11.1 A vertical column load, P = 600 kN, is applied to a rigid concrete foundation with dimensions B = 1 m and L = 2 m, as shown in Figure 11.45. The founda- tion rests at a depth D₁ = 0.75 m on a uniform dense sand with the following properties: average modulus of elasticity, E¸ 20,600 kN/m², and Poisson's ratio, μ = 0.3. Estimate the elastic settlement due to the net applied pressure, Ao, on the foundation. Given: H = 5 m. Foundation BXL Figure 11.45 600 KN V 74 Ao Soil Ms = 0.3 Es = 20, 600 kN/m² Rock = 0.75 m 5.0 m

A rigid foundation is subjected to a vertical column load, P = 355 kN, as shown in Figure 11.43. Estimate the elastic settlement due to the net applied pressure, Ao, on the foundation. Given: B = 2 m; L = 3 m; D, = 1.5 m; H = 4 m; E, = 13,500 kN/m²; and µ, = 0.4. Foundation Δσ D BX L Soil Poisson's ratio E, = modulus of elasticity H %3D Rock O Cengage Leaming 2014

A circular foundation (D = 6 m) is built on a construction site where the soil profile is shown in Figure 5 below. The circular foundation applies a uniform pressure of 80 kPa to the surface of clay. The properties of the clay are: Specific gravity, G₁ Saturated unit weight at Compression index Ce Recompression index Cr Consolidation coefficient, c Over-consolidation ratio, OCR 10 m 6m Ø Clay Impervious rock Figure 5 2.6 20 kN/m³ 0.25 0.10 2.5 m²/year 1.2 (b) Calculate the stress increase at the center of the clay layer and 1) beneath the foundation center and 2) beneath the edge of the foundation; (c) Calculate the consolidation settlement beneath the center of the foundation due to the stress increase; (d) Determine the settlement at the center of the clay after 1 year of applying the pressure; (e) A 50 mm thick clay sample was taken from the site and consolidated in the oedometer, how long it will take for the clay to reach 90% consolidation?