Effects of local site conditions on the seismic response of municipal solid waste landfills

Over the last decade, the seismic response of landfills made of municipal solid waste has drawn attention mainly due to the environmental and public-health issues that could be raised in the event of a failure. Nevertheless, there are several associated technical issues that have not been adequately investigated. One of these is the impact of local site conditions on the earthquake-induced accelerations and, thereby, on the seismic design of a landfill. This study presents the results of a parametric numerical simulation that has been performed in order to examine the effects of local site conditions on the dynamic response of a typical landfill. Emphasis is given on the special characteristics of ground motion, while the material nonlinearity of both soil and waste is taken into account by an equivalent-linear procedure. Results indicate that local site conditions may play a significant role in the seismic response of a landfill. However, this role cannot be judged a priori as beneficial or detrimental, as it depends not only on soil conditions and seismic excitation, but also on the material and geometric characteristics of the landfill.