Effect of UV radiation on shear behaviour between geotextile and geomembrane interface

Geotextile/textured geomembrane (GTX/GMBT) liner at the bottom of the landfill will be exposed to ultraviolet (UV) radiation after installation and before being put into use, but the interface shear behaviour has not yet been studied. In this paper, based on laboratory UV accelerated weathering tests, the tensile behaviour of GTX and GMBT and the shear behaviour between the GTX/GMBT interface were studied. The experiment results showed that the Std-OIT value of aged GMBT was kept for a period of time and then dropped down due to the obstruction of the overlying GTX; the tensile strengths of GMBT exposed to UV radiation decreased, the GTX stiffness increased while both the tensile strength and elongation at break decreased. The peak and large displacement shear strengths between the GTX/GMBT interface both increased with the aging process. The compression behaviour between the aged GTX/GMBT interface decreased and the dilation phenomenon became obvious with the aging process during direct shear tests. The variation of shear-induced vertical displacement between virgin and aged GTX/GMBT systems based on the disturbance model was also established. This paper helps evaluate the variation of shear behaviour, compression, and shear-induced vertical deformation of GTX/GMBT exposed to solar radiation.