Problem $2$: A site is prepared for construction by adding $1$ m of sand and gravel fill, in a section of the site a $3$ m square footing is installed and applies a load of $450$ kN to the soil below. Assume that the fill and footing are placed at the same time. Perform calculations by dividing the clay layer into $2$ sublayers and estimate the ultimate settlement of the footing due to the combined load of the fill and the footing.

Estimate the settlement of the footing with the $2$:$1$ method.