Uplift pressures at points E and D (Figure A) of a straight

Uplift pressures at points E and D (Figure A) of a straight horizontal floor of negligible thickness with a sheet pile at downstream end are 28% and 20%, respectively. If the sheet pile is at upstream end of the floor (Figure B), the uplift pressures at points D₁ and C₁ are

1. 68% and 60% respectively
2. 80% and 72% respectively
3. 88% and 70% respectively
4. 100% and zero respectively

A + D₁
Uplift pressure = 100 – (head loss along DC)
= 100 – 20 = 80%
A + C₁ Uplift pressure = 100 – (head com from E to C)
= 100 – 28 = 72%