کلیدواژهها
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Cutoff wall, Hydraulic gradient, non-isotropic foundation, Sabalan rockfill dam,
Seepage
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چکیده
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One of the important issues in soil dam design construction is controlling seepage from the body
and foundation of the dam for stability secure and prevention of piping and water loss. The seepage
through the foundation of earth dams can be controlled using cut-off walls. this study investigates
the efficiency of the cutoff wall on some design parameters in the Sabalan rockfill dam. For this
purpose, different positions of cutoff walls with various depth and permeability were used in the
non-isotropic foundation of the dam. The results showed that the maximum hydraulic gradient in
the foundation of the Sabalan dam occurs at the cutoff wall. Change in cut-off wall position for
obtaining minimum hydraulic gradient showed that the optimal position of the cut-off wall for
reducing the hydraulic gradient is in the toe of the core and the optimal position of cut-off the wall
for reducing the seepage is in the heel of the core. By reducing the permeability and increasing the
depth of the cutoff wall, the hydraulic gradient is increased and the seepage is decreased.
Comparison of the effect of permeability and depth of the cutoff
wall on seepage with
corresponding values in Karkheh embankment dam, showed proper agreement between them.
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