1. Steel Construction Manual
American Institute of Steel Construction
Thirteenth Edition
Part 1
Dimensions and Properties 1

2. Wide-flange (W) Shapes
Most widely used section
Two flanges held apart by a web
Essentially parallel inner and outer flange surfaces
Section designation
Weight in pounds/per foot
W 24 x 55
Nominal depth in full inches
Nominal depths from 4-inch to 44 inch
Weights available from 9 lb/ft to 800 lb/ft

3. Wide-flange (W) Shapes
W 14 x 730
Actual depth is 22.4 inches
W 14 x 90
Actual depth is
14 inches
All shapes from W14 x 90 to W 14 x 730 have flat (T) part of web of 10 inches.
All these shapes can be stacked on each other 5

4. Major axis
Flange
Web
Weak axis
Designation

5. Actual depth
Cross-sectional area

6. Flange Properties
WebThickness

7. End of fillet transition between web and flange
Flat portion of web
Spacing between rows
of bolts in flange

8. Flange and web stability
Moment of Inertia (I), elastic section modulus (S), radius of gyration (r), plastic section modulus (Z) for strong and weak axes
Weight per foot
Flange and web stability
parameters

11. M-Shapes Not classified in ASTM 6 as W-, S- or HP- shapes
Same properties (A, d, tw, bf, etc) as W- shapes
Can have sloped inside flange or other features 11

12. American Standard (S) Shapes
16-2/3% slope on inner flange surface
Relatively narrow flanges and thicker webs when
compared to W shapes
Section designation
S24x121
Weight per foot
Nominal depth
Use is less common because of lower moment of inertia,
tapered flanges and low lateral stiffness

13. Narrow flange
Note: slope on inside of flange

14. Same properties as for W shapes14

15. Channels Nominal depth is same as actual depth Section designation
C15x50
Weight in pounds per foot
Actual depth
MC – Miscellaneous channel – Other than 2 on 12 slope on
inner flange

16. Property for design
Property for
detailing
Actual depth

17. Angles
For a single angle major axes do not correspond to x and y axes
Section designation
Short leg length
L6x4x3/4
Thickness of both legs
Long leg length
Equal leg and unequal leg angles available
Angles are best used in pairs as LLBB (Long-leg-
back-to-back) or SLBB (Short-leg-back-to-back).

18. Location of elastic centroid
Location of plastic centroid
X axis properties
Designation

19. Minor (weak) axis for a single angle
Y axis properties

20. Tees
WT -, MT- and ST- are obtained by shearing or thermal-cut from parent shape of W, M and S respectively
Two WT 22 x 131 can be made by cutting a W 44 x 262
Nominal depths and weights of a WT is exactly half
of the parent shape
Off-center cuts can be done but properties not listed in Manual
Used for top and bottom chords of trusses and diagonal bracing in buildings 20

21. Stem, not web

22. 22

23. Hollow Structural Shapes
Rectangular, Square or Round HSS
Welded or Seamless
Welded HSS made by welding sheet steel
Seamless made by extrusion of solid round bars
Outside longer dimension
HSS 10 x 4 x 3/8
Wall thickness
Section Designation
Outside shorter dimension 23

24. Strong axis structural properties
Outside Longer
Dimension
Strong axis structural properties
Actual Wall Thickness
Outside Shorter
Dimension
Design Wall Thickness = 0.93 x Actual Wall Thickness 24

25. Weak axis structural properties

26. Structural properties for
strong and weak axes
Equal outside dimensions

27. Nominal versus design thickness
Diameter over design thickness

28. Nominal wall thickness
Standard, x-strong and xx-strong designations

29. Double Angles 2L6x4x3/4 Major axes are now x and y
X axis properties may be obtained from x axis
properties of single angle
Y axis properties depend on separation between backs
angles and whether LLBB or SLBB 29

30. Long legs back-to-back Short legs back-to-back
Radius of gyration for compression members
Separation due to gusset plates

31. 31

32. Double Channels Designated as 2C or 2MC 2C15x50
Y axis properties depend on back-to-back separation
X axis properties can be obtained from x axis
properties of single channel 32

33. Y axis properties depend on back-to-back distance (gusset plate thicknesses) between individual channels

34. Suitable for Crane Girders
Channel
Moment of Inertia, Ixx
W shape
Weight

35. Nominal wall thickness

38. Preferred Specification
Limited availability
Steel Types

39. Plates > 8 inch width
Bars < 8 inch width
Thickness in inches