Comparison of Earthquake-Induced Pore Water Pressure and Deformations in Earthen Dams Using Non-Linear and Equivalent Linear Analyses

Abstract

Earthquake excitations often cause an increase in pore water pressure in contractive sands resulting in liquefaction, which can lead to catastrophic consequences. Therefore, it is imperative to assess the earthquake-induced excess pore water pressure and deformations to evaluate the post-earthquake serviceability of the important structures such as earthen dams. The analyses are usually performed using the equivalent linear method or the non-linear method. The purpose of this research is to evaluate and compare the excess pore water pressure and associated deformations predicted using these two methods of analyses. Two numerical models of a typical zoned earthen dam were subjected to two earthquake time-history data with significantly different frequency contents to comprehend the differences in the outcome. The analyses results are similar for dams with dense sand shells when subjected to low-intensity earthquake excitations with the predominant frequency significantly different from the first natural frequency of the structure.