考虑界面软化特性的垃圾填埋场斜坡上土工膜内力分析

为分析垃圾填埋场斜坡上防渗系统中的土工膜在上覆垃圾堆体重力作用下产生的拉应力，考虑土工膜-黏土界面的应变软化特性，通过建立土工膜受力的平衡方程获得了土工膜拉应力的解析解。与传统方法相比，该方法可分析土工膜-黏土界面不同位置所处的3种应力状态：弹性状态、软化状态及残余状态，从而使得垃圾填埋场斜坡上土工膜的受力分析更为合理。参数分析显示，当软化阶段的强度损失及残余位移与峰值位移的差值较小时，土工膜-黏土界面的峰值强度对土工膜最大拉应力的影响较小，而其残余强度是主要控制因素；而当土工膜-黏土界面的软化特征较明显时，则峰值强度和残余位移的影响也更为明显。另外，土工膜上覆堆体高度、斜坡坡度及土工膜锚固长度对土工膜拉应力也有较大影响。

Tension analysis of geomembrane in landfill slope considering interface strain-softening

In order to analyze the tension in geomembrane placed in landfill slope owing to the weight of municipal solid waste on the sealing liners, analytical solution of geomembrane tension based on equilibrium equation of geomembrane is gained with a strain-softening model of geomembrane-clay interface taken into account. In contrast to the conventional approach, this method can analyze three different stress states of the geomembrane-clay interface: elastic state, softening state and residual state; so it would be more reasonable for analyzing geomembrane tension. Parametric studies show that if the strength of loss in softening phase and the difference between residual displacement and peak displacement is small; the peak shear strength of the geomembrane-clay interface has a small effect on the geomembrane tension; and the maximal tension of the geomembrane mainly depend on its residual shear strength. Contrarily, if the softening characteristic of the geomembrane-clay interface is obvious; the influence of the peak strength and residual displacement is more notable. In addition, the height of the waste or the cover clay on the liners, the angle of slope and the length of geomembrane also have heavily effects on its tension.