基坑开挖引起邻近既有隧道变形的拟合分析及预测  

Fitting analysis and prediction for deformation of existing tunnels adjacent to the excavation

作　　者：孙佳羽 杜一鸣[1,2] 郑刚[1,2] 杨新煜 SUN Jia-yu;DU Yi-ming;ZHENG Gang;YANG Xin-yu(Department of Civil Engineering, Tianjin University, Tianjin 300072, China;Key Laboratory of Coast Civil Structures and Safety of Ministry of Education, Tianjin University, Tianjin 300072, China)

机构地区：[1]天津大学土木工程系,天津300072 [2]天津大学滨海土木工程结构与安全教育部重点实验室,天津300072

出　　处：《中国港湾建设》2017年第3期10-17,共8页China Harbour Engineering

摘　　要：邻近既有隧道的基坑开挖,由于卸荷作用会使隧道产生变形,超过安全控制值将会对隧道的正常使用和安全运营产生影响,因此对隧道的变形控制至关重要。文中以天津某邻近既有隧道的深大基坑工程实例为依托,验证了考虑土体小应变刚度特性的有限元方法的准确性,并通过大量的二维计算模型分析邻近隧道最大水平位移与基坑开挖深度、隧道距基坑的相对位置、围护结构最大水平位移间的变形规律,提出预测邻近隧道最大水平位移的计算表达式。通过文中提出的方法进行工程预测更加省时简便,且与实测数据对比表明该方法可以较好地预测天津等软土地区基坑开挖引起的邻近隧道最大水平位移。When excavation is close to existing tunnel,it would lead to tunnel deformation as a result of unloading.Deformation which exceeds the safety control values would have important effect on the normal usage and safe operation oftunnel.So it is important to control the deformation of tunnel.Based on a construction project of deep foundation pit of anadjacent existing tunnel in Tianjin,we verified the accuracy of the finite element method which considering the nonlinear andsmall strain character of soil.Parametric study was performed with2D model to obtain the relationship between the maximumhorizontal displacement of tunnel and the excavation depth,the relative location of tunnel as well as the maximum horizontaldeformation of retaining structures.Finally a simplified calculation formula was proposed to predict the maximum horizontaldisplacement of the existing tunnel.It would be more time-saving and convenient.The calculated results were compared withthe engineering projects.It showed the simplified calculation formula could accurately predict the maximum horizontaldisplacement of tunnel caused by excavation in Tianjin and other coastal soft soil areas.

关 键 词：基坑开挖 既有隧道 数值分析 拟合分析 

分 类 号：U655.54[交通运输工程—港口、海岸及近海工程]