中文摘要：

采用有限单元法代替传统的综合折减系数法，对某导流隧洞的渗透水压力进行了计算分析．计算表明对于完整衬砌结构，当围岩渗透系数远大于衬砌渗透系数时（1000倍以上），隧洞对山体地下水位的影响甚小，外水压力折减系数可以达到0．87以上，当围岩渗透系数与衬砌渗透系数相当时（1～10倍），隧洞对山体地下水位有较大扰动，外水压力折减系数在0．3以下．同时计算表明衬砌施工冷缝张开时排水效果显著，能显著降低隧洞周边的渗透水压力，但造成局部渗透水压力梯度明显增大．

英文摘要：

External water pressure reduction factor is one of the main kinds of factors on diversion tunnel. FEM is adopted to substitute for classical reduction factor method in the diversion tunnel external water pressure analysis. The results show that the tunnel with integral lining has little influence on the groundwater level and the external water pressure reduction factor is more than 0.87 when the rock permeability coefficient is much larger than ones of lining. And tunnel has obvious influence on the groundwater level and external water pressure reduction factor is less than 0. 3 when the rock permeability coefficient is about from 1 to 10 times ones of the lining. The lining with construction cold joint has significant drained-effect on the tunnel and the external water pressure can be reduced substantially. But the local osmotic gradient increases markedly.