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180UB18.1

180UB18.1 Universal Beam

  • AS/NZS 3679.1:2016
  • Design: AS 4100:2020
  • Unverified
Weight Surface area Equivalents XML
Mass18.08kg/m
A2,303mm²
Ix12.13210⁶ mm⁴
Zx138.710³ mm³
180UB18.1 cross-section
Cross-section drawn to scale from nominal dimensions. Cross-hair marks the centroid.

Dimensions

ParameterSymbolValueUnitData
Depthd175.0mmU
Flange widthbf90.0mmU
Flange thicknesstf8.0mmU
Web thicknesstw5.0mmU
Root radiusr18.9mmU

Section Properties

ParameterSymbolValueUnitData
General
Mass per metre mass18.08kg/mC
Gross area A2,303mm²C
About x-axis (major)
Second moment of area Ix Ix12.13210⁶ mm⁴C
Elastic section modulus Zx (min) Zx138.710³ mm³C
Plastic section modulus Sx Sx157.110³ mm³C
Radius of gyration rx rx72.6mmC
About y-axis (minor)
Second moment of area Iy Iy0.97510⁶ mm⁴C
Elastic section modulus Zy (min) Zy21.710³ mm³C
Plastic section modulus Sy Sy33.710³ mm³C
Radius of gyration ry ry20.6mmC
Torsion & warping
Torsion constant JApproximate thin-walled value, fillets neglected J0.03710⁶ mm⁴C
Warping constant IwIy·(d−tf)²/4 Iw6.8010⁹ mm⁶C
Surface area
External surface area extArea0.685m²/mC

Nominal designation mass 18.10 kg/m; calculated 18.08 kg/m (-0.1%).

Steel Grades

GradeStandard fy MPafu MPa NoteData
300 AS/NZS 3679.1:2016 320 440 Typical grade supplied – confirm availability with supplier U

Strengths shown for governing thickness t = 8.0 mm. Density 7850 kg/m³, E = 200 000 MPa.

Where to buy

Producers of Hot-rolled beams & columns (I / H / W) – local mills first. Buy direct from the mill for large tonnages, or through a steel distributor / stockist for small quantities and cut lengths.

Buying checklist
  • Specify the section designation, product standard and steel grade exactly (e.g. "180UB18.1 – AS/NZS 3679.1:2016 – 300").
  • Ask for mill test certificates (EN 10204 type 3.1 or equivalent) traceable to the heat number.
  • Sections from another standard system are not automatically equivalent – have the engineer approve any substitution.
  • Check availability, minimum order quantity, stock lengths, lead time and delivery terms with the mill or distributor.

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Listing is informational only – not an endorsement, offer or confirmation of availability. Company details are marked UNVERIFIED until checked.

Source & Verification

Source publisher
Pending verification – nominal dimensions entered by the application developer
Source document
AS/NZS 3679.1:2016 Structural steel – Hot-rolled bars and sections
Edition
2016
Publication year
2016
Page reference
—
Last updated
2026-10-12
Verification status
Unverified

Nominal dimensions require verification against the current edition of AS/NZS 3679.1:2016 Structural steel – Hot-rolled bars and sections and the manufacturer catalogue before design use. Properties are calculated by this application from the nominal dimensions.

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