Computation of Seepage and Exit Gradient through a Non-Homogeneous Earth Dam without Cut-off Walls by using Geo-Slope (SEEP/W) Software | PSM Publishers | Nonprofit Scientific Publishing
Abstract: In this study, SEEP/W was used to develop a finite element model of a non-homogenous earth dam and for this purpose Hub dam was selected. Two different cases i.e. (i) with cut-off wall and (ii) without cut-off wall were studied to check the behaviour of the dam in terms of seepage flux and exit gradient respectively. The software was also used to simulate the phreatic line behaviour for both cases. The outcome of the simulated results showed that the dam is safe against piping, at its original design as the installation of a cut-off wall found working effectively in reducing internal pore water pressure within the dam and its foundation. For case (i), the phreatic line showed a normal trend as it is falling into the filter drain after passing the core with overall minimum seepage flux of order 2.1130 x 10-4 ft3/sec/ft (21.54 LPH) and exit gradient at downstream toe was recorded 0.099 respectively. However, for case (ii) the dam showed an irregular behaviour as the internal