水工隧洞渗流场解析求解方法比较研究  

Comparative study on analytical methods of seepage field of hydraulic tunnels

作　　者：陆进彬 李少龙[2] 崔皓东[2] 宋萌 龙杰 LU Jinbin;LI Shaolong;CUI Haodong;SONG Meng;LONG Jie(Yunnan Dianzhong Water Diversion Engineering Co.,Ltd.,Kunming 650000,China;Key Laboratory of Geotechnical Mechanics and Engineering of the Ministry of Water Resources,Changjiang River Scientific Research Institute,Wuhan 430010,China)

机构地区：[1]云南省滇中引水工程有限公司,云南昆明650000 [2]长江科学院水利部岩土力学与工程重点实验室,湖北武汉430010

出　　处：《人民长江》2024年第10期205-211,共7页Yangtze River

基　　金：云南省重大科技专项计划项目(202102AF080001)。

摘　　要：隧洞渗流量和衬砌外水压力是水工隧洞防排水设计和衬砌设计的重要参数,选取合理的渗流场计算方法对于计算结果的准确性至关重要。采用三种解析方法即竖井法、镜像法和保角变换法在一致的简化条件和坐标系下求解考虑围岩-灌浆圈-衬砌复合系统的富水地层水工隧洞渗流场,结合松林隧洞讨论了地下水作用水头、灌浆圈渗透性及厚度、衬砌渗透性等因素对隧洞渗流量和衬砌外水压力的影响,并通过与数值解比较分析了三种解析方法的差异。研究结果表明:竖井法与镜像法、保角变换法的差异主要是源于对围岩渗流场求解机理的不同,解析解对毛洞渗流量的预测结果大于数值解,主要原因之一是解析解没有考虑地下水位下降的影响;对于围岩-灌浆圈-衬砌复合系统的隧洞渗流量和衬砌外水压力,三种解析解与数值解的相对误差均小于10%;增加灌浆圈厚度或减小灌浆圈渗透性可有效降低隧洞渗流量及衬砌外水压力。研究成果可为富水地层水工隧洞渗流场预测分析提供参考。Seepage discharge volume of tunnel and external water pressure on lining are important parameters for waterproof and drainage design of hydraulic tunnels and linings.Choosing a reasonable calculation method is crucial for the accuracy of the calculation results.Three analytical methods,namely,vertical well method,image method and conformal mapping method,were used to solve seepage field of a hydraulic tunnel considering the complex system of surrounding rock,grouting circle and lining under the same simplified conditions and coordinate system.The effects of factors such as groundwater head,grouting circle permeability and thickness,and lining permeability on the tunnel seepage discharge and external water pressure on the lining were discussed aiming at Songlin tunnel.The differences between the three analytical methods were compared with numerical solutions.The results indicate that the difference results between the vertical well method,image method and conformal mapping method come from different calculation mechanism.The seepage discharge of unlined tunnel given by analytical solution is greater than that of the numerical solution,because the analytical solution does not consider the effect of groundwater level falling.For the tunnel seepage discharge and external water pressure of the surrounding rock-grouting circle-lining composite system,the relative errors between the three analytical and numerical solutions are all less than 10%.Increasing the thickness of the grouting circle or decreasing the permeability of the grouting circle can effectively reduce the seepage discharge of the tunnel and the external water pressure on linings.The research results can provide reference for predicting and analyzing the seepage field of hydraulic tunnels in water-rich formation.

关 键 词：水工隧洞 外水压力 渗流量 解析解 灌浆圈 竖井法 镜像法 保角变换法 

分 类 号：TV672[水利工程—水利水电工程]