填埋场导排层最大渗滤液深度影响参数显著性分析

为确定填埋场导排层最大渗滤液深度及各影响因素的显著性，首先基于扩展Dupuit假定推导了导排层渗滤液深度解析解，分析了不同渗滤液入渗强度情况下导排层渗滤液深度分布规律；其次将导排层渗滤液入渗强度、渗透系数、水平排水距离、坡度以及排水盲沟处水头5个主要参数采用正交试验分析法水平组合，通过方差分析对比了各参数对最大渗滤液深度的影响程度.研究结果表明：（1）推求的渗滤液深度解析解考虑了排水盲沟的实际水力状态，准确描述了渗滤液深度沿程分布特征；（2）渗滤液入渗强度和水平排水距离对导排层最大渗滤液深度具有显著性影响.研究成果可为填埋场导排层设计参数优化和预防渗滤液水位过高导致的填埋场失稳破坏提供技术支持.

Significance Analysis of the Influencing Parameters of Maximum Leachate Depth in Landfill Drainage Layer

In order to predict the maximum leachate depth in landfill drainage layer and determine the significance of its influening parameters,the following research work is carried out.Firstly,an analytical solution to leachate depth along drainage layer is obtained during leachate infiltration based on the extended Dupuit assumption;the distribution law of leachate depth along drainage layer is analyzed with different leachate infiltration intensity.Then,orthogonal design method is used for comparing the effectiveness of the five main parameters influencing maximum leachate depth,which are leachate infiltration intensity,permeability coefficient,horizontal drainage distance,layout slope as well as water head at the drainage blind ditch ,and the most influential parameters for changing maximum leachate depth are obtained.The variance analysis gives the degrees of impact for each parameter on the maximum leachate depth.The results show that:(1) the analytical solution of leachate depth obtained above considers the actual hydraulic state of the drainage blind ditch in the drainage layer more reasonably,and the distribution characteristics of leachate depth are accurately described;(2) leachate infiltration intensity and horizontal drainage distance have significant impact on the maximum leachate depth in the landfill drainage layer.The findings will facilitate the optimization of design parameters of landfill drainage layer and the prevention of landfill instability caused by high leachate depth.