250UC149 AS/NZS 3679.1 Grade 300 — Australian Universal Column Section Properties

250UC149 is an Australian UC (Universal Column) per AS/NZS 3679.1 hot-rolled structural steel section. Standard Australian UC dimensions. Verify against Liberty OneSteel / InfraBuild section catalog.

Dimensions (Metric)

Property Value Unit
Depth (d) 260 mm
Flange Width (bf) 255 mm
Flange Thickness (tf) 17.5 mm
Web Thickness (tw) 12.0 mm
Cross-Sectional Area (A) 116.3 cm²
Mass 149.0 kg/m

Elastic Section Properties (Metric)

Property Strong Axis (X-X) Weak Axis (Y-Y) Unit
Moment of Inertia (I) 14,283 4,839 cm⁴
Elastic Section Modulus (S) 1,099 380 cm³
Plastic Section Modulus (Z) 1,234 577 cm³
Radius of Gyration (r) 11.08 6.45 cm

Torsional Properties

Property Value Unit
Torsional Constant (J) 104 cm⁴
Distance Between Flange Centroids (ho) 24.25 cm

Section Profile Summary

This is a standard hot-rolled I-section profile covered by AS 4100. The tabulated section properties are computed from the nominal dimensions per the governing material standard. With Ix = 14,283 cm⁴, the strong-axis flexural stiffness is suitable for preliminary sizing of beams and beam-columns.

At 260 mm deep, this is a mid-range section for secondary beams, roof purlins, and bracing in standard framing.

Key Design Checks (AS 4100)

Check Formula This Section
Plastic moment Mp = Zx × Fy 370 kN·m
Deflection Δ = 5wL⁴/(384EIx) Use Ix = 14,283 cm⁴
Torsion St. Venant = GJ/L J = 104 cm⁴
Column buckling KL/r → Fcr r_x = 11.08 cm

Design Notes

Verification (AS 4100): All designs using this section must be verified by a licensed Professional Engineer. Before finalizing member selection, check beam-column interaction (P-M), lateral-torsional buckling, serviceability deflections, and all connection limit states. See Engineering Disclaimer.

Worked Example: Car park beam — 250uc149

Scenario: Multi-storey car park — asphalt wearing surface included. Simply supported I-section, 5.2 m span, 2.7 m tributary width. Service loads: 6.0 kPa dead + 2.5 kPa live (23.0 kN/m total).

Given:

Step 1 — Live load deflection:

Δ_LL = 5 w_L L⁴ / (384 E Ix)

Δ_LL = 5 × 6.8 × (5200)⁴ / (384 × 200000 × 142,830,000)

Δ_LL = 2.2 mm

Step 2 — Deflection limit (L/300):

Δ_limit = L / 300 = 5200 / 300 = 17.3 mm

Step 3 — Dead + live deflection:

Δ_total = 7.6 mm

Step 4 — Design check:

✓ Live load deflection is within the L/300 limit.

Verify the design moment M*_Ed (from factored loads 1.35G + 1.5Q per AS 4100) does not exceed φMn = 333 kN·m. Also confirm shear resistance and bearing details at the supports.

Related Resources

Design Resources


Educational reference only. Verify all section properties against the current AS 4100 Manual and mill certificates before design. Results are PRELIMINARY — NOT FOR CONSTRUCTION.