W12×152 Steel Beam
A W12×152 is a wide flange steel beam 13.7 inches deep with 12.5-inch flanges, weighing 152 pounds per foot. In ASTM A992 steel (Fy = 50 ksi) it has a design bending strength of 911 kip-ft (LRFD) when its compression flange is braced, and a design shear strength of 358 kips.
Design a W12×152 beam Opens a 21 ft span in the free beam designer.
W12×152 dimensions
| Dimension | Value |
|---|---|
| Depth, d | 13.7 in |
| Flange width, bf | 12.5 in |
| Flange thickness, tf | 1.40 in |
| Web thickness, tw | 0.870 in |
| Distance to web toe of fillet, kdes | 2.00 in |
| Distance between flange centroids, ho | 12.30 in |
| Cross-sectional area, A | 44.7 in2 |
| Weight | 152 lb/ft |
Dimensions are AISC design values. Detailing dimensions are rounded to the nearest 1/16 in.
W12×152 section properties
| Property | Strong axis (x) | Weak axis (y) |
|---|---|---|
| Moment of inertia, I | 1430 in4 | 454 in4 |
| Elastic section modulus, S | 209 in3 | 72.8 in3 |
| Plastic section modulus, Z | 243 in3 | 111 in3 |
| Radius of gyration, r | 5.66 in | 3.19 in |
| Torsion and slenderness | Value |
|---|---|
| Torsional constant, J | 25.8 in4 |
| Warping constant, Cw | 17200 in6 |
| Effective radius of gyration, rts | 3.66 in |
| Flange slenderness, bf/2tf | 4.46 |
| Web slenderness, h/tw | 11.2 |
W12×152 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 = 911 kip-ft | Mn/Ω = 606 kip-ft |
| Shear | φVn = 358 kips | Vn/Ω = 238 kips |
If the compression flange isn't braced, the beam can buckle sideways before it yields. Up to Lp = 11.3 ft between braces it keeps its full strength; past Lr = 70.6 ft it buckles elastically. With uniform moment between braces (Cb = 1.0):
| Unbraced length, Lb | φMn (LRFD) | Mn/Ω (ASD) |
|---|---|---|
| Braced | 911 kip-ft | 606 kip-ft |
| 10 ft | 911 kip-ft | 606 kip-ft |
| 11.3 ft (Lp) | 911 kip-ft | 606 kip-ft |
| 20 ft | 858 kip-ft | 571 kip-ft |
| 30 ft | 797 kip-ft | 530 kip-ft |
| 40 ft | 736 kip-ft | 489 kip-ft |
| 50 ft | 674 kip-ft | 449 kip-ft |
| 60 ft | 613 kip-ft | 408 kip-ft |
| 70 ft | 552 kip-ft | 367 kip-ft |
| 70.6 ft (Lr) | 548 kip-ft | 365 kip-ft |
| 80 ft | 483 kip-ft | 321 kip-ft |
| 90 ft | 428 kip-ft | 285 kip-ft |
| 100 ft | 385 kip-ft | 256 kip-ft |
| 110 ft | 349 kip-ft | 232 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.
W12×152 load table by span
The largest uniform load a simply supported W12×152 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 0.152 kips per foot.
| Span | Factored load (LRFD) | Allowable load (ASD) | Load at span/360 | Load at span/240 |
|---|---|---|---|---|
| 7 ft | 102.2* | 68.1* | 179.1 | 268.7 |
| 9 ft | 79.5* | 53.0* | 84.3 | 126.4 |
| 11 ft | 60.2 | 40.1 | 46.2 | 69.2 |
| 13 ft | 43.1 | 28.7 | 28.0 | 41.9 |
| 15 ft | 32.4 | 21.6 | 18.2 | 27.3 |
| 17 ft | 25.2 | 16.8 | 12.5 | 18.8 |
| 19 ft | 20.2 | 13.4 | 8.96 | 13.4 |
| 21 ft | 16.5 | 11.0 | 6.63 | 9.95 |
| 23 ft | 13.8 | 9.17 | 5.05 | 7.57 |
| 25 ft | 11.7 | 7.76 | 3.93 | 5.90 |
| 27 ft | 10.0 | 6.65 | 3.12 | 4.68 |
| 29 ft | 8.67 | 5.77 | 2.52 | 3.78 |
| 31 ft | 7.59 | 5.05 | 2.06 | 3.09 |
| 33 ft | 6.69 | 4.45 | 1.71 | 2.56 |
- 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 21 ft span, a W12×152 carries a factored load of 16.5 kips per foot (LRFD) or an allowable load of 11.0 kips per foot (ASD). A live load of 6.63 kips per foot would deflect it span/360, which is 0.70 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.
W12×152 questions
What does W12×152 mean?
W means a wide flange shape. 12 is its nominal depth in inches (the actual depth is 13.7 in) and 152 is its weight in pounds per foot.
How much does a W12×152 weigh?
152 pounds per foot, so a 20 ft W12×152 weighs about 3,040 pounds.
How far can a W12×152 span?
It depends on the load. Braced along its length, it carries 102.2 kips per foot of factored load at 7 ft and 6.69 kips per foot at 33 ft; the load table has the spans in between. Floor beams are often 21 to 27 ft for this depth (span-to-depth ratios of about 18 to 24), where deflection usually governs.
Is a W12×152 a compact section?
Yes. Its flanges (bf/2tf = 4.46) and web (h/tw = 11.2) are both compact for bending in 50 ksi steel.