富水区深埋隧洞不同渗控措施下的外水压力解析计算方法研究

Research on Analytical Calculation Method of External Water Pressure under Different Seepage Control Measures in Deeply Buried Tunnels in Water-Rich Areas

为了探究富水区深埋隧洞高外水压力作用规律,研究不同支护形式对于外水压力作用规律带来的影响,本文基于等效连续介质渗流模型和无限含水层井流理论,推导了采用复合支护方式下隧洞的外水压力解析计算公式,并通过解析退化以验证公式的正确性.在此基础上,给出复合支护方式的外水压力折减系数解析计算公式.结合外水压力折减系数解析计算公式,对地下水作用水头、衬砌厚度及渗透性、固结灌浆圈厚度及渗透性等因素对外水压力作用规律的影响进行了探究,绘制关系曲线对外水压力的作用规律进行了总结.为保障富水区深埋隧洞工程施工及后期运营安全和富水区水工隧洞工程设计提供了分析手段和参考支持.

Ensuring the safety of tunnel linings deeply encased below substantial external water pressure stands as a significant challenge in the hydraulic tunnel design within water-abundant regions.The adoption of effective seepage control measures emerges as the linchpin for safeguarding both the construction and subsequent operational phases of the tunnel.In this paper,based on the equivalent continuous medium seepage model and the infinite aquifer well flow theory,the theoretical formulae for the external water pressure in tunnels with different support methods are derived and analytically degraded to verify the correctness of the formulae.Then,the theoretical formulas for the reduction coefficients of external water pressure are given for three types of support methods.Finally,the sensitivity analyses of the parameters affecting the reduction coefficients of external water pressure,such as the head of groundwater,the thickness and permeability of lining,and the thickness and permeability of solid grouting ring,are carried out,and the relationship curves are plotted.