燕山水库坝基防渗墙优化设计

Optimized design of anti-seepage wall of Yanshan reservoir’s dam foundation

因现场资料不足或分析手段落后等原因,当前进行水库坝基防渗墙设计,往往存在过于保守的倾向。以河南省燕山水库为例,基于优化设计的思路,采用目前较为成熟的二维有限单元法,对不同防渗条件下的坝基渗流场分别进行了模拟,并将计算所得比降、流量与允许比降、允许流量做了对比,从定量的角度提出了既安全、又经济的防渗方案:防渗墙厚度取0.8m,深度取打入破碎带5m。

In designing anti-seepage wall of reservoir’s dam foundation,there always have the inclination of over-security because of lack of testing or just using old analytical method. To solve this problem,this paper based on optimization theory,and by using the 2D finite element method,realized the optimal choice of the thickness and depth of dam foundation’s anti-seepage wall at Yanshan reservoir,in Henan Province. Firstly,the seepage fields of the dam foundations that have anti-seepage wall of different depth and height were modeled. And by comparing the calculating hydraulic gradients and seepage amount with the permissible hydraulic gradients and seepage amount,the optimized anti-seepage has been obtained as follows: the depth is 0.8 m,and the height is 5 m into the fractured area.