An evaluation of peak acceleration amplification coefficients in a CFR dam considering hydrodynamic pressure

Abstract

The aim of this paper is to present accelerations and peak acceleration amplification coefficients in a concrete faced rockfill (CFR) dam. For this purpose, Torul CFR dam is considered by using finite element method. Hydrodynamic pressure of the reservoir water is considered modeled using the fluid finite elements based on the Lagrangian approach. Deconvolution of surface accelerograms is taken into account in numerical solutions. Geometric, material and connection non-linearity are considered in the finite element analyses. The Drucker-Prager model and the multi-linear kinematic hardening model are used for concrete slab and rockfill, respectively, in the materially non-linear analysis. Non-linear behavior of the rockfill is obtained by the uniaxial stress-strain relation. The stress-strain curve of the rockfill is obtained using the shear modulusshear strain relation produced for the gravels. Different joints in the CFR dam are modeled with both welded and friction contacts. The friction in the joints is provided with contact-target element pairs based on the Coulomb's friction law. The accelerations in the bottom and crest of the dam are compared each other since welded and friction contact in dam-foundation interface. Then peak acceleration amplification coefficients are also obtained compared each other. According to numerical comparisons, when the rockfill behaves materially non-linear, the maximum horizontal accelerations and peak acceleration amplification coefficients decrease in the crest.