Determine the safe load that can be carried by a RCC pile having a gross weight of $1\mathrm{.}5t$ using

Modified Hiley's formulae from the following data:

a$.$ Weight of drop hammer $=2t,$ Height of free fall $=91cm,$ Hammer efficiency $=75\%$

b$.$ Average penetration under last five blows $=10mm,$ Length of pile $=22m,$ Dia. of

pile $=300mm,$

c$.$ A well $-$ conditioned driving cap and helmet with hard wood dolly is used for driving.

d$.$ Assume factor of safety as $2\mathrm{.}5.$

$($Ans:$17\mathrm{.}7$ t$)$