Centrifugal model tests on stress characteristics of geomembranes placed on landfill slopes

The geomembranes placed on landfill slopes may suffer great tension and be damaged as a result of large settlement of waste. The tension and strain of geomembranes on the landfill slopes are studied using centrifugal model tests. Through FLAC simulation, it can be concluded that: (1) the model waste used in the test has good similarity with the prototype one, and the maximum settlement of model waste can reach 20%; (2) the geomembrane has tension and compression zones which are separated by the neutral point, and the position of the neutral point is affected by gradient and settlement. The tensile strain becomes smaller from the top of the slope to the neutral point, while the compressive strain decreases after increasing from the neutral point to the foot of the slope; and (3) the gradient and waste settlement are important factors to affect the development of tension, and the settlement affects tension by changing the mobilized interface strength. The tension is very small when the upside of geomembranes is smooth while the downside is rough because the external force is difficult to pass to the internal.