Um estudo dinâmico de uma barragem arco gravidade considerando as juntas de contração

Abstract

The arch-gravity dams in roller-compacted concrete have stability and safety controlled by stresses. They are constructed as blocks separated by vertical contraction joints filled with mortar.In this contribution, a study is conducted to investigate the seismic response of a rolled compacted concrete arch gravity dam due to seismic loads, including the contraction joints and dam-reservoir-foundation interaction. To this purpose is considered an arch gravity dam, in preliminary study, to be built in a seismic zone of Turkey. The contraction joints are considered in a linear behavior, where the elastic properties of joints infills brings a reduction to the arch stiffness. The FluidStructure Interaction (FSI) is considered by modeling the reservoir with acoustic elements with the dynamic pressures obtained by the Eulerian approach. Considering a refined mesh obtained in a convergence study on a foundation stresses and dam body natural frequencies analysis. The dam-reservoir interaction is first validated in a natural frequencies and mode vibrations analysis. Then a comprehensive investigation of the seismic characteristics of the concrete arch-gravity dam-reservoir-foundation system is carried out based on a three dimensional dynamic analyses. The results present the contraction joints discontinuity influence, in displacements and tensions obtained in a seismic analysis.This information is important in dam project, defining concrete design, resistances distribution in structure body, as well in stability and safety evaluation.