A Study of the Seismic Behavior Of Geosynthetic Reinforced Walls in Japan

A significant effort is being made in Japan to improve seismic design of geosynthetic reinforced soil structures. This paper gives a brief review of a seismic design method which is based on a limit-equilibrium method of analysis. The method results in two separate equations to determine the factor of safety for geosynthetic reinforced embankments and retaining walls under earthquake loading. The involvement of the author in developing an empirical procedure to estimate displacements under seismic loading is described. Instrumented wall model tests with light-weight block wall facings were conducted using a shaking table and a centrifuge. The effects of soil density, geosynthetic length and strength on the magnitude of horizontal wall displacements were investigated experimentally. An empirical relationship to estimate horizontal wall displacements is proposed. Light-weight facing blocks were found to be effective in reducing displacements in geosynthetic reinforced soil wall structures under earthquake loading.