Validation of a numerical modelling technique for multilayered geosynthetic landfill lining systems

It has become common practice to conduct numerical analyses to assess the stability and integrity of side slope landfill lining systems; however, information that can be used to validate such models is extremely limited. This paper contains data from a series of large-scale laboratory tests containing geosynthetic elements of a multilayered lining system exposed to downdrag forces from a compressible synthetic waste material (rubber crumb). These data are compared to the results from numerical analysis of the same problem. The numerical results are from initial best estimate analyses, with interface and synthetic waste properties derived from a laboratory testing programme and geosynthetic material properties from manufacturers. The observed trends of tensile stresses in the geosynthetics and relative displacements at interfaces in the laboratory testing are reproduced by the numerical models to an acceptable degree of accuracy that would be appropriate, using site-specific input data, for use in commercial design.