摘要
地下水浸润线的计算与控制直接关系到堤坝、基坑、边坡工程的施工安全。该文基于Signorini型变分不等式方法自主开发出有限元渗流计算程序,对复杂开挖条件下太湖隧道明挖基坑边坡进行渗流分析,计算出不同工况下基坑边坡的地下水浸润线,并提出防渗措施布置的优化建议。研究表明:地下水浸润线在围堰及止水帷幕中分布陡峻,而在2-3粉土层中分布相对平缓,围堰、止水帷幕与降水井对地下水浸润线均起到显著的控制作用;不利工况下地下水浸润线在围堰或边坡上溢出,渗流溢出部位的最大渗透坡降为1.65,单宽渗漏量为6.25 m3/d;建议采取加深钢板桩围堰或将止水帷幕布置在围堰等措施,以达到完全隔断2-3粉土层与降低地下水浸润线的目的。
The calculation and control of groundwater saturation line is directly related to the construction safety of embankment,foundation pit and slope engineering.Based on the Signorini type variational inequality method,in this paper,a finite element seepage calculation program independently is developed,the seepage of the open excavation foundation pit slope of Taihu tunnel under complex excavation conditions is analysed,the groundwater saturation line of the foundation pit slope under different working conditions is calculated,and the optimization suggestions for the arrangement of seepage control measures are put forward.The results show that the groundwater saturation line is steep in the cofferdam and water stop curtain,but relatively gentle in the 2-3 silt layer,and the cofferdam,water stop curtain and dewatering well all play a significant role in controlling the groundwater saturation line;Under the adverse conditions,the groundwater saturation line overflows on the cofferdam or slope,the maximum seepage gradient of the seepage overflow part is 1.65,and the single width seepage volume is 6.25m3/d;It suggests to deepen the steel sheet pile cofferdam or arrange the water stop curtain in the cofferdam to completely cut off the 2-3 silt layer and reduce the groundwater saturation line.
作者
周欣
吴建
周志芳
庄超
祁长青
Zhou Xin;Wu Jian;Zhou Zhifang;Zhuang Chao;Qi Changqing(Construction Bureau of Traffic Engineering in Jiangsu Province;School of Earth Sciences and Engineering,Hohai University)
出处
《勘察科学技术》
2020年第1期40-45,55,共7页
Site Investigation Science and Technology
基金
国家自然科学基金资助项目(NO.41572209)。
关键词
隧道工程
浸润线
变分不等式法
基坑边坡
控制
tunnel engineering
saturation line
variational inequality method
foundation pit slope
control
