中文摘要：

多层土工合成材料复合衬垫的极限破坏面特性是垃圾填埋场稳定分析的重要问题,单一固定破坏面的观点已经被广泛接受。在多层土工合成材料复合衬垫的整体叠环式单剪试验后发现极限破坏界面并非单一固定,而是随着法向应力的变化发生由一个界面向另一界面转移,且在一定的法向应力范围内还可能同时出现两个具有相同剪切强度的极限破坏界面;多层土工合成材料复合衬垫中各层的剪切应力–位移曲线是硬化型的,衬垫系统的剪切强度总是低于极限破坏界面的剪切强度。试验结果表明,叠环式单剪仪能更正确和合理地模拟填埋场中的多层复合衬垫在加载过程中的实际剪切变形情况和复合衬垫中材料间的相互作用,从而能更好地揭示多层复合衬垫系统的整体剪切特性。

英文摘要：

The behavior of critical interface in geosynthetic multilayer liner system is an important problem in stability analysis of landfills.The point of single and fixed critical interface is widely adopted.By using the ring simple shear apparatus it is found that the critical interface in geosynthetic multilayer liner system is not single and fixed,and it can shift from one to another with changes of the normal,and two critical interfaces with the same strength may exist in a certain extent of the normal stress.The relationship between shear stress and displacement for the tested geosynthetic multilayer liner system is hardening behavior under various normal stresses.The shear strength of liner system is always lower than that of the critical interface.The test results show that the ring simple shear apparatus can better reveal the shearing behavior for the entire liner system and more reasonably simulate the interaction of various liner materials of a multilayer liner system.