Question

Examine the test arrangement and the soil properties given below

${\gamma }_{sat}$ = 18 kN/ $m^3$
$\varphi$ = ${35}^o$
c = 0 kPa
${\gamma }_w$ = 10 kN/$m^3$
$N_{\gamma }$ = 40
Angle of friction, ($\delta$) = ${24}^o$
Earth pressure cofficient, (K) = 1.5

The maximum resistance offered by the soil through skin friction while pulling out pile from the ground is

• A. 104.9 kN
• B. 209.8 kN
• C. 236 kN
• D. 472 kN

Answer 1

The correct option is A 104.9 kN


Diameter of pile = 0.5 m
Angle of friction, $\delta ={24}^o$
Earth pressure coefficient,
k = 1.5
Max. resistance = Average frictional stress $\times$ Area

$=\frac{1}{2}{\sigma }_H\times tan\delta \times A$

$=\frac{1}{2}k{\sigma }_V\times A\times tan\delta$

$=\frac{1}{2}\times k\times {\gamma }_{sub}\times 5\times \pi DL\times tan\delta$

$=\frac{1}{2}\times 1.5\times 8\times 5\times \pi \times 0.5\times 5\times tan\left({24}^o\right)$

= 104.9 kN