A concrete hollow box culvert is shown in Figure P14.12. A basement for a building is required near the culvert. One proposal is to construct a sheet pile wall to surround the excavation, as shown in Figure P14.12, and pump out the water in the excavation. The lowest ground water level profile is as shown in Figure P14.12. The equivalent hydraulic conductivity of the soil is 2 × 10-4 cm/s.
(a) Draw the flow net.
(b) Determine the uplift pressure on the box culvert.
(c) Will the culvert be safe against uplift? Assume the frictional resistance per unit length on each side wall
(d) Determine if piping would occur. (Hint: You can calculate the void ratio from the given unit weight.)
