A $1\mathrm{.}4m1\mathrm{.}4m$ footing founded at $1\mathrm{.}5m$ below ground level, supports a load of $890kN$ as

shown below. Calculate the primary consolidation settlement of the $3m$ thick normally

consolidated clay. The clay has an initial void ratio of $0\mathrm{.}99,$ liquid limit of $45\%$ and saturated

unit weight of $18k\frac{N}{m}3.$ The unit weights of the sand above and below the water table are

$16k\frac{N}{m}3$ and $19k\frac{N}{m}3$ respectively.