ESE 2021 Technical Quiz || Seepage Analysis

The water seeping below the body of the hydraulic structure, endangers the stability of the structure by
i. Undermining
ii. Piping
iii. Direct uplift
iv. Heaving action
Which of the above cause failure of the structure?

The portion between two successive flow lines in a flow net is referred as

A flow net can be used for which of the following purposes?

A 12.5m thick clay is underlain by sand. When the depth of an open trench excavated in the clay reached a depth of 8m, the bottom cracked and the water started entering the trench from below. Considering the saturated unit weight of clay as 18.5 kN/m³ and unit weight of water as 10 kN/m³, the height below the top of clay upto which water would have risen in a bore hole if it were drilled into prior to the excavation as