W24×207 Steel Beam
A W24×207 is a wide flange steel beam 25.7 inches deep with 13-inch flanges, weighing 207 pounds per foot. In ASTM A992 steel (Fy = 50 ksi) it has a design bending strength of 2,273 kip-ft (LRFD) when its compression flange is braced, and a design shear strength of 671 kips.
Design a W24×207 beam Opens a 39 ft span in the free beam designer.
W24×207 dimensions
| Dimension | Value |
|---|---|
| Depth, d | 25.7 in |
| Flange width, bf | 13.0 in |
| Flange thickness, tf | 1.57 in |
| Web thickness, tw | 0.870 in |
| Distance to web toe of fillet, kdes | 2.07 in |
| Distance between flange centroids, ho | 24.13 in |
| Cross-sectional area, A | 60.7 in2 |
| Weight | 207 lb/ft |
Dimensions are AISC design values. Detailing dimensions are rounded to the nearest 1/16 in.
W24×207 section properties
| Property | Strong axis (x) | Weak axis (y) |
|---|---|---|
| Moment of inertia, I | 6820 in4 | 578 in4 |
| Elastic section modulus, S | 531 in3 | 88.8 in3 |
| Plastic section modulus, Z | 606 in3 | 137 in3 |
| Radius of gyration, r | 10.6 in | 3.08 in |
| Torsion and slenderness | Value |
|---|---|
| Torsional constant, J | 38.3 in4 |
| Warping constant, Cw | 84100 in6 |
| Effective radius of gyration, rts | 3.62 in |
| Flange slenderness, bf/2tf | 4.14 |
| Web slenderness, h/tw | 24.8 |
W24×207 bending and shear strength
For ASTM A992 steel (Fy = 50 ksi, E = 29,000 ksi) per AISC 360-16. Its flanges and web are compact for bending, so with its compression flange braced it reaches its full plastic moment.
| Strength | LRFD | ASD |
|---|---|---|
| Bending, compression flange braced | φMn = 2,273 kip-ft | Mn/Ω = 1,512 kip-ft |
| Shear | φVn = 671 kips | Vn/Ω = 447 kips |
If the compression flange isn't braced, the beam can buckle sideways before it yields. Up to Lp = 10.9 ft between braces it keeps its full strength; past Lr = 41.8 ft it buckles elastically. With uniform moment between braces (Cb = 1.0):
| Unbraced length, Lb | φMn (LRFD) | Mn/Ω (ASD) |
|---|---|---|
| Braced | 2,273 kip-ft | 1,512 kip-ft |
| 10 ft | 2,273 kip-ft | 1,512 kip-ft |
| 10.9 ft (Lp) | 2,272 kip-ft | 1,512 kip-ft |
| 20 ft | 2,013 kip-ft | 1,339 kip-ft |
| 30 ft | 1,728 kip-ft | 1,150 kip-ft |
| 40 ft | 1,444 kip-ft | 961 kip-ft |
| 41.8 ft (Lr) | 1,394 kip-ft | 927 kip-ft |
| 50 ft | 1,130 kip-ft | 752 kip-ft |
| 60 ft | 922 kip-ft | 614 kip-ft |
| 70 ft | 780 kip-ft | 519 kip-ft |
| 80 ft | 677 kip-ft | 450 kip-ft |
A beam with a uniform load between braces has Cb above 1.0 (1.14 for a simple span braced only at its ends), so these values are conservative. The beam designer works out Cb for every segment between braces.
W24×207 load table by span
The largest uniform load a simply supported W24×207 can carry, in kips per foot, with its compression flange braced along its length (by a floor or roof deck, for example). The loads include the beam's own weight of 0.207 kips per foot.
| Span | Factored load (LRFD) | Allowable load (ASD) | Load at span/360 | Load at span/240 |
|---|---|---|---|---|
| 13 ft | 103.2* | 68.8* | 133.4 | 200.1 |
| 15 ft | 80.8 | 53.8 | 86.8 | 130.2 |
| 17 ft | 62.9 | 41.9 | 59.6 | 89.5 |
| 19 ft | 50.4 | 33.5 | 42.7 | 64.1 |
| 21 ft | 41.2 | 27.4 | 31.6 | 47.5 |
| 23 ft | 34.4 | 22.9 | 24.1 | 36.1 |
| 25 ft | 29.1 | 19.4 | 18.8 | 28.1 |
| 27 ft | 24.9 | 16.6 | 14.9 | 22.3 |
| 29 ft | 21.6 | 14.4 | 12.0 | 18.0 |
| 31 ft | 18.9 | 12.6 | 9.84 | 14.8 |
| 33 ft | 16.7 | 11.1 | 8.15 | 12.2 |
| 35 ft | 14.8 | 9.87 | 6.83 | 10.3 |
| 37 ft | 13.3 | 8.84 | 5.78 | 8.68 |
| 39 ft | 12.0 | 7.95 | 4.94 | 7.41 |
| 41 ft | 10.8 | 7.20 | 4.25 | 6.38 |
| 43 ft | 9.83 | 6.54 | 3.69 | 5.53 |
| 45 ft | 8.98 | 5.97 | 3.22 | 4.82 |
| 47 ft | 8.23 | 5.48 | 2.82 | 4.23 |
| 49 ft | 7.57 | 5.04 | 2.49 | 3.74 |
| 51 ft | 6.99 | 4.65 | 2.21 | 3.31 |
| 53 ft | 6.47 | 4.31 | 1.97 | 2.95 |
| 55 ft | 6.01 | 4.00 | 1.76 | 2.64 |
| 57 ft | 5.60 | 3.72 | 1.58 | 2.37 |
| 59 ft | 5.22 | 3.47 | 1.43 | 2.14 |
| 61 ft | 4.89 | 3.25 | 1.29 | 1.94 |
| 63 ft | 4.58 | 3.05 | 1.17 | 1.76 |
- Factored and allowable loads are limited by bending, or by shear where marked *.
- The deflection columns are the service loads that make the beam sag span/360 or span/240. Compare span/360 with the live load alone and span/240 with dead plus live load, the usual floor limits in IBC Table 1604.3.
Reading the table
At a 39 ft span, a W24×207 carries a factored load of 12.0 kips per foot (LRFD) or an allowable load of 7.95 kips per foot (ASD). A live load of 4.94 kips per foot would deflect it span/360, which is 1.30 in. The beam works if the factored load is under the first number and the live and total loads are under the deflection numbers. For other spans, supports or loads, open it in the beam designer, or follow the steel beam design guide to check one by hand.
W24×207 questions
What does W24×207 mean?
W means a wide flange shape. 24 is its nominal depth in inches (the actual depth is 25.7 in) and 207 is its weight in pounds per foot.
How much does a W24×207 weigh?
207 pounds per foot, so a 20 ft W24×207 weighs about 4,140 pounds.
How far can a W24×207 span?
It depends on the load. Braced along its length, it carries 103.2 kips per foot of factored load at 13 ft and 4.58 kips per foot at 63 ft; the load table has the spans in between. Floor beams are often 39 to 51 ft for this depth (span-to-depth ratios of about 18 to 24), where deflection usually governs.
Is a W24×207 a compact section?
Yes. Its flanges (bf/2tf = 4.14) and web (h/tw = 24.8) are both compact for bending in 50 ksi steel.