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Retaining wall: overturning, sliding and base pressure
Stability of a cantilever retaining wall against overturning and sliding, and the pressures under the base. Reference: IS 456:2000 Cl. 20.1, 20.2.
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# Forces per metre run
W := 260 kN/m
M_r := 520 kN*m/m
P_a := 75 kN/m
M_o := 115 kN*m/m
mu := 0.5
B := 3.0 m
# W is the weight of wall, base and soil on the heel; M_r its moment about the toe.
# Overturning
0.9*M_r >= 1.4*M_o =
FS_o := M_r/M_o =
# Sliding
FS_s := mu*W/P_a =
FS_s >= 1.4 =
# Base pressure
x_r := (M_r - M_o)/W = m
e_b := B/2 - x_r = m
abs(e_b) <= B/6 =
p_max := W/B*(1 + 6*abs(e_b)/B) = kN/m^2
p_min := W/B*(1 - 6*abs(e_b)/B) = kN/m^2How to use this example
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