W33X318 Steel Beam — Section Properties

Dimensions

Property Value Unit
Depth (d) 35.20 in (894.1 mm)
Flange Width (bf) 16 in (406.4 mm)
Flange Thickness (tf) 1.89 in
Web Thickness (tw) 1.04 in
Area (A) 93.70 in² (604.6 cm²)
Weight 318 lb/ft (473 kg/m)

Elastic Section Properties

Property Strong Axis (X-X) Weak Axis (Y-Y) Unit
Moment of Inertia (I) 19,500 1,290 in⁴
Elastic Section Modulus (S) 1,110 161 in³
Plastic Section Modulus (Z) 1,270 250 in³
Radius of Gyration (r) 14.50 3.71 in

Torsional Properties

Property Value Unit
Torsional Constant (J) 84.40 in⁴
Warping Constant (Cw) 357,000 in⁶
Distance Between Flange Centroids (ho) 33.30 in
Effective Radius (rts) 4.40 in

Design Resources

Frequently Asked Questions

What is the weight of a W33X318 beam? 318 lb/ft (473 kg/m). A 40-ft length weighs approximately 12,720 lbs.

What is the section modulus of W33X318? Sx = 1110 in³ (strong axis) and Sy = 161 in³ (weak axis). The plastic section modulus Zx = 1270 in³ and Zy = 250 in³.

What steel grade is standard for W33X318? 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 W33X318? Ix = 19500 in⁴ about the strong axis and Iy = 1290 in⁴ about the weak axis. The radius of gyration is rx = 14.50 in and ry = 3.71 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.