填埋场连续型排水结构中最大饱和深度的计算

The Calculation of Maximum Saturated Depth in Landfill with Continuous-slope Configuration Drainage System

确定填埋场中的最大饱和深度是进行渗滤液导排系统设计的关键技术参数。针对倾斜场地上的连续型排水结构,基于流量连续条件、Dupuit假设与扩展Dupuit假设,在稳态渗流下,分别建立了浸润线方程,采用数值方法进行计算。通过变动参数计算与分析表明,当场地坡度小于10%时,可采用Dupuit假设下的计算方法进行计算。对于采用土工排水网的连续型排水结构,土工排水网导水率与场地坡度为控制填埋场最大饱和深度的重要因素;保护层渗透系数与入渗率对于控制排水系统的排水效率具有不可忽视的作用。同时比较了水平场地上的锯齿型与连续型排水结构的排水效率,表明前者优于后者。

Maximum saturated depth is an important parameter in designing of landfill leachate dramage systems. Dased on the groundwater flow continuity principles, Dupuit assumptions and extend Dupuit assumptions, phreatic surface governing equations were established over the landfill with slope liner in continuous-slope configuration drainage system, respectively. These equations were solved by numerical calculation. Though computation and analysis of change parameters, the results indicate that Dupuit assumptions can be used to calculate the maximum saturation depth as the slope of landfill liner is less than 10%. When geonet is employed in continuous-slope configuration drainage system, transmissivity of geonet and slope of landfill liner are important influence factors for maximum saturation depth, hydraulic conductivity of protect layer and impingement rates for efficiency of drainage system can＇t be ignored. At the same time, compared the efficiency of continuous--slope with saw--tooth configuration＇s in level landfill liner, the results show the former is better than the latter.