The environmental performance of landfill liners is primarily controlled by the fate and transport of leachate constituents from the landfill leachate. Hence, hydraulic conductivity of the liner is a key factor when selecting material for lining systems. Hydraulic conductivity is influenced not only by the properties of the porous media but also the permeant liquid. There are many studies where elevated temperatures of waste and leachate have been reported due to the aerobic decomposition of the organic fraction of waste. At elevated temperatures, soil structure and permeant viscosity change. However, there is very little experimental data on hydraulic conductivity of clays or geosynthetic clay liners (GCLs) permeated at elevated temperatures.; The primary objective of this study was to evaluate the effect of elevated permeant temperature on hydraulic conductivity of GCLs. An experimental setup was designed to meet the research objectives. The key conclusions are: (1) There is a 2 to 3 fold increase in the hydraulic conductivity of GCLs when permeated with DI water, tap water, or 0.1 M CaCl2 solutions at 80 °C when compared at 21 °C; and (2) this increase in hydraulic conductivity is primarily due to decrease in the viscosity of the permeant. Hence, hydraulic conductivity of GCLs at elevated permeant temperature can be estimated by applying the viscosity correction specified in ASTM D 5084 to the hydraulic conductivity measured at a room temperature.
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机译：垃圾填埋场衬板的环境性能主要受垃圾填埋场渗滤液中沥滤液成分的命运和运输的控制。因此，在为衬里系统选择材料时，衬里的水力传导性是关键因素。导水率不仅受多孔介质的特性影响，而且还受渗透液体的影响。在许多研究中，由于废物有机部分的好氧分解，已报告了废物和渗滤液温度升高的报道。在高温下，土壤结构和渗透粘度会发生变化。然而，关于在高温下渗透的粘土或土工合成的粘土衬里（GCL）的水力传导率的实验数据很少。这项研究的主要目的是评估渗透温度升高对GCL的水力传导率的影响。设计了实验装置以满足研究目标。主要结论是：（1）与21°C相比，在80°C下用去离子水，自来水或0.1 M CaCl2溶液渗透时，GCL的水力传导率增加了2到3倍； （2）水力传导率的增加主要是由于渗透液粘度的降低。因此，可以通过将ASTM D 5084中规定的粘度校正应用于室温下测得的水力传导率，来估算GCL在升高的渗透温度下的水力传导率。
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