$11\mathrm{.}3$ A shallow foundation supported by a silty sand is shown in Figure $11\mathrm{.}6.$ Given:

Length: $L=3m$

Width: $B=3m$

Depth of foundation: $D_f=1\mathrm{.}5m$

Thickness of foundation: $t=0\mathrm{.}25m$

Load per unit area:

$=150k\frac{N}{m^2}$

$E_f=15{10}^{6}k\frac{N}{m^2}$

The silty sand has the following properties.

$H^{\text{'}}=20m$

${}_s=0\mathrm{.}3$

$E_O=16,000k\frac{N}{m^2}$

$k=400k\frac{N}{m^2}\frac{?}{m}$

Using Eq$.(11\mathrm{.}20),$ estimate the elastic settlement of the foundation.

$S_e=\frac{B_e{I}_G{I}_F{I}_E}{E_O}(1-{}_s^2)$