A square footing 3 m by 3 m supports a building column load that results in a foundation bearing pressure of 200 kPa. The deep sand stratum underlying the foundation has an average unit weight of 17.0 kN/m3 and is classified as medium-dense. Use the subgrade reaction method to estimate the foundation settlement.

For the square footing (1.5mx1.5m) shown in Figure (Q5), Find the total settlement (elastic and consolidation) at the center of the foundation. Use the approximate method to compute the stress increase. EST 3.5m was Figure (Q5) 1000 kN 1.5m 1.5m Y-18 kN/m² Year 19 kN/m² E, -40 MPa P. - 0.25 You 20 kN/m² Yw= 10 kN/m' E, -50 MPa, μ, 0.3 C = 0.3, C, = 0.04 -90 kN/m², e. - 0.8 Rock

* 3 m b. Is the clay overconsolidated? c. What would be the consolidation settlement beneath the center of the mat? 6m A 15 m X 20 m mat foundation shown in Figure P10.7 car- ries a building load of 36 MN and is placed at 3.0 m depth below the ground level. 5 m For the clay layer, the consolidation tests show that the preconsolidation pressure at the middle of the clay layer is 210 kN/m². a. Find the net applied pressure on the underlying ground. Q Sand Clay y = 16.5 kN/m³ Ysat 19.0 kN/m³ e = 0.82 Ce=0.35 and C, = 0.06 =

4. A square foundation will be constructed at ground surface. The subsoil profile is shown in the figure below. The mat will have a net uniform load of 500 psf at El. O. The mat will have a net uniform load (Induce stress) at El. -15 of 360 psf, the primary consolidation settlement (in.) of the clay layer directly below the center of the foudnation is? fr ORIGINAL GROUND SURFACE ELEV. O ft ELEV-5 ft. ELEV-10 ft ELEV-20 ft 30 ft SAND Y = 115 pcf MAT FOUNDATION SAND Y = 105 pcf GROUNDWATER TABLE NORMALLY CONSOLIDATED CLAY SATURATED UNIT WEIGHT = 95 pcf COMPRESSION INDEX C₂ = 0.29 VOID RATIO=1.0