山岭隧道地下水渗流及加固参数的解析研究

Analytical Research on Groundwater Seepage and Reinforcement Parameters of Mountain Tunnels

为研究山岭隧道渗流压力、渗流量以及加固参数对渗流的影响,假定圆形隧道周围存在各向同性的径向稳定渗流场,推导了地下水渗透压力分布规律及渗流量公式.实例分析表明,渗透压力的分布具有非线性特征,在排水情况下设置围岩加固圈和初期支护可明显减少作用在衬砌上的渗透压力及地下水排放量.运用文中公式计算的毛洞渗流量比较接近相关资料提供的实际涌水量,说明文中方法对预测类似隧道涌水量具有一定的参考价值.另外,由加固参数与水压力及渗流量的相关性分析可知,随着加固圈渗透系数的减小及厚度的增加,二次衬砌上的渗流压力和渗流量一开始急剧减小,当加固参数达到一定界限值时,地下水渗流压力及渗流量基本保持不变.

In order to investigate the seepage pressure and discharge of mountain tunnels and reveal the effect of grouting reinforcement parameters on groundwater seepage, the distribution law of seepage pressure and the formu- las of seepage discharge are deduced based on the assumption that there exists a radial stable and isotropic seepage around a circular tunnel. Then, a case study is performed. It is found that the distribution of the seepage pressure is nonlinear and that the reinforcement rim and the primary support greatly reduce the seepage pressure loading on the lining and the groundwater discharge in drainage conditions. The seepage discharge of the unlined tunnel calcu- lated by the proposed formulas is close to the actual monitoring data, which means that the proposed method is fea- sible in evaluating the water inflow of similar tunnels. Moreover, according to the correlation between the reinforce- ment parameters and the seepage pressure as well as the seepage discharge, it can be deduced that, with the de- crease in the permeability coefficient and with the increase in the reinforcement rim thickness, both the seepage pressure on the secondary lining and the seepage discharge decrease sharply at first, and then remain unchanged when the reinforcement parameters increase to certain values.