生活垃圾填埋场的稳定性数值模拟及分析

Numerical Simulation and Analysis of the Stability of a Municipal Solid Waste Landfill

摘要: 生活垃圾填埋场是一个不稳定的灾害体，很容易发生滑坡现象。一旦填埋场发生失稳滑移，会导致填埋堆体内大量的渗滤液和填埋气体溢出，对下游造成灾难性的环境污染。本文以浙江的一个生活垃圾填埋场为例，利用Geo-Studio数值模拟软件的Slope和Seep模块，建立了相应的填埋场几何模型，利用室内试验测出的土工参数对模型参数进行取值，对填埋场边坡稳定性进行分析。统一采用Bishop法计算该填埋场在不同影响因素下的最小安全系数Fs和可能的滑移坡面。结果表明，填埋场的安全系数随着水位线的下降、抗剪强度参数的增大而增大，随着降雨时间的增加而逐渐减小，随着沉降的增大先增大后减小。本文的研究结果可为城市生活垃圾填埋场的污染治理提供基础数据，为稳定性分析提供有价值的信息。

Abstract: The solid waste landfill is an unstable disaster body, which is prone to landslides. Once the landfill site experiences instability and sliding, it can lead to a large amount of leachate and landfill gas overflowing from the landfill site, causing catastrophic pollution to the downstream environment. Taking a solid waste landfill in Zhejiang Province as an example, this paper established the corre-sponding geometric modeling of the landfill through the Slope and Seep modules of the numerical simulation software Geo-Studio, and analyzed the slope stability of the landfill using the geotech-nical parameters measured in laboratory tests to determine the values of model parameters. The Bishop method was used to calculate the minimum safety factor Fs and possible sliding surface of the landfill site under different influencing factors. The results indicate that the safety factor of the landfill gradually increases with the decrease of the water level, the increase of waste shear strength parameters, decreases with the increase of rainfall time, and increases initially and de-creases with increasing settlement. The research results of this paper can provide basic data for the prevention of environmental pollution of solid waste landfills, and provide valuable references for stability analysis.