W10×49 Steel Beam

A W10×49 is a wide flange steel beam 10 inches deep with 10-inch flanges, weighing 49 pounds per foot. In ASTM A992 steel (Fy = 50 ksi) it has a design bending strength of 227 kip-ft (LRFD) when its compression flange is braced, and a design shear strength of 102 kips.

Weight49 lb/ft
Depth10 in
Ix272 in4
Sx54.6 in3
Zx60.4 in3
φMn227 kip-ft

Design a W10×49 beam Opens a 15 ft span in the free beam designer.

bf = 10 in d = 10 in tw = 0.34 in tf = 0.56 in

W10×49 dimensions

DimensionValue
Depth, d10.0 in
Flange width, bf10.0 in
Flange thickness, tf0.560 in
Web thickness, tw0.340 in
Distance to web toe of fillet, kdes1.06 in
Distance between flange centroids, ho9.44 in
Cross-sectional area, A14.4 in2
Weight49 lb/ft

Dimensions are AISC design values. Detailing dimensions are rounded to the nearest 1/16 in.

W10×49 section properties

PropertyStrong axis (x)Weak axis (y)
Moment of inertia, I272 in493.4 in4
Elastic section modulus, S54.6 in318.7 in3
Plastic section modulus, Z60.4 in328.3 in3
Radius of gyration, r4.35 in2.54 in
Torsion and slendernessValue
Torsional constant, J1.39 in4
Warping constant, Cw2070 in6
Effective radius of gyration, rts2.84 in
Flange slenderness, bf/2tf8.93
Web slenderness, h/tw23.1

W10×49 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.

StrengthLRFDASD
Bending, compression flange bracedφMn = 227 kip-ftMn/Ω = 151 kip-ft
ShearφVn = 102 kipsVn/Ω = 68.0 kips

If the compression flange isn't braced, the beam can buckle sideways before it yields. Up to Lp = 9.0 ft between braces it keeps its full strength; past Lr = 31.6 ft it buckles elastically. With uniform moment between braces (Cb = 1.0):

Unbraced length, LbφMn (LRFD)Mn/Ω (ASD)
Braced227 kip-ft151 kip-ft
9.0 ft (Lp)227 kip-ft151 kip-ft
10 ft223 kip-ft148 kip-ft
20 ft186 kip-ft124 kip-ft
30 ft149 kip-ft99.2 kip-ft
31.6 ft (Lr)143 kip-ft95.3 kip-ft
40 ft109 kip-ft72.2 kip-ft
50 ft84.6 kip-ft56.3 kip-ft
60 ft69.4 kip-ft46.2 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.

W10×49 load table by span

The largest uniform load a simply supported W10×49 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 0.049 kips per foot.

SpanFactored load (LRFD)Allowable load (ASD)Load at span/360Load at span/240
5 ft40.8*27.2*93.5140.2
6 ft34.0*22.7*54.181.2
7 ft29.1*19.4*34.151.1
8 ft25.5*17.0*22.834.2
9 ft22.414.916.024.0
10 ft18.112.111.717.5
11 ft15.09.968.7813.2
12 ft12.68.376.7610.1
13 ft10.77.135.327.98
14 ft9.246.154.266.39
15 ft8.055.363.465.19
16 ft7.084.712.854.28
17 ft6.274.172.383.57
18 ft5.593.722.003.01
19 ft5.023.341.702.56
20 ft4.533.011.462.19
21 ft4.112.731.261.89
22 ft3.742.491.101.65
23 ft3.432.280.961.44
24 ft3.152.090.851.27
25 ft2.901.930.751.12
  • 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 15 ft span, a W10×49 carries a factored load of 8.05 kips per foot (LRFD) or an allowable load of 5.36 kips per foot (ASD). A live load of 3.46 kips per foot would deflect it span/360, which is 0.50 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.

W10×49 questions

What does W10×49 mean?

W means a wide flange shape. 10 is its nominal depth in inches (the actual depth is 10.0 in) and 49 is its weight in pounds per foot.

How much does a W10×49 weigh?

49 pounds per foot, so a 20 ft W10×49 weighs about 980 pounds.

How far can a W10×49 span?

It depends on the load. Braced along its length, it carries 40.8 kips per foot of factored load at 5 ft and 2.90 kips per foot at 25 ft; the load table has the spans in between. Floor beams are often 15 to 20 ft for this depth (span-to-depth ratios of about 18 to 24), where deflection usually governs.

Is a W10×49 a compact section?

Yes. Its flanges (bf/2tf = 8.93) and web (h/tw = 23.1) are both compact for bending in 50 ksi steel.