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Depth of a beam from the limiting moment

Minimum effective depth for a balanced section and the overall depth to use. Reference: IS 456:2000 Annex G.

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Depth of a beam from the limiting moment: worked example sheet in Equation Pad with typeset equations and results.

Example only. This sheet shows one way to set out the check. It is not endorsed by the bodies that publish the design codes and does not reproduce them. Check every clause, value and assumption against your own copy of the current edition of IS 456 before you use it, and have the result checked by a competent person. See the disclaimer.

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# Data
M_u := 185 kN*m
b := 300 mm
f_ck := 25 MPa

# Depth
d_min := sqrt(M_u/(0.138*f_ck*b)) = mm
D := ceil((d_min + 50 mm)/(25 mm))*25 mm = mm

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More IS 456 sheets on beams

The same topic in Eurocode 2