摘要
为研究粤西地区某水库土石坝体渗流特征以及防渗墙最优设计方案,利用COMSOL仿真计算分析了渗流特征参数变化规律。对比了有、无防渗墙条件下坝体渗流场特征,当有防渗墙时,下渗流活跃性显著降低,渗流安全性提高,其中有防渗墙条件下坝体上、下游面最大孔隙水压力降幅达60%。分析了防渗墙设计参数对坝体渗流特征参数影响规律,防渗墙深度、厚度均与坝基单宽渗流量、防渗墙后水头值、坝脚逸出点渗透坡降为负相关关系,但不同厚度下防渗墙底部渗透坡降随深度为先减后增变化,防渗墙深度8 m时的墙底部渗透坡降为各厚度下最低。综合渗流安全性与工程经济性,防渗墙深度2 m、厚度80 cm时为最佳方案。本文研究为水利工程中防渗墙设计、土石坝体渗流分析提供一定参考。
In order to study the seepage characteristics of an earth-rock dam of a reservoir and the optimal design for its cut-off wall in western Guangdong,the change rules of seepage characteristics parameters were analyzed by COMSOL calculation.By comparing the seepage field characteristics of the dam with and without the cut-off wall,the seepage activity is significantly reduced and the seepage safety is improved under the cut-off wall.At the same time,the maximum pore water pressure on the upper and downstream surfaces of the dam reduced by 60%.The influence of the design parameters of the cut-off wall on the seepage characteristic parameters of the dam body was analyzed:the depth and thickness of the cut-off wall were negatively correlated with the single-width seepage flow of the dam foundation,the head value behind the cut-off wall,and the seepage slope at the dam foot escape point.However,the seepage slope at the bottom of the cut-off wall at different thicknesses changed with the depth firstly decreased and then increased.When the depth of the cut-off wall was 8 m,the seepage slope at the bottom of the wall was the lowest at different thicknesses.Integrating seepage safety and engineering economy,the best solution is that depth of the cut-off wall is 2 m and the thickness is 80cm.This paper provides references for the design of the cut-off wall and the seepage analysis of the earth-rock dam in water conservancy projects.
作者
宁威锋
NING Weifeng(Jiangmen Keyu Water Conservancy Planning and Design Consulting Co., Ltd., Jiangmen 529000, China)
出处
《水利科学与寒区工程》
2021年第2期28-33,共6页
Hydro Science And Cold Zone Engineering
关键词
COMSOL
土石坝
渗流特征
防渗墙
设计
COMSOL
earth-rock dam
seepage characteristics
cut-off wall
design
