Abstract
As landfill cap covers with waterproof, gas permeability and construction durability, we have developed geocomposites (GCs) that nonwoven geotextiles are laminated to the both surfaces of the porous sheet and their basic performances have been investigated by laboratory and field tests. In this study, interface friction characteristics between soil and GCs, which indicate slope stability when GCs are practically applied as landfill cap cover, were evaluated by interface shear tests. Results show that interface shear strength and friction characteristics are increased by improving surface roughness and rigidity of nonwoven geotextiles. It was also found that compaction degree of soil affects interface shear strength between soil and GCs.