Seismic stability of reinforced soil structure constructed after the mid Niigata prefecture earthquake

The mid Niigata prefecture earthquake in 2004 damaged a number of structures including embankments, earth slopes and retaining walls. This paper describes numerical techniques to evaluate the performance of structures constructed before and after the mid Niigata prefecture earthquake. Deformation analysis was conducted by the Newmark's sliding block analysis that implements the ground water level estimated by the seepage analysis and the response acceleration of the structure subjected to the earthquake by the finite element analysis. From the results of the current numerical analysis, the instillation of the reinforcement can increase the stiffness of the reinforced soil, resulting into the decrease of the deformation at the crest of the structure. The numerical analysis in this study revealed that the performance of the reinforced structure constructed after the earthquake significantly improved as compared to that of the structure constructed before the earthquake.