文档介绍：西安地铁南门车站基坑变形规律监测研究
西安地铁南门车站基坑变形规律监测研究
摘要:本文给出了西安市地铁二号线南门站深基坑围护和变形监测方案,对基坑的桩身水平位移、钢支撑轴力、围护桩桩顶沉降和基坑周围地表沉降变化规律进行了现场监测研究。结果表明:桩顶水平位移反映围护结构的顶部变形规律情况,能直接反映围护结构的变形特征,是评价围护结构安全状况的重要指标;在有钢支撑作用的情况下,围护桩变形最大的部位位于距桩顶2/3基坑开挖深度处;钢支撑轴力随开挖深度增加而增加。基坑周围地表沉降和桩顶沉降在施工初期累计沉降值较小且基本稳定,开挖中后期由于受到地质条件、覆土厚度、施工方法等多种因素的相互影响,使得变化值及波动较大。
关键词:地铁;深基坑;变形规律;现场监测
Abstract: The deep foundation pit retaining and deformation monitoring plan of the south gate station of xi 'an metro line 2 are introduced in this paper, the foundation pit horizontal displacement of pile, steel support axial forces, retaining pile top settlement and the ground settlement around the change rule for the study of field monitoring. Results show that the displacement of pile top level reflect the top of the retaining structure deformation law, can directly reflect the characteristics of deformation of retaining structure, is important for retaining structure security evaluation indicator; In a case with steel support, retaining pile deformation is the biggest part of pile top two-thirds of pit excavation depth; Steel support axial force increases with the increase of excavation depth. The ground settlement around the foundation pit and the pile top settlement in the early construction accumulated subsidence value small and stable, excavation later due to geological conditions, thickness of covering soil, construction method and so on m