This paper examines two needle-punched geosynthetic clay liners' water retention behaviour at high suction ranges using the vapour equilibrium technique where super-saturated salt solutions controlled the relative humidity. This study shows that the bentonite form and its mineralogy affect the absorption/desorption of GCLs and their corresponding water retention curves. In particular, a granular bentonite-based GCL was found to absorb more and release less water than a powdered bentonite-based GCL due to its higher montmorillonite content and larger pores. The water retention curves of both GCLs exhibited very little hysteretic behaviour at high suction. Repeated wetting-drying cycles shifted the WRCs of both GCLs slightly downward with minimal impact on their degree of hysteresis.

本文使用蒸汽平衡技术检查了两种针刺土工合成粘土衬垫在高吸力范围内的保水行为，其中超饱和盐溶液控制了相对湿度。该研究表明，膨润土的形式及其矿物学影响 GCL 的吸收/解吸及其相应的保水曲线。特别是，发现颗粒状膨润土基 GCL 比粉状膨润土基 GCL 吸收更多的水并释放更少的水，因为它具有更高的蒙脱石含量和更大的孔隙。两种 GCL 的保水曲线在高吸力下表现出非常小的滞后行为。重复的干湿循环使两个 GCL 的 WRC 略微向下移动，对其滞后程度的影响最小。