W36×247 Steel Beam
A W36×247 is a wide flange steel beam 36.7 inches deep with 16.5-inch flanges, weighing 247 pounds per foot. In ASTM A992 steel (Fy = 50 ksi) it has a design bending strength of 3,863 kip-ft (LRFD) when its compression flange is braced, and a design shear strength of 881 kips.
Design a W36×247 beam Opens a 56 ft span in the free beam designer.
W36×247 dimensions
| Dimension | Value |
|---|---|
| Depth, d | 36.7 in |
| Flange width, bf | 16.5 in |
| Flange thickness, tf | 1.35 in |
| Web thickness, tw | 0.800 in |
| Distance to web toe of fillet, kdes | 2.30 in |
| Distance between flange centroids, ho | 35.35 in |
| Cross-sectional area, A | 72.5 in2 |
| Weight | 247 lb/ft |
Dimensions are AISC design values. Detailing dimensions are rounded to the nearest 1/16 in.
W36×247 section properties
| Property | Strong axis (x) | Weak axis (y) |
|---|---|---|
| Moment of inertia, I | 16700 in4 | 1010 in4 |
| Elastic section modulus, S | 913 in3 | 123 in3 |
| Plastic section modulus, Z | 1030 in3 | 190 in3 |
| Radius of gyration, r | 15.2 in | 3.74 in |
| Torsion and slenderness | Value |
|---|---|
| Torsional constant, J | 34.7 in4 |
| Warping constant, Cw | 316000 in6 |
| Effective radius of gyration, rts | 4.42 in |
| Flange slenderness, bf/2tf | 6.11 |
| Web slenderness, h/tw | 40.1 |
W36×247 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 = 3,863 kip-ft | Mn/Ω = 2,570 kip-ft |
| Shear | φVn = 881 kips | Vn/Ω = 587 kips |
If the compression flange isn't braced, the beam can buckle sideways before it yields. Up to Lp = 13.2 ft between braces it keeps its full strength; past Lr = 39.5 ft it buckles elastically. With uniform moment between braces (Cb = 1.0):
| Unbraced length, Lb | φMn (LRFD) | Mn/Ω (ASD) |
|---|---|---|
| Braced | 3,863 kip-ft | 2,570 kip-ft |
| 10 ft | 3,863 kip-ft | 2,570 kip-ft |
| 13.2 ft (Lp) | 3,863 kip-ft | 2,570 kip-ft |
| 20 ft | 3,484 kip-ft | 2,318 kip-ft |
| 30 ft | 2,925 kip-ft | 1,946 kip-ft |
| 39.5 ft (Lr) | 2,397 kip-ft | 1,595 kip-ft |
| 40 ft | 2,347 kip-ft | 1,561 kip-ft |
| 50 ft | 1,699 kip-ft | 1,130 kip-ft |
| 60 ft | 1,328 kip-ft | 883 kip-ft |
| 70 ft | 1,090 kip-ft | 725 kip-ft |
| 80 ft | 926 kip-ft | 616 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.
W36×247 load table by span
The largest uniform load a simply supported W36×247 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 0.247 kips per foot.
| Span | Factored load (LRFD) | Allowable load (ASD) | Load at span/360 | Load at span/240 |
|---|---|---|---|---|
| 18 ft | 95.4 | 63.5 | 123.0 | 184.5 |
| 20 ft | 77.3 | 51.4 | 89.7 | 134.5 |
| 22 ft | 63.8 | 42.5 | 67.4 | 101.1 |
| 24 ft | 53.6 | 35.7 | 51.9 | 77.9 |
| 26 ft | 45.7 | 30.4 | 40.8 | 61.2 |
| 28 ft | 39.4 | 26.2 | 32.7 | 49.0 |
| 30 ft | 34.3 | 22.8 | 26.6 | 39.9 |
| 32 ft | 30.2 | 20.1 | 21.9 | 32.8 |
| 34 ft | 26.7 | 17.8 | 18.3 | 27.4 |
| 36 ft | 23.8 | 15.9 | 15.4 | 23.1 |
| 38 ft | 21.4 | 14.2 | 13.1 | 19.6 |
| 40 ft | 19.3 | 12.8 | 11.2 | 16.8 |
| 42 ft | 17.5 | 11.7 | 9.68 | 14.5 |
| 44 ft | 16.0 | 10.6 | 8.42 | 12.6 |
| 46 ft | 14.6 | 9.72 | 7.37 | 11.1 |
| 48 ft | 13.4 | 8.92 | 6.49 | 9.73 |
| 50 ft | 12.4 | 8.22 | 5.74 | 8.61 |
| 52 ft | 11.4 | 7.60 | 5.10 | 7.65 |
| 54 ft | 10.6 | 7.05 | 4.56 | 6.83 |
| 56 ft | 9.85 | 6.56 | 4.09 | 6.13 |
| 58 ft | 9.19 | 6.11 | 3.68 | 5.52 |
| 60 ft | 8.58 | 5.71 | 3.32 | 4.98 |
| 62 ft | 8.04 | 5.35 | 3.01 | 4.52 |
| 64 ft | 7.54 | 5.02 | 2.74 | 4.11 |
| 66 ft | 7.09 | 4.72 | 2.50 | 3.74 |
| 68 ft | 6.68 | 4.45 | 2.28 | 3.42 |
| 70 ft | 6.31 | 4.20 | 2.09 | 3.14 |
| 72 ft | 5.96 | 3.97 | 1.92 | 2.88 |
| 74 ft | 5.64 | 3.75 | 1.77 | 2.66 |
| 76 ft | 5.35 | 3.56 | 1.63 | 2.45 |
| 78 ft | 5.08 | 3.38 | 1.51 | 2.27 |
| 80 ft | 4.83 | 3.21 | 1.40 | 2.10 |
| 82 ft | 4.60 | 3.06 | 1.30 | 1.95 |
| 84 ft | 4.38 | 2.91 | 1.21 | 1.82 |
| 86 ft | 4.18 | 2.78 | 1.13 | 1.69 |
| 88 ft | 3.99 | 2.65 | 1.05 | 1.58 |
| 90 ft | 3.81 | 2.54 | 0.98 | 1.48 |
| 92 ft | 3.65 | 2.43 | 0.92 | 1.38 |
- 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 56 ft span, a W36×247 carries a factored load of 9.85 kips per foot (LRFD) or an allowable load of 6.56 kips per foot (ASD). A live load of 4.09 kips per foot would deflect it span/360, which is 1.87 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.
W36×247 questions
What does W36×247 mean?
W means a wide flange shape. 36 is its nominal depth in inches (the actual depth is 36.7 in) and 247 is its weight in pounds per foot.
How much does a W36×247 weigh?
247 pounds per foot, so a 20 ft W36×247 weighs about 4,940 pounds.
How far can a W36×247 span?
It depends on the load. Braced along its length, it carries 95.4 kips per foot of factored load at 18 ft and 3.65 kips per foot at 92 ft; the load table has the spans in between. Floor beams are often 55 to 73 ft for this depth (span-to-depth ratios of about 18 to 24), where deflection usually governs.
Is a W36×247 a compact section?
Yes. Its flanges (bf/2tf = 6.11) and web (h/tw = 40.1) are both compact for bending in 50 ksi steel.