Monitoring Seepage through Dam under Consolidation Using the Finite Element Method, Case Study: Karkheh Dam

The monitoring of an earth dam refers to the dam’s performance in different construction stages, starting with impoundment followed by the exploitation period, which can be achieved in different fields such as seepage and subsidence analysis. This research analyzed Karkheh storage dam’s seepage behavior using the finite element method under various scenarios assuming saturated flow, saturated-unsaturated flow, and saturated-unsaturated flow under consolidation in steady and unsteady conditions. The 17-year data obtained from the Karkheh dam’s piezometer instrumentation in five sections of the dam’s body and foundation were used to improve the accuracy of the parameters and adapt the analyses results to the actual dam conditions. Subsequently, seepage analysis comprising calibration and validation of the numerical model in two-dimensional and three-dimensional states using Seep/w and Seep3D software was conducted under the considered scenarios. Finally, a complete numerical model was obtained based on the actual dam conditions. The results show that three-dimensional flow analysis in the unsteady state under consolidation is more accurate than the two-dimensional state with a 23.5% lower error rate than the 2D approach.