Evolution of earthquake-resistant design of dams – case studies

Abstract

The purpose of the publication is to present the evolution of earthquake-resistant dam design through case studies where structures have been damaged or destroyed by earthquakes. It can be stated that such cases are very rare, and the rupture of a valley dam can have unforeseeable consequences. A detailed presentation of these rare events (damage and failure) helps to understand the design and construction deficiencies against seismic effects. In some cases, performing “back analysis” made it possible to reconstruct the events, understand the failure mechanism and develop more accurate safety approaches. One of the most documented cases is the damage of the San Fernando dams in 1971, when two reservoir dams’ upstream sides suffered massive slides. The only recorded dam failure happened at the Fujinuma dam during the 2011 “great Tohoku” earthquake. Based on a summary of the international literature, the study draws attention to the fact that earthquake-resistant design is essential for dams to tackle dynamic loads and seismic effects. The design procedure includes construction issues as well as structural detailing and complex dimensioning. Specific calculation methods are also dealt with in Eurocode 8 and in a previous publication by the authors.