Steel · Fire, corrosion & serviceability

Deflection limits checker calculator

Maximum deflection of simply supported, propped, fixed or cantilever members under UDL and point load, against selectable limits.

Standard: AS/NZS 1170.0 Appendix C (typical limits)

Inputs in the worked example

The live calculator starts with these values; change any of them and every result, check and diagram updates instantly.

Diagram for the worked example

UDL coefficient = CHOOSE(1,5/384,1/185,1/384,1/8) = 0.013021
Point load coefficient = CHOOSE(1,1/48,1/107.3,1/192,1/3) = 0.020833
Deflection = (0.013021*8*(6*1000)^4+0.020833*0*1000*(6*1000)^3)/(2.000e+5*1.420e+8) = 4.7535 mm
Limit = 6*1000/250 = 24 mm

Fire: limiting steel temperature — Limiting temperature from the load ratio, yield stress and modulus reduction factors at a given temperature…
Corrosion allowance & coating life — First-year corrosion rate by category, long-term thickness loss per side with the ISO 9224 power law…
Floor vibration from walking (AISC Design Guide 11) — Natural frequency from the deflection of the floor system under its in-service weight, the predicted peak…
Steel beam (UB) — Section and member moment capacity (lateral-torsional buckling), shear and deflection, with built-in UB sizes.
Steel angle lintel — Equal-angle lintel over a masonry opening with triangular (arching) or full masonry load.
Steel I-beam in torsion with warping — UB or UC simply supported with fork ends (twist prevented, warping free) carrying an eccentric point load at…

For preliminary design and education. Check every result against the current standard and your own engineering judgement before use.