Manual of Steel Construction

Part 1

Dimensions and Properties

C. C. Fu, Ph.D., P.E.University of Maryland at College Park

AISC Steel Construction Manual, 15th Edition

1

Wide-flange (W) Shapes

• Most widely used section

• Essentially parallel inner and outer flange surfaces

• Two flanges held apart by a web

W24x55

Section designation

Nominal depth

Weight per foot

2

Flange

Web

Major (strong) axis

Designation

Minor (weak) axis

3

Cross-sectional area

Actual depth

4

Web thicknessFlange properties

5

End of fillet transitionbetween web and flange

Flat portion of web

Spacing between rowsof bolts in flange

6

Weight per foot

Second moment, elastic section modulus,radius of gyration,plastic section modulusfor strong and weak axes

Flange and web stabilityparameters

Used for beam strength calculations

7

HP-Shapes

• Not classified in ASTM 6 as W-, S- or HP- shapes

• Same properties (A, d, tw, bf, etc) as W- shapes

M-Shapes

• Also known as bearing piles

• Similar to W-shapes, except their webs and flanges are of equal thickness and the depth and flange width are nominally equal for a given designation

8

American Standard (S) Shapes

• 16-2/3% slope on inner flange surface

S24x121

Section designation

Nominal depth

Weight per foot

• Relatively narrow flange when compared to W shapes

9

Note slope on inside of flange

Narrow flange

10

Same properties as for W shapes

11

Channels

• 16-2/3% slope on inner flange surface

C15x50

Section designation

Actual depth

Weight per foot

MC – Miscellaneous channel – 2 on 12 slope on inner flange

12

Actual depth

Property for design

Property fordetailing

13

Angles

14

L6x4x3/4

Section designation

Long leg length

Short leg length

Thickness

• Major axes do not correspond to X and Y axes

Designation

X axis properties

Location of plastic centroid

Location of elastic centroid

15

Y axis properties

Minor (weak) axis

16

Tees

• WT – cut from W shape

WT22x131 is cut from W44x262

• ST – cut from S shape

• MT – cut from M shape

17

Stem, not web

18

Reduction factor for slender stiffened compression elements 19

Hollow Structural Shapes (HSS)

• Rectangular (or square)

• Round

Steel Pipe

• Pipe diameter (Std., X-Strong, XX-Strong)

For example, Pipe 5 Std.

20

21

Torsion andwarping constants

Hollow Structural Shapes (HSS)

22

Nominal versusdesign thickness

Diameter over design thickness

23

Double Angles2L6x4x3/4

• 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

24

Long legs back-to-back Short legs back-to-back

Equal leg angles

25

Unequal leg angles

26

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 axisproperties of single channel

27

Y axis properties dependon back-to-backdistance betweenindividual channels

28

VQIb

29

Table 2-4 Applicable

ASTM Specifications

/Shapes

30

Table 2-6 Applicable

ASTM Specifications

/Fasteners

31