防渗帷幕对污染物阻滞的数值模拟

基于地下水的渗透、弥散及源汇作用,不考虑污染物的生物降解及化学反应作用,分析研究了防渗帷幕对污染物的阻滞作用。用GMS建立了地下水渗流和污染物迁移三维耦合模型,采用数值分析方法,分析污染物在地下水中的迁移特征,研究防渗帷幕对污染物迁移的阻滞效应,比较研究了防渗帷幕渗透系数对污染物阻滞作用的影响。结果表明,在防渗帷幕厚度为0.5 m,渗透系数为0.01 m/d的情况下,污染物的衰减率为88.75%,渗透系数为0.001 m/d时,衰减率为94%。

Numerical simulation of retention of contaminant on curtain grouting

The retention mechanism of curtain grouting was analyzed based on permeability,diffusion and source/sink,without considering effects of biological degradation and chemical reactions.The coupled model of groundwater seepage and contaminant transport was established with GMS software,which takes convection and dispersion of contaminant into consideration.The transport characteristics of contaminant in groundwater environment were numerically analyzed,the retention effects of curtain grouting were researched,and the retention effects of different permeability coefficients of curtain grouting were also compared and researched.The results showed that the retention efficiency of the curtain grouting to contaminant migration was 88.75% after curtain grouting with thickness of 0.5 m and permeability coefficient of 0.01 m/d worked 360 d,while the contaminant retention efficiency was 94% after curtain grouting with thickness of 0.5 m and permeability coefficient of 0.001 m/d worked 360 d.