Abstract The paper focuses on the evaluation of the shear strength in conditions of low normal stress of various geosynthetic-geosynthetic interfaces, which are typical of landfill cover systems, by means of the inclined plane test, with the aim of studying the friction mobilisation in relation to various kinematic behaviours. The results of three different methods to evaluate the angle of friction were analysed, together with the sensitivity of the interfaces in relation to the wear effect and the influence of the state of hydration. The results showed very different responses of the interfaces to the shear stress, which involved three main types of sliding mechanisms, referred to as sudden, gradual and uneven sliding. Another outcome observed was that the shear strength of geosynthetic-geosynthetic interfaces cannot always be properly characterised following the procedure proposed by the European standard for soil-geosynthetic interfaces (EN ISO 12957–2), since the actual mobilised kinematic behaviour should be taken into consideration. In this regard, the paper provides some hints on the choice of the more representative parameter of friction for each type of sliding. A particular focus was given to the case of gradual sliding interfaces, for which the static friction is difficult to detect due to the very slow movements; for practical purposes, the design friction of these interfaces should be evaluated by using an adequate safety factor with respect to the friction evaluated at 1 mm of displacement.

中文翻译：

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土工合成材料界面摩擦的斜面试验表征

摘要 本文重点通过斜面试验对垃圾填埋场覆盖系统中典型的土工合成材料-土工合成材料界面在低法向应力条件下的抗剪强度进行评估，目的是研究相关的摩擦动员。到各种运动学行为。分析了评估摩擦角的三种不同方法的结果，以及与磨损效应和水合状态影响相关的界面敏感性。结果显示界面对剪切应力的响应非常不同，其中涉及三种主要类型的滑动机制，称为突然滑动、逐渐滑动和不均匀滑动。观察到的另一个结果是，土工合成材料界面的剪切强度不能总是按照欧洲土壤-土工合成材料界面标准 (EN ISO 12957-2) 提出的程序正确表征，因为应考虑实际移动的运动学行为. 在这方面，本文提供了一些关于为每种类型的滑动选择更具代表性的摩擦参数的提示。特别关注渐变滑动界面的情况，由于运动非常缓慢，静摩擦难以检测；出于实际目的，这些界面的设计摩擦力应通过使用足够的安全系数来评估，相对于在 1 毫米位移处评估的摩擦力。