نوع مقاله : مقاله پژوهشی
نویسندگان
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
The effect of freeze-thaw cycles on hydraulic conductivity (HC) of compacted clay liner (CCL) and geosynthetic clay liners (GCLs) in water retaining structures and municipal solid waste landfills is a key issue in designing barrier systems in those structures. In this study the effect of freeze-thaw cycles on the hydraulic conductivity of a compacted clayey soil from Nazlou Region of Urmia City and a geosynthetic clay liner; and the impact of effective stress on the hydraulic conductivity change of clayey soil in these cycles were investigated. A flexible-wall triaxial hydraulic conductivity apparatus was used to measure the HC of the specimens subjected to freeze-thaw cycles. During the freezing process ice lenses grow in soil sample and when the ice lenses melt, a network of cracks is left and the HC increases. Increasing the effective stress reduces the increased hydraulic conductivity due to freeze-thaw cycles. The results show that on the contrary to compacted clayey soil, the application of intermittent freeze-thaw cycles does not significantly affect the HC of GCL even when GCL sample is subjected to extreme climatic conditions during which it continues to exhibit good performance as a hydraulic barrier.
کلیدواژهها [English]
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