W12X120 Steel Beam — Section Properties

Dimensions

Property Value Unit
Depth (d) 13.10 in (332.7 mm)
Flange Width (bf) 12.30 in (312.4 mm)
Flange Thickness (tf) 1.11 in
Web Thickness (tw) 0.71 in
Area (A) 35.20 in² (227.1 cm²)
Weight 120 lb/ft (179 kg/m)

Elastic Section Properties

Property Strong Axis (X-X) Weak Axis (Y-Y) Unit
Moment of Inertia (I) 1,070 345 in⁴
Elastic Section Modulus (S) 163 56 in³
Plastic Section Modulus (Z) 186 85.40 in³
Radius of Gyration (r) 5.51 3.13 in

Torsional Properties

Property Value Unit
Torsional Constant (J) 12.90 in⁴
Warping Constant (Cw) 12,400 in⁶
Distance Between Flange Centroids (ho) 12 in
Effective Radius (rts) 3.56 in

Design Resources

Frequently Asked Questions

What is the weight of a W12X120 beam? 120 lb/ft (179 kg/m). A 40-ft length weighs approximately 4,800 lbs.

What is the section modulus of W12X120? Sx = 163 in³ (strong axis) and Sy = 56 in³ (weak axis). The plastic section modulus Zx = 186 in³ and Zy = 85.4 in³.

What steel grade is standard for W12X120? 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 W12X120? Ix = 1070 in⁴ about the strong axis and Iy = 345 in⁴ about the weak axis. The radius of gyration is rx = 5.51 in and ry = 3.13 in.

Related Pages


Educational reference only. Verify all section properties against the current AISC Manual and mill certificates before design. Results are PRELIMINARY — NOT FOR CONSTRUCTION.