Numerical problem , single ,group pile capacity 1 (usefulsearch.org) (useful search)

1. Sol.
Weight of hammer, W = 4 tons = 40KN
Height of hammer, H = 90cm.
Final set penetration/ blows , S = 5mm = 0.5cm
Empirical constant, C = 2.5cm (for drop hammer)
Assumimg factor of safety, F = 6
Therefore, from Engineering News Formula, allowable load
carrying capacity, Qa
Qa = WH/ F(S+C)
= 40*90/6( 0.5+ 2.5)
= 200KN/m^2
Ans. Load carrying capacity of pile is 200KN/m^2

2. Sol.
Pile sectional area, A = 50cm*50cm
=0.5m*0.5m
Length of pile, h = 10m
Cohesion , C = 40KN/m^2
Adhesion factor, m = 0.7
load carrying capacity due to skin friction , Qup
Qup = As.Rf
= 2*h*(l+b)*(C*m)
= 2*10*(0.5+0.5) * (40*0.7)
= 560KN/m^2
Ans. Load carrying capacity due to skin friction is
560KN/m^2.

3. Sol.
load carried by pile, P= 3000KN
depth of clay bed, D = 20m
unconfined compressive strength, qu = 0.7kg/cm^2
= 70KN/m^2
therefore, Cohesion, C = qu/2 = 70/2 = 35KN/m^2
adhesion factor, m= 0.4
liquid limit, LL = 0.60
factor of safety, F= 3
diameter of pile, d = 0.6m
height of pile, h = 14m