垃圾填埋场防渗墙渗透性能有限元分析

A Finite Element Analysis of Permeability of Cut-off for landfill Site

垂直防渗系统是垃圾填埋场非常重要的部分之一,其作用在于可有效减缓污染物向周边土体及地下水渗透的速度。部分地区垃圾填埋场防渗墙因设计不合理,导致其防渗效果不能达到预期或在垃圾渗滤液的作用下发生破坏。目前对垃圾填埋场防渗墙的渗透性能研究较少,为了给垃圾填埋场垂直防渗系统的安全性及合理性提供理论支撑,使用有限元软件对江苏省内某垃圾填埋场的垂直防渗系统进行模拟分析。通过建立不同工况模拟了不同情况下垃圾填埋场中垃圾渗滤液的运移情况,并研究了防渗墙的防渗效果及安全性。模拟结果表明,防渗墙穿透墙体最快需15.86 a,符合垃圾场设计要求;在不同工况下的最大比降为5.16,说明墙体安全合理不会发生渗透破坏。

Vertical anti-seepage system is one of the most important parts of landfills.Its function is to effectively reduce the penetration rate of pollutants into surrounding soil and groundwater.Due to unreasonable design of landfill cut-off wall in some areas,its anti-seepage effect cannot meet expectations or the cut-off wall will be damaged under the action of landfill leachate.At present,there are few studies on the permeability of the landfill cut off wall.In order to provide theoretical support for the safety and rationality of the vertical anti-seepage system of landfills,finite element software is used to simulate the vertical anti-seepage system of a landfill in Jiangsu Province.The movement of landfill leachate under different conditions is simulated by establishing different working conditions,and the anti-seepage effect and safety of cut-off wall are researched.The simulation results show that it takes at least 15.86 years for leachate to penetrate the wall,which meets the design requirements.The maximum gradient under different working conditions is 5.16,which accords with national standards,indicating that the wall is safe and reasonable,and filtration erosion will not happen.