Abstract:  The earth pressures behind a retaining wall are still studied by the geotechnical researchers and practitioners. This paper presents the research results of the earth pressures under the seismic conditions. The results are compared with the Rankine, and Coulomb earth pressure theories and it is found to be consistent. However, the existing earth pressure formulas are for the uniform and isotropic single soil layer, this paper presents the results for estimating the earth pressures for the multilayer backfill soils with different properties. The results indicate that the combined force of active earth pressures is higher than those of the Rankine and Coulomb earth pressures and the results are consistent with several previous results.

Key words: Earthquakes, Retaining Wall, Earth Pressures, Layered Backfills