Energy-Based Evaluation of Earthquake-Induced Slope Failure and Its Application

Slope failures during the 2004 Niigata-ken Chuetsu earthquake and their mechanisms are discussed herein. Slopes are composed of weak sedimented rock of alternating layers of strongly weathered sand stones and mud stones. Bedding planes had a strong effect on the failure mechanisms. An energy approach for run-out distance of failed soil mass in view of earthquake energy, together with potential energy, is applied to representative slope failures during the earthquake. It is found that the equivalent friction coefficient back-calculated by the energy approach is strongly dependent on the initial slope inclination. However, the absolute value of the former is smaller than the latter, indicating the failed soil mass initially accelerated.