Answer Happy

A riverbed consists of a layer of sand 8.25 m thick overlying impermeable rock; the depth of water is 2.6 m. A long cofferdam 5.5 m wide is formed by driving two lines of sheet piling to a depth of 6.0 m below the level of the riverbed and excavation to a depth of 2.0 m below pea lever is carried out within the cofferdam. The permeability of sand is 2.65x10-5 m/s. The flow of water into the excavation is: -5.50 m Sheet Sheet piling piling 2.00m 0.90 m Hi 6.00 m ATT 2.25m 4.2x10-5 m³/s P/s per unit length 2.5x10-5 m³/s per unit length 7.3x10-5 m³/s per unit length 8.0x10-5 m³/s per unit length Datum