For a large fill operation, it was decided to improve $8m$ thick clay layer which is

sandwiched between sand layers by preloading technique. The average permanent

load on the clay layer due to preloading will increase to $85k\frac{N}{m^2}.$ The average

effective overburden pressure on the clay layer before the fill operation is $120k\frac{N}{?}$

$m^2$For the clay layer, which is normally consolidated and drained at top and bottom,

given: $Cc=0\mathrm{.}27,e_0=1\mathrm{.}02,Cv=0\mathrm{.}52\frac{m^2}{?}$ month. Determine the following: $($a$)$ The

primary consolidation settlement of the clay layer caused by the addition of the

permanent load, $($b$)$ The time required for $80\%$ of primary consolidation settlement

under the additional permanent load only and $($c$)$ The temporary surcharge that will

be required to eliminate the entire primary consolidation settlement in $12$ months by

the pre$-$compression technique.