$13\mathrm{.}3$ A static pile load test using an O$-$cell was carried out on a $1\mathrm{.}8-m-$diameter, $25-$m$-$long $($embedded length$)$ drilled shaft. The soil profile is as given in Table P$13\mathrm{.}3$a $($the negative sign means below ground surface$).$ Selected load$-$displacement data are shown in Table P$13\mathrm{.}3$b$.($a$)$ Make a neat sketch of the soil profile and the drilled shaft, as shown in Example $13\mathrm{.}3.($b$)$ Determine the ultimate skin friction and ultimate end bearing capacity. $($c$)$ If an FS of $2$ is required, determine the allowable load and settlement. Justify your answers.

TABLE P$13\mathrm{.}3$a

$\backslash$table$[[$Elevation $($m$),5$ to $-3\mathrm{.}4,-3\mathrm{.}4$ to $-17\mathrm{.}6,-17\mathrm{.}6$ to $-38\mathrm{.}2],[$Soil type,$\backslash$table$[[$Sandy fat$],[$clay $($CH$)]],\backslash$table$[[$Silty sand with$],[$gravel $($SM$)]],\backslash$table$[[$Mudstone or$],[$weak rock$]]]]$

TABLE P$13\mathrm{.}3$b

$\backslash$table$[[$Load $($MN$),0,1,5,8,10,15,20,25,27,27\mathrm{.}2,27\mathrm{.}1,0],[\backslash$table$[[$Displacement$],[$up $($mm$)]],0,0\mathrm{.}4,0\mathrm{.}8,1,1\mathrm{.}2,1\mathrm{.}5,3\mathrm{.}4,6\mathrm{.}5,8,9\mathrm{.}2,10\mathrm{.}8,9\mathrm{.}0],[\backslash$table$[[$Displacement$],[$down $($mm$)]],0,-0\mathrm{.}5,-6,-10,-11,-16,-21,-29,-43,-40,-41,-37]]$