多是在实测强震数据库中筛选出与规范设计反应谱相一致的实测强震记录作为地震动输入依据,然而,实测强震记录数量有限,需要系统地处理才可投入工程应用,且在对大型工程结构进行动力反应分析时无法体现地震动的空间变异性,因此,本文以《公路桥梁抗震设计规范》(JTG/T 2231-01-2020)中的设计反应谱为例,详细梳理了地震动向量过程的本征正交分解方法(POD)和复相干函数模型,并将反应谱转化功率谱法和调幅功率谱迭代法相结合,基于降维模拟方法,在概率层面上高效地生成了与设计反应谱相一致且具有空间变异性和非平稳性的人工地震动向量过程。数值算例表明,根据目标反应谱转化为调幅功率谱后,再根据功率谱迭代法迭代一次生成的地震动样本与目标反应谱对应良好,同时,降维方法生成的地震动样本具有显著的非平稳性和空间变异性,且统计特征与目标值对应良好。可以认为,本文为桥梁结构在地震作用下的地震激励输入提供了新的途径。In the dynamic response analysis of structures in engineering,most of the measured strong earthquake records consistent with the design response spectrum in the code are selected from the measured strong earthquake database as the ground motion input basis.However,the number of measured strong earthquake records is limited and can be put into engineering application only after systematic processing,and the spatial variability of ground motion cannot be reflected in the dynamic response analysis of large engineering structures.Therefore,taking the design response spectrum in the code for seismic design of highway bridges(JTG/T 2231-01-2020)as an example,this paper details the proper orthogonal decomposition method(POD)and complex coherence function model of ground motion vector process.Based on the dimension reduction simulation method(DR),the artificial ground motion vector process which is consistent with the design response spectrum and has spatial variability and non-stationarity is efficiently generated at the probability level.Numerical examples show that after the target response spectrum is transformed into amplitude modulated power spectrum,the ground motion process generated by the power spectrum iteration method correspond well to the target response spectrum.At the same time,the ground motion process generated by the dimension reduction method have significant non-stationarity and spatial variability,and the statistical characteristics correspond well to the target value.It can be considered that this paper provides a new way for the seismic excitation input of bridge structure under earthquake.

关 键 词：地震动向量过程 调幅功率谱模型 人工地震动合成 桥梁抗震设计规范 功率谱迭代 

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]