الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Storage earth dams are mega structures their may failed during earthquakes may cause serious consequences from direct loss of life to indirect economic losses. The seismic vulnerability of earth dams and the potential consequences of their failures depend on their seismic response. Seismic responses appear in slope failure, piping, and displacement /settlement resulting from weak soil and/or liquefaction of loose sands. Earth dams failure may occur due to different reasons such as structural instability conditions and liquefaction failure due to earthquakes. The determination of factor of safety for the dam slopes stability, under seismic loads, is vital to ascertain the dam overall safety. In this work, Finite Element modeling is employed for simulating slope stability and stress analysis of earth dam problems via GEOSTUDIO, PLAXIS and ANSYS software. The dam numerical model is calibrated and 2-D numerical model is employed to analyze stability of five selected cases of study; selected cases are considered of liquefaction failure. Obtained results in this research ascertain the importance of considered factor of safety before and during earthquake excitations on liquefaction area determination. In this work simulation of and Bilate dam and dam founded on Nile deposits, Ethiopian cases of study; Conclusions that critical scenario of dam founded on Nile deposits is cracks in concrete upstream slab for slope stability. The most values of (ru) ratio at upstream zone in case of original section of Dam founded on Nile deposits . Lowering of reservoir level (Rapid draw down) reduces additional shaking load from reservoir on upstream slope and increase the stability, it is more safe and no liquefied in alluvium layer. Scenario (1) cracks in upstream slab are the most values of (ru) ratio at downstream zone, sudden DROP in the distribution of horizontal and vertical stresses at distance (x) along the dam that occurs at the place where the soil is most liquefiable, as well as the largest value of excess pore water pressure.