Question $3$

A square Reinforce Concrete pile with a width of $350$ mm is driven through seabed for a jetty structure to carry a maximum compressive load of $500$ kN and a net uplift load of $300$ kN $.$ The soil below seabed consists of a $10$ m thick layer of saturated medium dense sand overlying dense sand and gravel. The average corrected Standard Penetration Test blows in the top $10$ m sand are $12$ and on bottom sand gravel layer is $40.$ No erosion is expected. The minimum safety factor should be $2\mathrm{.}5$ on the uplift load and $4$ on the compressive load. Consider the sketch below.

$3\mathrm{.}1$ Determine the required penetration depth.

$3\mathrm{.}2$ Perform the necessary checks for compression loads.