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Retaining wall: active earth pressure

Rankine active pressure coefficient, total thrust and overturning moment on a cantilever retaining wall. Reference: IS 456:2000 Cl. 20 (loads from soil mechanics).

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Retaining wall: active earth pressure: worked example sheet in Equation Pad with typeset equations and results.

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# Data
H := 4.5 m
gamma_s := 18 kN/m^3
phi_s := 30 deg
q_s := 10 kN/m^2

# Pressure
k_a := (1 - sin(phi_s))/(1 + sin(phi_s)) =
P_a := k_a*gamma_s*H^2/2 = kN/m
P_q := k_a*q_s*H = kN/m
M_o := P_a*H/3 + P_q*H/2 = kN*m/m

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