Effect of Using Vertical Drainage Column in Hemrin Dam on Factor of Safety Under Seismic Load

Recent years have seen an increase in the use of computer-based numerical models to test stability earth dams and simulate impact all factors that affect their safety. Geo-Studio software its sub-programs SLOPE/W, QUAKE/W are used determine safety dams, investigations dynamic analysis, a finite element serves as base do modeling for this study. The Hemrin Dam represents case study is regarded study's major focus. results showed values factor increased from (1.439) (1.583) when water level 8m, (1.365) (1.549) 16 m, (1.084) (1.317) maximum 32m, without with vertical drainage column, because pore pressure reduced effective stress increased. In Rapid drawdown column added, value decreases 1.371 1.306 initial time, while decreasing 1.406 1.363 second day rapid drawdown. These reductions result there delay between process reservoirs' dropping lowering on earthen dam's side. crucial dam drained using existing horizontal filters which eventually improve stress.