W21X275 Steel Beam — Section Properties
Dimensions
| Property | Value | Unit |
|---|---|---|
| Depth (d) | 24.10 | in (612.1 mm) |
| Flange Width (bf) | 12.90 | in (327.7 mm) |
| Flange Thickness (tf) | 2.19 | in |
| Web Thickness (tw) | 1.22 | in |
| Area (A) | 81.80 | in² (527.8 cm²) |
| Weight | 275 | lb/ft (409 kg/m) |
Elastic Section Properties
| Property | Strong Axis (X-X) | Weak Axis (Y-Y) | Unit |
|---|---|---|---|
| Moment of Inertia (I) | 7,690 | 787 | in⁴ |
| Elastic Section Modulus (S) | 638 | 122 | in³ |
| Plastic Section Modulus (Z) | 749 | 191 | in³ |
| Radius of Gyration (r) | 9.70 | 3.10 | in |
Torsional Properties
| Property | Value | Unit |
|---|---|---|
| Torsional Constant (J) | 107 | in⁴ |
| Warping Constant (Cw) | 94,400 | in⁶ |
| Distance Between Flange Centroids (ho) | 21.90 | in |
| Effective Radius (rts) | 3.68 | in |
Design Resources
- Beam Capacity Calculator — Check W21X275 for your span and loads
- Column Capacity Calculator — Check W21X275 as a column
- Section Properties Database — Compare with other sections
- Steel Beam Sizes Reference — Full W-shape dimension table
- Steel Grades Reference — A992/A572 material properties
Frequently Asked Questions
What is the weight of a W21X275 beam? 275 lb/ft (409 kg/m). A 40-ft length weighs approximately 11,000 lbs.
What is the section modulus of W21X275? Sx = 638 in³ (strong axis) and Sy = 122 in³ (weak axis). The plastic section modulus Zx = 749 in³ and Zy = 191 in³.
What steel grade is standard for W21X275? Typically ASTM A992 (Fy = 50 ksi, Fu = 65 ksi) for W-shapes. Also available in A572 Grade 50 or A36. Verify with mill certificate.
What is the moment of inertia of W21X275? Ix = 7690 in⁴ about the strong axis and Iy = 787 in⁴ about the weak axis. The radius of gyration is rx = 9.70 in and ry = 3.10 in.
Related Pages
- Steel Beam Sizes Reference
- Beam Capacity Calculator
- Column Capacity Calculator
- Section Properties Database
Educational reference only. Verify all section properties against the current AISC Manual and mill certificates before design. Results are PRELIMINARY — NOT FOR CONSTRUCTION.