What Is Seepage ,Seepage Pressure , ?? Soil Mechanics
SEEPAGE * Seepage is the movement of water through the soil under hydraulic gradient. * The pressure that is exerted on the soil due to the seepage of water is called the seepage force or seepage pressure. * The problems posed by seepage are: 1. Loss of stored water by an earth dam 2. Settlement of water retaining structures resting on soil due to consolidation of soil underneath. 3. Uplift pressure on hydraulic structures exerted by percolating water. 4. Instability of soil bunds. * If flow occurs in the downward direction, the effective pressure is increased. If flow occurs in the upward direction effective pressure is decreased. * If the seepage pressure becomes equal to the submerged weight of the soil, the effective pressure reduces to zero. At this stage, the cohesionless soil losses its shear strength completely and its particles have tendency to move up in the direction of flow. This phenomenon is known as quick condition or quick sand. The hydraulic gradient at which quick con...