W920x449 G40.21 350W — Canadian W-Shape Section Properties
Approximate equivalent of W36X302 per AISC A6. Approx. equivalent of W36X302. Verify against CISC Handbook.
Dimensions (Metric)
| Property | Value | Unit |
|---|---|---|
| Depth (d) | 947.4 | mm |
| Flange Width (bf) | 424.2 | mm |
| Flange Thickness (tf) | 42.7 | mm |
| Web Thickness (tw) | 24.0 | mm |
| Cross-Sectional Area (A) | 574.2 | cmÃÂò |
| Mass | 449.4 | kg/m |
Elastic Section Properties (Metric)
| Property | Strong Axis (X-X) | Weak Axis (Y-Y) | Unit |
|---|---|---|---|
| Moment of Inertia (I) | 878,245 | 54,110 | cm⁴ |
| Elastic Section Modulus (S) | 18,517 | 2,556 | cmÃÂó |
| Plastic Section Modulus (Z) | 20,975 | 3,949 | cmÃÂó |
| Radius of Gyration (r) | 39.12 | 9.70 | cm |
Torsional Properties
| Property | Value | Unit |
|---|---|---|
| Torsional Constant (J) | 2,676 | cm⁴ |
| Warping Constant (Cw) | 110,622,000 | cm⁶ |
| Distance Between Flange Centroids (ho) | 90.42 | cm |
| Effective Radius (rts) | 11.51 | cm |
Imperial Reference
| Property | Value | Unit |
|---|---|---|
| Depth (d) | 37.30 | in |
| Flange Width (bf) | 16.70 | in |
| Area (A) | 89.00 | inÃÂò |
| Weight | 302 | lb/ft |
Section Profile Summary
A wide flange with parallel flange faces — makes bolted and welded connections straightforward to detail. At Ix = 878,245 cm⁴, the strong-axis stiffness places it in the heavy beam category for preliminary sizing.
At 947.4 mm deep and 449.4 kg/m, this is a heavy section for primary framing — transfer beams, long-span roof girders, and major bridge stringers.
Key Design Checks (CSA S16)
| Check | Formula | This Section |
|---|---|---|
| Plastic moment | Mp = Zx × Fy | 7,341 kNÃÂ÷m |
| Deflection | Δ = 5wL⁴/(384EIx) | Use Ix = 878,245 cm⁴ |
| Torsion | St. Venant = GJ/L | J = 2,676 cm⁴ |
| Column buckling | KL/r → Fcr | r_x = 39.12 cm |
Design Notes
- Compactness: Most W-shapes in ASTM A992 satisfy the compact limits in CSA S16 Table B4.1b for flexure (λ ≤ λp). This allows full plastic moment Mp development before local buckling occurs.
- Flange local buckling (FLB): The flange slenderness ratio bf/2tf is compared against λpf = 0.38√(E/Fy) ≈ 9.0 for compact sections.
- Web local buckling (WLB): h/tw is checked against λpw = 3.76√(E/Fy) ≈ 72 for flexure, and a more restrictive limit for uniform compression.
- Lateral-torsional buckling (LTB): Lp ≈ 408.1 cm (plastic limit). For unbraced lengths ≤ Lp, the full plastic moment is available. Between Lp and Lr, linear interpolation per CSA S16 Eq. F2-2 applies.
Verification (CSA S16): 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: Residential floor beam — w920x449
Scenario: Residential apartment floor — partition allowance included in dead load. Simply supported wide flange, 17.1 m span, 3 m tributary width. Service loads: 3.0 kPa dead + 2.0 kPa live (15.0 kN/m total).
Given:
- Span L = 17053 mm (17.1 m)
- Total service load w = 15.0 kN/m
- Live load portion w_L = 6.0 kN/m
- Section w920x449: Ix = 8782.5 × 10⁶ mm⁴, Sx = 18,517,000 mm³, Zx = 20,975,000 mm³
- Steel: fy = 350 MPa, E = 200,000 MPa
- Design moment resistance: φMn = 0.9 × Zx × fy = 6,607 kNÃÂ÷m
Step 1 — Live load deflection:
Δ_LL = 5 w_L L⁴ / (384 E Ix)
Δ_LL = 5 × 6.0 × (17053)⁴ / (384 × 200000 × 8,782,450,000)
Δ_LL = 3.8 mm
Step 2 — Deflection limit (L/360):
Δ_limit = L / 360 = 17053 / 360 = 47.4 mm
Step 3 — Dead + live deflection:
Δ_total = 9.4 mm
Step 4 — Design check:
✓ Live load deflection is within the L/360 limit.
Verify the design moment M*_Ed (from factored loads 1.35G + 1.5Q per CSA S16) does not exceed φMn = 6,607 kNÃÂ÷m. Also confirm shear resistance and bearing details at the supports.
Related Resources
- Steel Beam Capacity Calculator
- Column Capacity Calculator
- Beam Deflection Calculator
- Section Properties Calculator
- Steel Grades Reference
- Section Comparison Tool
Design Resources
- Section Properties Lookup — Compare with similar sections
- Steel Beam Sizes Reference — Standard beam dimensions
Educational reference only. Verify all section properties against the current CSA S16 Manual and mill certificates before design. Results are PRELIMINARY — NOT FOR CONSTRUCTION.