Behaviour of liquefaction for Darbandikhan Dam consequence impact of seismic load

Abstract Embankment dams are at risk of damage due to the impact of earthquakes. Rock-filled dam structures are especially vulnerable to earthquakes. To assess the impact of earthquakes, it is important to study liquefaction, which is a significant factor affecting the dynamic behavior of the dams. This study aims to determine the probability that the Darbandikhan rock-fill dam on the (Sirwan- Diyala) river in Iraq may liquefy using two-dimensional numerical modelling and finite element analysis, which is located in Alsulamaniyah north of the capital of Iraq, Baghdad 230 km. The simulation results are compared in terms of different water levels 434, 472, and 485m.a.s.l., different peak accelerations of the earthquakes (0.02, 0.04, 0.06 and 0.08) and different duration of earthquakes 25, 50, 75, and 100sec. As, a result the liquefaction zone increases with increasing upstream water level, acceleration, and duration. So, when the maximum operation water level was 485 m, the percentage of liquefaction area was 20% at peak acceleration of 0.08 g, and a duration of 100s. After that, the liquefaction zone decreases with a decreasing upstream water level of 472 m, for the same acceleration and duration of up to 12.5%. However, this percentage when the minimum water level of 434 m, acceleration 0.08g, and duration 100s, decreases by 65% from the liquefaction zone at elevation 485 m.a.s.l.