考虑地震环境及其目标谱不确定性的实际地震动选择和调整方法研究

项目名称： 考虑地震环境及其目标谱不确定性的实际地震动选择和调整方法研究

项目编号： No.51508527

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 建筑环境与结构工程学科

项目作者： 陈波

作者单位： 中国地震局地球物理研究所

项目金额： 20万元

中文摘要： 合理确定地震动输入是保证结构性能评估有效实施的必要条件，目前的地震动选取方法缺乏对地震环境及其目标谱不确定性特征的充分考虑，不利于实现对结构地震反应的无偏估计。本项目将基于实际地震动记录，着眼于有效获取特定地震环境下结构地震反应的概率分布特征，研究可考虑目标谱不确定性的地震动选择和调整方法。在地震动选择方面，通过定量分析震级、距离偏差对结构非线性地震反应的影响，研究匹配结构所处地震环境所容许的偏差范围，给出地震动选择的判断准则；在地震动调整方面，借助多元随机模拟方法，考虑地震动谱形的影响，发展可同时匹配目标谱均值、方差等统计特征的地震动优化调整方法，使调整后的记录能够充分反映地震危险性水平的不确定性特征。建立强震记录数据库搜索引擎，实现地震动记录选择和调整的高效程序化处理。鉴于地震动输入对于结构地震反应估计的重要影响，本研究对特定地震环境下基于概率的结构性能评估具有重要理论意义和应用价值。

中文关键词： 地震动；地震动选择；地震动调整；地震环境；不确定性

英文摘要： The issue of determining ground motion input reasonably is the necessary condition for performing structural seismic assessment. However, the majority popular approaches of selecting records at present do not take full account of the inherent variance of seismic environment and its target spectrum; it is not conducive to obtain un-biased structural response. With an aim to capture the probability distribution characteristics of structural seismic response, an optimized real ground motion records selection and modification method (GMSM) considering the uncertainty of target spectrum will be developed in this study. For ground motion selection issue, we will quantitatively study the influence of such factors including magnitude and distance on the structural nonlinear seismic response, thus stating key elements and allowable error for selecting records in term of the target seismic environment where the structure is located. For ground motion modification issue, by means of multivariate Monte Carlo stochastic simulation method and the spectral shape parameter will be introduced to optimize the scaling approach which can match the mean and variance of target spectrum, so the uncertainty characteristics of seismic hazard level could be adequately represented in the modified ground motion input. Furthermore, strong ground motion database and search engines will be established to determine records programmatically and efficiently. Given that ground motion input plays an important role in predicting structural nonlinear response, this project can lay the important theoretical significance and applied value for evaluation of probability-based seismic performance of buildings under scenario earthquakes.

英文关键词： ground motion;ground motion selection;ground motion scaling;seismic environment; uncertainty