隧道洞口段结构地震响应分析  

Analysis of Anti-seismic Fortified Length in Tunnel Portal and Outlet

作　　者：苏惠[1] 贾良[1] 严松宏[2] 张巧慧[1] 

机构地区：[1]陕西铁路工程职业技术学院铁道工程系,陕西渭南714000 [2]兰州交通大学土木工程学院,甘肃兰州730070

出　　处：《水利与建筑工程学报》2010年第2期156-158,共3页Journal of Water Resources and Architectural Engineering

摘　　要：隧道的进出口大多是风化的松散堆积体,是抗震设防的薄弱环节。运用Newmark隐式时间积分有限元法,采用粘-弹性人工边界,对在地震荷载作用下围岩材料的渐变对隧道洞口段抗震性能进行分析。得到了3种工况下沿隧道轴线方向衬砌最大应力、位移以及加速度变化曲线,及不同工况下洞口段隧道结构的抗震设防长度。洞口段设防长度与洞口段围岩性质有关,洞口段围岩由软弱向坚硬渐变长度越长,洞口段衬砌应力就越大,洞口段设防长度就越长。The tunnel portal and outlet are the weak links for anti-seismic fortifying as they are weathered accumulation bodies. Based on Newmarks implicit integration FEM and under the earthquake load, the inffluence on seismic responses in tunnel portal and outlet because of the changed surrounding rock is analyzed by using visco-elastic artificial boundary. The maximum stress, displacement and accelaration curve of lining along the axis direction of the tunnel under different work conditions are obtained, and the anti-seismic fortified lengths of tunnel structures are determined under different work conditions, providing the basis for selection of the anti-seismic fortified lengths of other similar tunnels.

关 键 词：隧道洞口段 抗震设防长度 有限元法 粘-弹性边界 

分 类 号：U452.28[建筑科学—桥梁与隧道工程]