Seismic Fragility of Rockfill Dams with Asphaltic Concrete Core

Many rockfill dams with asphaltic concrete cores have been built in recent decades. Therefore, it seems necessary to determine the seismic behavior of this type of dam against earthquake loads. This study aims to investigate the seismic behavior of this type of dam by obtaining seismic fragility curves. Seismic fragility is an efficient method for evaluating seismic behavior that is rarely used for rockfill dams. To this end, the Garmrood dam in Mazandaran Province in Iran has been selected as a case study and subjected to 10 different earthquake records to obtain fragility curves using incremental dynamic analysis. PGA as the earthquake intensity measure and the relative settlement ratio of dam crest as the dam damage measure are regarded. Also, three failure states of minor failure level, moderate failure level and severe failure level are considered for the damage measure. Finally, fragility curves were obtained, and the dam’s behavior was investigated. The results indicated that at the DBE earthquake level, the Garmrood dam is vulnerable at minor failure levels. Still, it is safer and more stable at moderate and severe failure levels. Also, at the MCE earthquake level, the Garmrood dam is almost entirely vulnerable at three damage failure levels.