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Combined footing for two columns

Position of the resultant, length and width of a rectangular combined footing with uniform pressure. Reference: IS 456:2000 Cl. 34.

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# Data
P_1 := 700 kN
P_2 := 1000 kN
s := 4 m
a_1 := 0.5 m
q_a := 180 kN/m^2
# a_1 is the projection of the footing beyond the centre of column 1.

# Resultant and size
x_r := P_2*s/(P_1 + P_2) =
L := 2*(a_1 + x_r) =
B := 1.1*(P_1 + P_2)/(q_a*L) = m
B := ceil(B/(0.1 m))*0.1 m = m
q := (P_1 + P_2)/(B*L) = kN/m^2
q <= q_a =

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