The steel section 180×18.1 UB falls under the section category of Universal Beams. The section 180×18.1 UB is denoted by the Standard Industry section notation – 180UB18.1. In Australia and New Zealand, the nominal section dimensions and weights of hot-rolled sections are defined in Appendix D of AS/NZS 3679.1:2016 Structural Steel – Hot-Rolled Bars and Sections. These dimensions are used to calculate the design section properties of this section.
Summary of Geometrical and Sectional Properties of 180×18.1 UB
Section properties of 180UB18.1 in metric units and imperial units (US Customary Units) are summarised in the table below
|Property Component||Metric Units||Imperial Units (US Units)|
|Depth of section, d||17.50 cm||6.89 in|
|Breadth of section or Flange width, b||9.00 cm||3.54 in|
|Flange thickness, tf||0.80 cm||0.31 in|
|Web thickness, tw||0.50 cm||0.20 in|
|Root radius, r||0.89 cm||0.35 in|
|Total Area of section, A||23.03 cm2||3.57 in2|
|Second moment of area about x-axis, Ixx||1213.00 cm4||29.14 in4|
|Second moment of area about y-axis, Iyy||97.52 cm4||2.34 in4|
|Radius of gyration about x-axis, rx||7.26 cm||2.86 in|
|Radius of gyration about y-axis, ry||2.06 cm||0.81 in|
|Elastic section modulus about x-axis, Zxx||138.60 cm3||8.46 in3|
|Elastic section modulus about y-axis, Zyy||21.67 cm3||1.32 in3|
|Plastic section modulus about x-axis, Sxx||157.10 cm3||9.59 in3|
|Plastic section modulus about y-axis, Syy||33.70 cm3||2.06 in3|
|Warping Constant, Iw||6799.00 cm6||25.32 in6|
|Torsional Constant, J||4.48 cm4||0.11 in4|
|Mass of section, M||18.08 kg/m||12.15 lb/ft|
Summary of Geometrical and Sectional Properties of 180×18.1 UB in millimetres, mm
Section properties of 180UB18.1 in millimeters, mm are summarised in the table below
|Property Component||Metric Units|
|Depth of section, d||175.00 mm|
|Breadth of section or Flange width, b||90.00 mm|
|Flange thickness, tf||8.00 mm|
|Web thickness, tw||5.00 mm|
|Root radius, r||8.90 mm|
|Total Area of section, A||2303.00 mm2|
|Second moment of area about x-axis, Ixx||12130000.00 mm4|
|Second moment of area about y-axis, Iyy||975200.00 mm4|
|Radius of gyration about x-axis, rx||7.26 cm|
|Radius of gyration about y-axis, ry||20.58 mm|
|Elastic section modulus about x-axis, Zxx||138600.00 mm3|
|Elastic section modulus about y-axis, Zyy||21670.00 mm3|
|Plastic section modulus about x-axis, Sxx||157100.00 mm3|
|Plastic section modulus about y-axis, Syy||33700.00 mm3|
|Warping Constant, Iw||6799000000.00 mm6|
|Torsional Constant, J||44760.00 mm4|
|Mass of section, M||18.08 gm/mm|
Geometry of 180×18.1 UB in mm – SI units
Total depth of section = Section depth, d = 175.00 mm
Total breadth of section = Section width, b = 90.00 mm
Flange thickness, tf = 8.00 mm
Web thickness, tw = 5.00 mm
Root radius, r = 8.90 mm
Total Area of section, A = 2303.00 mm2
Mass of section, M = 18.08 kg/m
Sectional Properties of 180×18.1 UB in mm – Metric units
The Second Moment of Area or Second Area Moment or Quadratic Moment of Area or Area Moment of Inertia or moment of Inertia about x-axis, Ixx = 12130000.00 mm4
The Second Moment of Area or Second Area Moment or Quadratic Moment of Area or Area Moment of Inertia or moment of Inertia about y-axis, Iyy = 975200.00 mm4
Radius of gyration about x-axis, rx = 72.58 mm
Radius of gyration about y-axis, ry = 20.58 mm
Elastic section modulus about x-axis, Zxx = 138600.00 mm3
Elastic section modulus about y-axis, Zyy = 21670.00 mm3
Plastic section modulus about x-axis, Sxx = 157100.00 mm3
Plastic section modulus about y-axis, Syy = 33700.00 mm3
Warping Constant, Iw = 6799000000.00 mm6
Torsional Constant, J = 44760.00 mm4
Structural Design Parameters of 180×18.1 UB or 180UB18.1 in mm – Metric units
Based on the design application and structure type, Universal Beams are to be designed in accordance with AS-NZS 5100.6-2017 and AS 4100:2020. Another design guide available for designers is AISC – Design of Structural Connection 4th Edition 1994 published by Australian Steel Institute.
Depth of web between flanges, dw = 159.00 mm
Surface area = 0.68 m2/m
Ratio of outstanding flange/thickness of flange = 5.625
Web slenderness ratio or ratio of clear web depth/thickness of web = 31.800
Buckling Parameter of section = 0.885
Trivia – Hot-rolled Universal Beam Structural Steel Sections
Grade 300 Steel is the most common and standard grade manufactured by most manufacturers in Australia for hot rolled Structural Steel Sections. Depending on project and client demands, other grades available in the market are 300L0, 300L15, 350, 350L0 & 350L15.
Common stock lengths available in the market are 9.0m, 10.5m, 12.0m, 13.5m, 15.0m, 16.5m, 18.0m & 20.0. However, some lengths may not be available depending on the supplier.
Hot-rolled Structural Steel Sections are usually supplied in Mill Finish. Although, other finishes are available on demand or special orders.
Universal Beams are available in section depths of 150mm, 180mm, 200mm, 250mm, 310mm, 360mm, 410mm, 460mm, 530mm & 610mm.
FAQs on 180×18.1 UB or 180UB18.1
An indicative cost of cutting 180UB18.1 beam in Australia is $18/cut. However, the final rates will depend largely on volume of order and tools used.
In Australia, the retail selling rate of 180UB18.1 is $83 per linear metre for raw/mill finish and $94 per linear metre for primed finish, excluding GST and volume discounts.
Suppliers can charge up to $3 per hole for drilling in hot rolled beams in Australia.
The weight of 180UB18.1 per meter is 18.08 kg/m
The cross-sectional area of 180UB18.1 is 2303.00 mm2
The exposed surface area of 180UB18.1 per meter is 0.68 m2/m
Data on this page has been verified and validated with multiple data sources and reviewed regularly for correctness and accuracy, if you have any comments or suggestions, please reach out to us here.