Interface Friction Properties of Multi-layered Geosynthetics

Abstract

Multi-layered geosynthetic liner is often used in landfill. In a design practice, it is very important to know shearing behavior of each geosynthetics on side slope of the landfill. In this paper, new shearing test device which has two shearing interfaces was developed, where shearing force was applied to the upper-layer and tensile forces induced in middle and lower-layer were measured respectively through load-cell. 10 cases of test were performed varying two interfaces friction, normal force and rigidity of second layer.
Consequently, it was founded that
(1) Tensile force induced in the middle-layer increase with increasing of rigidity of the middle-layer and with decreasing of normal stress given on the interface.
(2) Tensile force can mobilize even when the interface friction between upper and middle-layer is smaller than the one between middle and lower-layer. This demands a revision of Koerner's method relating to stress transmission among geosynthetics.