软土盾构隧道非达西渗流引起的沉降解析研究  

Analytical Solution for Non-Darcy Flow Induced Settlement of Shield Tunnel in Soft Soil

作　　者：陈恺[1,2] Chen Kai(Beijing MTR Construction Administration Corporation,Beijing 100068,P.R.China;Beijing Key Laboratory of Fully Automatic Operation and Safety Monitoring for Urban Rail Transit,Beijing 100068,P.R.China)

机构地区：[1]北京市轨道交通建设管理有限公司,北京100068 [2]城市轨道交通全自动运行系统与安全监控北京市重点实验室,北京100068

出　　处：《地下空间与工程学报》2023年第5期1454-1461,1488,共9页Chinese Journal of Underground Space and Engineering

摘　　要：在饱和软土地层中,渗漏水是盾构隧道主要病害之一,亦是引起地表及隧道长期沉降的主要原因。基于镜像法,假定土体渗流服从Slepicka指数渗流模式,衬砌渗流服从达西线性渗流模式,推导了非达西渗流条件下浅埋圆形盾构隧道周围土体孔隙水压力分布解析解,在此基础上,进一步取得了隧道沉降解析表达式。结合算例,验证了所提出的解析解的正确性,并进一步分析了非达西渗流对隧道周围土体孔压与隧道上方地表沉降的影响。结果表明:非达西渗流指数m对隧道周围土体的孔压分布与地表沉降均具有显著的影响,m值越大,隧道周围土体的孔压越小,地表沉降越大;分析饱和软土盾构隧道渗流问题必须考虑非达西渗流的影响。研究可为类似工程的设计与施工提供参考。Leakage is one of the main diseases of subway shield tunnel in the saturated soft soil,and it is also the main cause of the long-term settlement of the stratum and tunnel.Seepage in the soil was assumed to follow the Slepicka exponential seepage model,while the seepage in the lining was assumed to follow the Darcy linear seepage model,and the analytical solution of the pore-pressure distribution of the soil around the shallow tunnel under the condition of non-Darcy seepage was derived.On this basis,the analytical solution of the tunnel settlement was further obtained.The correctness of the proposed analytical solutions were verified by case analysis,and the influence of non-Darcy seepage on the pore-pressure of soil around the tunnel and the surface settlement above the tunnel was further analyzed.The results show that the non-Darcy seepage index m has a significant impact on the pore-pressure distribution and surface settlement of the soil around the tunnel.With increasing the value of m,the pore-pressure of the soil around the tunnel is gradually reduced,and the surface settlement is gradually increased.The influence of non-Darcy seepage must be considered in analyzing the seepage of shield tunnel in saturated soft soil.This paper can provide some reference for the design and construction of similar projects.

关 键 词：饱和软土 盾构隧道 非达西渗流 孔压 沉降 

分 类 号：TU921[建筑科学—建筑设计及理论]