关于地下结构云图法地震易损性分析中输入地震动最优数量的探讨  

Discussion on the optimum number of input ground motions in seismic fragility analysis of underground structures by cloud method

作　　者：庄海洋 杨靖[2] 刘园园 唐柏赞 ZHUANG Haiyang;YANG Jing;LIU Yuanyuan;TANG Baizan(School of Civil Engineering and Architechue,East China Jiaotong University,Nanchang 330013,China;Institute of Geotechnical Engineering,Nanjing Tech University,Nanjing 210009,China)

机构地区：[1]华东交通大学土木建筑学院,江西南昌330013 [2]南京工业大学岩土工程研究所,江苏南京210009

出　　处：《振动工程学报》2025年第3期587-594,共8页Journal of Vibration Engineering

基　　金：国家自然科学基金资助项目(51978333);南京工业大学优秀博士学位论文培育计划资助项目;江西省主要学科学术和技术带头人培养计划项目(20204BCJL23032)。

摘　　要：本文基于地震易损性分析方法,设计样本随机抽取程序,探究了云图法中不同输入地震动数量对于地下结构地震易损性曲线的影响。以浅埋两层三跨地铁车站结构为研究对象,建立土-地下结构非线性动力相互作用有限元模型,选取350条天然地震动记录作为输入,计算获得了350个工况下该地下结构的地震响应。选取层间位移角(IDR)作为结构地震损伤参数,地震动峰值地表加速度(PGA)作为地震动强度参数,构建了该地下结构的地震易损性曲线。结果表明,当输入地震动数量小于190条时,输入数量对地下结构各抗震性能等级的PGA阈值影响较大;当输入地震动数量大于190条时,地下结构的轻微破坏及中度破坏的地震易损性曲线不受输入数量的影响;当输入地震动数量大于280条时,严重破坏及倒塌的曲线受输入数量的影响也基本可忽略。当常见的两层三跨地下结构处于强震(PGA<0.3g)威胁概率较低的区域时,本文推荐选用190条天然地震动作为输入,当处于强震威胁概率较高的区域时,推荐输入280条天然地震动。Based on the seismic fragility method,this paper designed a random sampling procedure to investigate the effect of different amounts of input ground motions on the seismic fragility curves of underground structures in the cloud method.Taking a shallow-buried subway station with two-story and three-span as the research object,a non-linear dynamic interaction finite element model of the soil-underground structure was established,and 350 natural ground motions were selected as inputs to calculate the seismic response.The seismic fragility curves were constructed based on PGA-IDR finally.The results show that the amount of input ground motions has a greater effect on the PGA thresholds for each performance level of underground structures when the amount is less than 190.When the amount is greater than 190,the seismic fragility curves for minor and moderate damage to underground structures are not affected by the amount;when the amount is greater than 280,the curves for extensive damage and collapse are negligibly affected by the amount.When the underground structure is in an area with a low probability of strong seismic threat,this paper recommends 190 natural ground motions as inputs,otherwise,it should be 280.

关 键 词：地铁车站结构 输入地震动 地震易损性 抗震性能 

分 类 号：TU921[建筑科学—建筑设计及理论] TU311.3