A river bed consists of a layer of sand 8.25 m thick overlying impermeable rock; the depth of water is 2.50 m. A long cofferdam 5.50 m wide is formed by driving two lines of sheet piling to a depth of 6.00 m below the level of the river bed and excavation to a depth of 2.00 m below bed level is carried out within the cofferdam  The water level within the cofferdam is kept at excavation level by pumpi

Q: 4. A lake with a water depth of 12m in underlain by a soil with a saturated unit weight of 18.2…

A:

Calculation of Settlement

The vertical displacement of the structural foundation due to the loading from the superstructure is known as settlement. It is due to the reduction of air voids present in the soil. The amount of vertical displacement depends on the bearing capacity of the soil on which the foundation is laid. The effect of the settlement depends on the magnitude of settlement, uniformity, and the structural design of the structure. The maximum allowable settlement for residential and office buildings should be less than 18 mm, for industrial buildings, it is 38 mm and for commercial buildings, it is 25 mm.