Seismic response and permanent displacement of landfills with liner interfaces and various foundation types

Abstract

The slip displacement along liner systems and the seismic responses of geo-structures significantly impact the seismic design of municipal solid waste (MSW) landfills. The influences of various factors, such as local underlying foundation conditions, the properties of the MSW, the properties of the foundation soils, and the shear strength of the liner interface, should be considered. In this paper, a preliminary single-degree-of-freedom model was developed to analyze the slip potential. This model demonstrated that the type of foundation significantly affects the seismic response of a landfill. A 2-D time-domain finite difference model was established, and the seismic responses and displacements were calculated for three different foundation types. In addition, the nonlinearity of the MSW and the underlying soil were considered by applying the equivalent linear procedure. The calculated results show that the slip along the liner interface exhibits two different modes: slip–stick and slip–slip. Furthermore, the shear strength of the interface and the foundation type significantly influence the overall seismic responses and the slip displacements of the landfills. Additionally, greater interface shear strengths may effectively reduce the slip displacement.