Reliability Analysis of CFR Dams under Earthquake Ground Motions


Ninth International Congress on Advances in Civil Engineering, Trabzon, Turkey, 27 - 30 September 2010, pp.1-10

  • Publication Type: Conference Paper / Full Text
  • City: Trabzon
  • Country: Turkey
  • Page Numbers: pp.1-10
  • Karadeniz Technical University Affiliated: Yes


In this study, reliability analysis of concrete-faced rockfill (CFR) dams under earthquake ground motion is carried out. In the numerical solutions, reliability analysis-finite element method combination is handled. Acceleration record of Erzincan earthquake in 1992 is used in the finite element analysis considering deconvolved base rock input model. In this model, the ground motion to be applied to the foundation base rock is obtained by deconvolution of the free-surface record. In the materially nonlinear analysis, Drucker-Prager material model is used for concrete slab and multi-linear kinematic hardening model is used for rockfill.
Geometrically nonlinearity is also taken into consideration. Viscous boundary conditions are defined in the finite element model for both foundation soil and reservoir water. The hydrodynamic pressure of the reservoir water is considered using 2D fluid finite elements based on the Lagrangian approach. Both welded contact and friction contact based on the Coulomb’s friction law are defined in the structural connections. Improved Rackwitz-
Fiessler Method is used with Response Surface Method in the reliability analysis. The tensile and compression stresses of the concrete slab are utilized in the implicit limit state functions. The probabilities of failure of the most critical points in the concrete slab are given according to reliability analysis. It can be stated that the probabilities of failure obtained from the model including friction contact in the joints are lower than those of welded contact. Also, the reliability of the concrete slab on the CFR dam decreases with considering hydrodynamic pressure.