| Because there are frequent large earthquakes in Japan, seismic safety evaluation of dams against large earthquake motions is very important. On March 30, 2005, notification regarding the “Guidelines for Seismic Safety Evaluation of Dams (Draft)” systematically describing methods of evaluating seismic safety of dams subjected to large-scale earthquakes was given by Ministry of Land, Infrastructure and Transport (MLIT) of Japanese Government to organizations including all Regional Bureaus of the MLIT. According to “Guidelines”, the seismic safety of rockfill dam should be evaluated based on the amount of sliding displacement due to large earthquake motions. But, during the Niigata-ken Chuetsu Earthquake in 2004, a large settlement without sliding was observed at a rockfill dam at which consolidation settlement had almost finished before the earthquake. Thus, to accurately estimate the settlement due to large earthquake motions, the settlement should be reproduced by other method, such as deformation analysis based on cumulative damage theory.In this study, we calculated sliding deformation and settlement based on cumulative damage theory of earth core rockfill dam (ECRD) and concrete face rockfill dam (CFRD) under various conditions. Then we confirmed that the deformation pattern of an actual dam due to large earthquakes could be reproduced by deformation analysis method based on cumulative damage theory. |
