In landfills, shear creep of the liner interface occurs after some shear displacements under the influence of a sustained load from waste. In this paper, an apparatus was developed to conduct shear creep tests on interfaces after different initial shear displacements, and experimental investigations were performed on the shear creep behavior of the geotextile and geomembrane interfaces pre/post peak strength. The results demonstrated that the initial instantaneous displacement and the steady displacement rate at the interface increased with increasing shear stress. The initial instantaneous displacement at the geomembrane‒geotextile interface in the post-peak tests was reduced compared with that in the pre-peak tests, whereas the displacement rate at elevated shear stress levels was greater in the post-peak tests than in the pre-peak tests. The creep behavior of the interface was influenced by both the initial shear displacement and the material interaction. An analysis of the Nishihara model revealed that the shear modulus of the Hooke body at the interface increased with increasing shear stress in the pre-peak test, whereas it decreased in the post-peak test as the shear stress increased. The difference in calculated creep time from the 30-day test results and from 3-day creep test results was approximately 8.9%.

中文翻译：

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非织造土工布与土工膜峰前/后峰强度之间的界面剪切蠕变行为


在垃圾填埋场中，衬垫界面的剪切蠕变发生在一些剪切位移之后，受到废物持续载荷的影响。本文开发了一种在不同初始剪切位移后对界面进行剪切蠕变试验的装置，并对土工布和土工膜界面峰前/后强度的剪切蠕变行为进行了实验研究。结果表明，初始瞬时位移和界面处的稳态位移速率随着剪切应力的增加而增加。与峰前测试相比，峰后测试中土工膜\土工布界面处的初始瞬时位移减小，而峰后测试中剪切应力水平升高时的位移速率大于峰前测试。界面的蠕变行为受初始剪切位移和材料相互作用的影响。对 Nishihara 模型的分析表明，在峰前试验中，界面处 Hooke 体的剪切模量随着剪切应力的增加而增加，而在峰后试验中，随着剪切应力的增加而降低。根据 30 天的测试结果和 3 天的蠕变测试结果计算出的蠕变时间差异约为 8.9%。