دانلود رایگان مقالات عمران و معماری

Dynamic Behaviour of Sediment Deposits in Front of Concrete Gravity Dams

کریم عابدي- احمدرضا مصطفي قره باغي- مجيد پاسباني خياوي- , 5th National Congress on Civil Engineeringynamic Behaviour of Sediment Deposits in Front of Concrete Gravity Dams M. Pasbani Khiavi, A. R. M. Gharabaghi, K. Abedi 1- Ph. D. Student, University of Mohaghegh Ardabili, Ardabil, Iran 2- Assistant Professor of Civil Engineering, Sahand University of Technology, Tabriz, Iran 3- Professor of Civil Engineering, Sahand University of Technology, Tabriz, Iran pasbani@uma.ac.ir mgharabaghi@sut.ac.ir k_abedi@sut.ac.ir Analysis of dams is a complex problem due to the dam-reservoir-sediment interaction. An important factor in the design of dams in seismic regions is the effect of bottom sediment on the face of the dam as a result of earthquake ground motions. For an accurate analysis of sediment forces on the dam, the sediment is represented in a fluid-filled porous solid on the basis of the Biot theory of wave propagation in poroelastic media while the water is taken as a compressible, inviscid and irrotational fluid. In Biot formulation, the equations of motion of the soil mixture are coupled with the global mass balance equations to describe the realistic behavior of sediment. Because of irregular geometry, the sediment is generally treated as an assemblage of finite elements. The weighted residual standard Galerkin method with 8-node elements is used for developing finite element model. The analysis is carried out in time domain considering earthquake excitation and gravity loading. Newmark time integration scheme is developed to solve the time-discretized problem which is an unconditionally stable implicit method. Finally, the seismic behavior of sediment due to ground motion is investigated. Keywords: Gravity dam, sediment, finite element, earthquake