Nonlinear and two-dimensional seismic response studies of solid-waste landfills

The seismic performance of municipal solid-waste landfills is examined using a fully nonlinear dynamic response program. Results from several landfill configurations, with different landfill properties and foundation conditions, are compared. The significant parameters which affect the seismic loading experienced by a landfill are identified. These parameters include the fundamental period of the waste fill {dollar}rm (Tsb{lcub}s{rcub}{dollar}-waste), the mean period {dollar}rm (Tsb{lcub}m{rcub}{dollar}-eq) and maximum horizontal acceleration (MHA) of the input earthquake rock motion, and the foundation conditions. Design charts are developed which aid in the estimation of the seismic loading for base and cover liner systems as a function of these parameters.; In light of the effect of an earthquake's frequency content on the seismic response of a waste fill, the frequency content of earthquake ground motions is examined using three simplified frequency content parameters (one of which was developed as part of this study, {dollar}rm Tsb{lcub}m{rcub}).{dollar} Models are developed to describe the magnitude, distance, and site dependence of these frequency content parameters. The models for active plate margin regions are based on 306 strong motion recordings from 20 earthquakes. The models for stable continental regions are based on a theoretical point source model. These simplified frequency content parameters, especially {dollar}rm Tsb{lcub}m{rcub},{dollar} are found to be useful in evaluating the seismic loading expected for a solid-waste landfill.; The procedures used to estimate seismically induced sliding displacements are examined, as they were developed and previously applied to earth embankments, not solid-waste landfills. Rigid sliding block analyses are performed, along with decoupled and fully coupled sliding block analyses using a distributed mass model with a mode shape appropriate for a soil system. Results from using several earthquake ground motions and a sinusoidal input indicate that a decoupled analysis does not always provide a conservative estimate of sliding displacement. A decoupled analysis does provide a half-order of magnitude estimate of coupled sliding displacement, which is generally conservative, but caution is warranted for particular cases. A rigid sliding block analysis can be significantly unconservative, and it should not be used.; The potential damage of solid-waste landfills during seismic events is examined through decoupled, seismically induced permanent sliding displacements. Base and cover liner sliding displacements calculated for different landfill configurations, input motions, and foundation conditions are presented and compared.; The reliability of one dimensional (1D) seismic response analyses to provide conservative estimates of seismic loading for the base and cover liner systems of solid-waste landfills is investigated. A comparison of the results from one dimensional and two dimensional (2D) response analyses reveal that 1D analysis provides conservative estimates of MHEA for deep sliding surfaces, but can predict unconservative accelerations along the surface of the landfill. (Abstract shortened by UMI.)...