Question $6$:

$($Value: $\backslash (\backslash$mathbf$\{24\}\backslash )$ marks$)$

It is proposed to carry the load from a $5$ story structure with an area of $\backslash (600\backslash$mathrm$\{$~m$\}^\{2\}\backslash )$ in sand using $25$ square column footings. The standard penetration test results obtained from field exploration are summarized below. $($i$.$e$.,$ corrected $\backslash (\backslash$mathrm$\{$N$\}\_\{60\}\backslash )$ results versus depth$).$ The depth of foundation was proposed to be at $1\mathrm{.}5$ m and the tolerable settlement is $15$ mm $.$ Using a suitable empirical design method determine the size of the foundation. $($Hint: Assume a load of $10$ kPa per story$)$

Also, determine the bearing capacity of this foundation using Terzaghi's bearing capacity equation, if the GWT is at the natural ground level. Assume $\backslash (\backslash$gamma$\_\{\backslash$text $\{$sat $\}\}=20\backslash$mathrm$\{$kN$\}/\backslash$mathrm$\{$m$\}^\{3\}\backslash ).$

What are the comments that you would offer to the owner as a consultant for this foundation?

Note: If you need any additional information for solving this problem, make suitable assumptions providing justification$).$