生活垃圾非饱和渗透性质测定的多步出流方法

传统土壤渗透性测量方法直接测量填埋生活垃圾的渗透性质误差较大.本实验现场测定六里屯填埋场原状垃圾土饱和含水率和饱和渗透系数,其平均含水率随填埋深度增加而增大,平均渗透系数为0.018 5mm·s^-1.在保证容重相同条件下,用多步出流法实验室测定扰动样品水分特征曲线和非饱和渗透系数.运用渗压出流和理论拟合测试技术,为建立渗透参数的随机分布模型提供参数测定方法.实验结果与模型显著相关.通过实验及模型模拟,揭示了填埋垃圾水分特征曲线的变化规律,证明多步出流法是适用于填埋场非饱和渗透性质测定的有效方法.

Multistep Outflow Method for Determination of Unsaturated Hydraulic Conductivity of Municipal Solid Waste

Traditional method for soil permeability measurement causes important errors when it is used in municipal solid waste(MSW) experiment.The in-situ saturated water content and hydraulic conductivity were measured at Liulitun landfill. It was tested that the average water content increased downward and the average hydraulic conductivity was 0.018 5mm·s^-1. On the same condition of density,water retention curve and unsaturated hydraulic conductivity were determined with multistep outflow method in laboratory.Multistep outflow method,together with successive simulation,is used in the paper to provide parameter measurement for distribution models.The model is remarkably correlative to experiment data.On the basis of lab data and later simulation,changing rules of water retention curve are disclosed,and the method is proved to be effective to measure unsaturated hydraulic conductivity of municipal solid waste.