3D seismic response of concrete gravity dams considering effect of dam-foundation interface behavior

The seismic behavior of a concrete dam depends mainly upon its connection joints to foundation rock. The paper present aims to show the effect of dam-foundation interface behavior on the earthquake response of Oued Fodda concrete gravity dam, situated in high seismic activity zone of Algeria, considering bonded contact and friction contact. The latter is represented using contact elements based on Coulomb's friction law. To this end, a three-dimensional discretization of dam- foundation system using finite elements is used in different analyses. The hydrodynamic interaction between the reservoir water and dam-foundation system is implicitly taken into consideration by Westergaard approach using surface finite elements added to dam-fluid and foundation-fluid interfaces. The concrete material model is used to present the seismic cracking of dam concrete using Willam and Warnke failure criterion. Material and contact nonlinearity are considered in this numerical investigation. Drucker-Prager model is utilized in nonlinear analyses for dam concrete and foundation rock. The displacement response, principal stress and strain components as well as cracking response of the dam are investigated considering contact conditions along dam-foundation interface. The results obtained from bonded and friction contacts are compared to each other.