Tomohiro Ishizawa

Case Studies on Seismically Induced Slope Failures in Terms of Energy

An energy approach proposed to make a simple evaluation of travel distance of debris has been applied to seismically induced slope failures during recent two earthquakes. Mobilized friction coefficients have been back-calculated, revealing their strong dependency on initial slope inclinations. The friction coefficients are found to become smaller than the initial slope inclinations in gentler slopes presumably due to seismic shock. The friction coefficients also tend to decrease with increasing volume of failed slopes, which is consistent with previous case studies on huge landslides. Most importantly, the average thickness of failed soil mass seems to serve as a good indicator for specifying the mobilized friction coefficient to predict the travel distance using the energy approach.