Example $11\mathrm{.}3$: A soft, normally consolidated clay layer is $18$ m thick. The natural water con$-$

tent is $45\%.$ The saturated unit weight is $18k\frac{N}{m^3}$; the grain specific gravity is $2\mathrm{.}70$ and the

liquid limit is $63\%.$ The vertical stress increment at the centre of the layer due to the founda$-$

tion load is $9k\frac{N}{m^2}.$ The ground water level is at the surface of the clay layer. Determine the

settlement of the foundation.