This study investigated the impact of polymer elution on the interface shear strength between a smooth geomembrane (GMB) and two types of bentonite-polymer (B–P) geosynthetic clay liners (GCLs) containing linear and crosslinked polymers. Tests were also conducted with sodium bentonite (Na–B) GCLs as a control. Interface shear tests were conducted with dry, two-stage, and free hydration conditions with varying normal stresses. The results showed that under dry conditions, the displacement at peak strength and shear strength envelops of GMB/Na–B GCL and GMB/B–P GCLs were similar. However, the displacement at peak strength of GMB/B–P GCLs was higher than that of GMB/Na–B GCL under two-stage and free hydration. Meanwhile, the peak shear strength of the GMB/B–P GCLs showed a greater reduction than that of GMB/Na–B GCLs when transitioning from a dry condition to a free hydration condition at the same normal stress, particularly at higher normal stress. Loss on ignition (LOI) tests confirmed that there was a decrease in polymer loading of B–P GCLs after the shearing test, indicating polymer elution occurred during the shearing test. The result suggests that polymer elution had a significant effect on the GMB/B–P GCL interface shear strength, especially at higher normal stress.

本研究研究了聚合物洗脱对光滑土工膜（GMB）和两种含有线性和交联聚合物的膨润土聚合物（B-P）土工合成粘土衬垫（GCL）之间界面剪切强度的影响。还使用钠膨润土 (Na-B) GCL 作为对照进行了测试界面剪切测试是在干燥、两阶段和自由水合条件下以及不同的法向应力下进行的。结果表明，在干燥条件下，峰值强度和位移GMB/Na-B GCL 和 GMB/B-P GCL 的剪切强度范围相似。然而，在两阶段和自由水合下，GMB/B-P GCL 的峰值强度位移高于 GMB/Na-B GCL。同时，在相同的法向应力下，特别是在较高的法向应力下，当从干燥条件过渡到自由水合条件时，GMB/B-P GCL 的峰值剪切强度比 GMB/Na-B GCL 的峰值剪切强度有更大的降低。烧失量 (LOI) 测试证实，剪切测试后 B-P GCL 的聚合物负载量有所下降，表明剪切测试期间发生了聚合物洗脱。结果表明，聚合物洗脱对 GMB/B-P GCL 界面剪切强度有显着影响，特别是在较高法向应力下。