Quantitative assessment of concrete gravity dams in terms of energy using damage index for near-fault

Seismic assessment of concrete gravity dams is mainly conducted using capacity estimation of limit states or determination of damage indexes. Within the context of performance-based earthquake engineering (PBEE), damage measure (DM) refers to physically observable DSs, which can be subsequently related to repairs. Hence, the propensity for potential failure modes of concrete dams should be quantified. The main purpose of this article is the quantitative seismic assessment of concrete gravity dams using an energy-based damage index. Therefore, by selecting Pine Flat gravity dam as a case study, incremental dynamic analysis has been performed on the dam-reservoir-rigid foundation system, under near-fault records with forward directivity effects. Then, limit states (LSs), damage levels and total dynamic capacity of the structure were determined by energy-based parameters. After that, damage states (DS) of the dam were determined and using an energy-based damage index (DIE), the determined damage states were quantified. In the next step, performance levels of the dam were defined and the identified DSs along with corresponding DIE ranges were assigned to the relevant performance levels. The results showed that mentioned damage index effectively has estimated the damage state of the dam quantitatively.