Uplift Pressure Head

Q. Uplift pressures at points E and D (Fig. A) of a straight horizontal floor of negligible thickness with a sheet pile at the downstream end are 28% and 20% respectively. If the sheet pile is at the upstream end of the floor (Fig B), the uplift pressures at points $D_{1}and{C}_1$ are

1. 35% and 60% respectively
2. 80% and 72% respectively
3. 88% and 70% respectively
4. 100% and zero respectively

Q. The profile of a weir on the permeable foundation is shown in figure I and an elementary profile 'upstream pile only case' according to Khosla's theory is shown in figure II. The uplift pressure heads at key points Q, R, and S are 3.14 m, 2.75 m, and 0 m, respectively (refer figure II).


What is the uplift pressure head at point P downstream of the weir (junction of floor and pile as shown in the figure I)?

1. 2.75 m
2. 1.25 m
3. 0.8 m
4. Data not sufficient

Q. Uplift pressures at points A and B shown in figure are 1.575 and 2.420 m respectively. If the sheet pile is at the downstream end of the floor, the uplift pressure at C is ________ m.

1. 1.425