Deformation characteristics and design of geosynthetic liner system subjected to local subsidence

Taking into account the soil-arching effect and large deformation of liners,a model of force and deformation analysis was presented for the geosynthetic liner system subjected to local subsidence.Taking the maximum tensile strain of the liner system as the control parameter,the design method of the liner system resisting the local subsidence was given for the engineering application.Effects of shear strength of the liner system,the thickness,the bulk density,the effective internal friction angle of the overlaying soil and the structural configuration of the liner system were studied using the proposed model.It was shown that the thickness,the bulk density and the effective internal friction angle of the overlaying soil could greatly influence the force and deformation of the liner system,and the tensile strain of the liner system mostly depended on its tensile stiffness.The coving system and the liner system between the old and expanded landfills were designed to resist the local subsidence for the vertical expansion of a given valley landfill,and the reasonable structural configurations of the coving system and the liner system were recommended.