Dynamic shear behavior of geosynthetic-soil interface and numerical implementation considering chemical effect

Geosynthetics are normally used in waste landfill sites for various purposes. Geosynthetics in soil compose geosynthetic-soil interface by contacting soil particles. The remarkable differences of the intrinsic material characteristics at the interface induce complex stress-strain behaviors. In particular, the chemical elements in the leachate affect the dynamic shear behavior of geosynthetic-soil interfaces. In this study, the dynamic shear tests of geosynthetic-soil interfaces are performed using multi-purpose interface apparatus (M-PIA), which was recently developed in South Korea. The specimens are submerged into acid, neutral and basic solutions for a period and the effect of chemical element is analyzed. Test results show different responses according to the pH value of the solutions. The Disturbed State Concept (DSC) and disturbance function have been employed to suggest better approaches to analyze the dynamic shear behavior of the interface considering chemical effect. Consequently, the numerical implementation of the modified DSC equations has been performed.