A shallow foundation of length 8 m and width 3 m is constructed. It exerts a uniform downwards pressure of 300 kPa on the soil beneath it.
(a) Constructing the foundation causes changes in the levels of vertical stress at all points in the soil. One such point lies at the centre of the footing plan, and is at a depth of 10 m. Determine the increment of vertical stress there.
(b) List the assumptions that you needed to make to enable you to answer Part (a). How would you defend your use of them?