Dynamic properties of solid waste based on back-analysis of OII landfill

Back-analyses of the recorded seismic response of the Operating Industries, Inc. landfill were performed to estimate strain-dependent shear modulus reduction and material damping relationships for solid waste. Two-dimensional dynamic finite element analyses were performed using the accelerograms from five earthquake events. The sensitivity of the computed results to variations in shear wave velocity, shear modulus reduction, damping, and Poisson's ratio was examined. The recorded and calculated motions at the top of the landfill were compared through an objective statistical analysis of the computed and recorded acceleration response spectra. Statistically significant findings from the analysis indicate that strain-dependent shear modulus reduction and material damping relationships for the solid waste at this site ate best characterized by those of a medium plasticity clay.