reza latifi - Department of Civil Engineering, science and research branch, Islamic Azad University, Iran

One of the most important elements of long-term behavior of earth dams is its stability while utilization. Stability of earth dam is influenced by water fluctuation especially while initial dewatering and rapid drawdown of reservoir. Since initial dewatering of steady state seepage or rapid drawdown of dam reservoir makes instability in earth dam slopes, we analyze stability of earth dam in various conditions. For this purpose, Yamchi earth dam was studied which is in Ardabil province. Upstream and downstream slopes of earth dams are one of the most important and main factors in its stability. These slopes are generally function of used soil materials, foundations, and its height. This slope is also dependent on type of earth dam. Stress-strain analysis was done by SIGMA/W software in GeoSlope package and stability analysis was also done by SLOPE/W program. The main issue in this study is analysis of earth dam in rapid drawdown condition and stability in various conditions of rapid drawdown of reservoir, semi-full and full reservoir

earth dam, rapid drawdown, stability, reservoir, Geoslope