Q$2)$ A mat foundation supports eight columns as shown.

a$)$ Calculate the base pressures at point $C$ and $D.$

b$)$ Determine the effective thickness $($d$),$ of the mat assuming the column dimensions are $4040cm$ and $f^{\text{'}}{?}^{\text{'}}=21$MPa.

c$)$ Take strip CD and fined the modified column loads and the modified average soil distribution, using a correction method that you know.

d$)$ If the mat is situated in a $10m$ thick normally consolidated clay deposit, at a depth of $1m,$ as shown below, determine the average consolidation settlement of the clay layer beneath point $D($at the middle of clay layer$).$