地铁隧道群对沿线地震动的影响-土木工和;防灾减灾工程与防护工程专业论文.docxVIP

，飞 4 : 摘要 近年来随着城市地面交通情况愈发拥挤，城市地下铁道以其安全、快捷、舒 适的优势成为人们开始选择的全新交通模式。研究地铁隧道群对地震动的影响具 有革耍的理论意义和现实价值。 本文利用有限元分析程序 FLUSH，研究了线性均匀场地、非线性均匀场地、 线性层状场地和非线性层状场地四种场地中地铁隧道群对地震动的影响，给出了 时域中地表地震动反应。 首先通过建立宽度不同的…系列单隧洞模型，研究了进射边界到隧洞中心距 ‘;. 离的职值。然后对单隧洞场地下，混凝土衬砌存在与否对地震动的影响进行了研 究。研究表明:透射边界对计算精皮影响很小，距隧洞边缘 2 倍网格尺寸时即町 保证精度稳定。衬砌的存在对地表的地震反!卓有较大的影响。 ‘ f 均匀场地的研究。首先研究了三种地震波激胁下线性均匀场地和非线性均匀 场地自由场反应，接着研究了均匀场地隧道间距对地震动的影响。研究表明:非 线性均匀场地自由场加速度崎值要小于线性均匀场地加速度峰值;不同地震波激 励作用下，隧道群相互影响的距离不同;线性场地和非线性场地隧道群相互影响 的距离也不相同。 层状场地的研究。首先研究了三种地震波激励下线性层状场地和非线性居状 场地自由场反应。接着研究了层状场地隧道间距对地震动的影响。研究表明:层 状场地的地震动加速度峰值要大于相应的均匀场地加速度峰值，井且加速度峰值 对应频率向高频移动;均匀场地和层状场地隧道群相互影响的距离也不相闷。 关键词:地铁隧道群有限元散射地震动均匀场地居状场地非线性 4 4 . ABSTRACT 、， (f b ‘， - With the city in recent years become increasingly ∞ngested traffic conditions in the ground ，the city metro for its safe，阳剖，comfortable advantage as people began to select a new mode of transpo比 of subway tunnel on ground motion group of great theoretical and practical value. In this paper，finite element analysis program FLUSH，been done in four kinds of media including linear homogeneous site，layered linear site， nonlinear homogeneous site and layered nonlinear site. The time domain response of surface ground motion was given. First of all，through the establishment of a series of different width tunnel model，insurance the distance from the transmitting boundary to the center tunnel. Then the single tunnel site，the presence or absence of ∞ncrete lining of the ground motion was studied. 丁he results show that: transmi位.ing boundary has little e仔ect on the calculation accuracy，from the tunnel when the edge of two times the grid size can guarantee a∞uracyand s恼bility. The existence of the surface lining of the seismic response have greater impact. Uniform field research. First of all，the three kinds of ea叫lquake waves uniform site linear and nonlinear uniform free field response. Then on uniform field of the tunnel site e.忏ects on ground motion. Res