Based on conformal mapping of the complex variable function, the semi-infinite plane of a tunnel was transformed into a concentric ring region. With the soil around the tunnel regarded as a homogeneous, continuous, isotropic, saturated medium, the boundary collocation method was applied to control the local leakage of shield tun?nels. The analytic method and numerical method were combined to solve the basic differential equation of the two-dimensional seepage of saturated soil masses under steady seepage, and a semi-numerical and semi-analytical solu?tion of pore water pressure variations due to local water leakage of shield tunnels is obtained. The effects of the wa?ter leakage range, location, and total water head difference between the ground surface and the tunnel leakage boundary on the pore water pressure of the soil mass around the tunnel are discussed through this calculation meth?od. The results show that there are great changes to the pore water pressure under a one time central buried depth of a tunnel in the horizontal direction when lateral water leakage occurs, and the larger the leakage range, the more sig?nificant the decay rate of the pore water pressure;the larger the total water head difference between the ground sur?face and tunnel leakage boundary, the more obvious the influence is on the pore water pressure of the soil mass, and it is proportional to the total water head difference and volume of the pore water pressure reduction;and the lateral leakage volume of tunnels increases with an increase of the total water head difference, being characterized by a lin?ear relationship.%文章基于复变函数的保角变换方法将含有隧道的半无限平面映射为同心圆环计算域,将隧道周围土体视为均质连续各向同性的饱和介质,通过边界配点法控制盾构隧道局部渗漏水的边界条件,并将解析法与数值法相结合求解了稳定渗流时饱和土体二维渗流的基本微分方程,得到了盾构隧道局部渗漏水引起周围土体孔隙水压力变化的半数值半解析解.结合工程算例,应用该计算方法探讨了隧道渗漏水范围、渗漏水位置、地表与隧道渗漏水边界处总水头差等因素对隧道周围土体孔隙水压力的影响.研究结果表明:盾构隧道发生侧向渗漏水时,周围土体孔隙水压力在水平向1倍隧道中心埋深的范围内变化较大,且渗漏水范围越大,其衰减速度越显著;隧道渗漏水引起的地表与隧道渗漏水边界处总水头差越大,其对土体孔隙水压力的影响越显著,且孔隙水压力的减小量与总水头差呈等比例变化;隧道侧向渗流量随地表与隧道渗漏水边界处总水头差的增大而增大,且两者呈线性关系.
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