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Axial capacity of a bored pile in clay (alpha method)

Shaft friction by the alpha method, end bearing with Nc = 9 and the allowable load of a bored pile in clay. Reference: Alpha (total stress) method; EN 1997-1 7.6.

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# Pile and soil
D_p := 0.6 m
L_p := 15 m
c_u := 50 kPa
c_ub := 80 kPa
alpha_s := 0.5
F_s := 2.5

# Shaft
A_s := pi*D_p*L_p = m^2
Q_s := alpha_s*c_u*A_s = kN

# Base
A_b := pi*D_p^2/4 = m^2
Q_b := 9*c_ub*A_b = kN

# Capacity
Q_ult := Q_s + Q_b = kN
Q_allow := Q_ult/F_s = kN

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