/?/« enjisdJ^J Uyti^ L^ C/lsT') 



ioi^es-i/e. So 



s.// 



b. Cohesionless Soil 



Unit skin friction f^ at any depth is f = K a tan 6 



Assume K (coefficient of lateral earth pressure) = 0.5 



a = effective overburden pressure 



6 = angle of friction between pile and soil 

 (assume 6 = (j) -5**) 



- Pile capacity R = f A 



Average skin friction has been found to peak at pile embedment 

 ~ 20 diameter. 



Recommended value of f, for long piles compiled from Ehlers (1977), 

 Angemeer (1975). 



38 



