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 concretefaced 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 basedon the Lagrangian approach. Deconvolution of surface accelerograms is taken into account in numericalsolutions. 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 androckfill, respectively, in the materially non-linear analysis. Non-linear behavior of the rockfill is obtained bythe 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 weldedand friction contacts. The friction in the joints is provided with contact-target element pairs based on theCoulomb’s friction law. The accelerations in the bottom and crest of the dam are compared each other sincewelded and friction contact in dam-foundation interface. Then peak acceleration amplification coefficientsare also obtained compared each other. According to numerical comparisons, when the rockfill behavesmaterially non-linear, the maximum horizontal accelerations and peak acceleration amplification coefficientsdecrease in the crest.