Determine the size of a square footing at the ground level to transmit a load of 900 kN in sand weighing 18 kN/m3 and having an angle of shearing resistance of 36° (Nγ = 46, Nq = 43). Factor of safety is 3.

What will be the modification in the result, if the footing may be placed at a depth of 1 m below ground surface ? Assume, in this case, the water table may rise to the ground surface. γ′ = 9 kN/m3