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Punching shear of a flat slab at an interior column

Critical perimeter at d/2 from the column face, shear stress and the permissible punching shear stress. Reference: IS 456:2000 Cl. 31.6.1-31.6.3.

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# Data
c_1 := 500 mm
c_2 := 400 mm
d := 220 mm
f_ck := 25 MPa
V_u := 700 kN

# Critical section
b_0 := 2*(c_1 + d + c_2 + d) = mm
tau_v := V_u/(b_0*d) = MPa

# Permissible stress
beta_c := min(c_1, c_2)/max(c_1, c_2) =
k_s := min(0.5 + beta_c, 1) =
tau_c := k_s*0.25*sqrt(f_ck/(1 MPa))*1 MPa =
tau_v <= tau_c =

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