A bed of sand 12 m thick is underlain by a compressible stratum of normally loaded clay, 6 m thick. The water table is at a depth of 5 m below the ground level. The unit weight of sand above and below water table are 17.5 kN/m3 and 20.5 kN/m3 respectively. The clay has a natural water content of 40% and LL of 45% and Gs=2.75. Estimate the probable final settlement if the average increment in pressure due to foundation is 100 kN/m2

Dry sand; e = 0.55 G, = 2.66 3 m Water table 15 m. Sand G, = 2.66 e = 0.48. 5 m Clay w = 34.78% G, = 2.74 D Rock Figure P2.12 2.13 For a normally consolidated clay layer, given: Thickness 3.7 m Void ratio = 0.82 Liquid limit 42 Average effective stress on the clay layer 110 kN/m2 How much consolidation settlement would the clay undergo if the average effective stress on the clay layer is increased to 155 kN/m2 as the result of the construction of a foundation?

For a clay layer in the field, the following values are given: • Thickness of clay layer = 3 m • Natural Void ratio = 1.65 • Compression index (CC) = 0.28, • Cr = 0.02 • Average effective pressure on the clay layer = 130 kN/m2 •  OCR=1.5   Estimate the increase in settlement caused by an increase in pressure in the layer of 65 kPa.