Back analyses of case histories and model tests on seismic stability of retaining walls

摘要

Back-analyses of case histories on seven retaining walls for railway embankments damaged by the 1995 Hyogoken-Nanbu earthquake were conducted based on pseudo-static and limit-equilibrium approach. Critical seismic coefficients yielding a safety factor of unity were obtained under two different conditions using conservative and peak soil strength values, respectively. A possible correlation between these values and the field behavior was investigated. Tilting and shaking table tests were also performed on six small-scale models of different types of retaining walls. Stability of these model walk observed under the two different loading conditions was compared to each other and to the calculated critical seismic coefficients using peak soil strength values. The relative seismic performance of these model walls observed in the shaking table tests was smaller for the leaning- and gravity-type walls than for the cantilever-type and reinforced-soil walls. This tendency was qualitatively consistent with the field behavior.