Properties of Sections

1

y x

4

4rII yxπ

==

==2

4rJ π polar moment of inertia

2rA π= 9

10=λ

2

y x t

trII yx

3π≅=

trJ 32π≅ rtA π2≅

2=λ

3

y h x b

12

3bhIx = 12

3hbI y = bhA =

56

=λ 3hbJ β=

: bhFor ≥

⎟⎟⎠

⎞⎜⎜⎝

⎛−−≅ 4

4

12121.0

31

hb

hbβ

4

tf y x h tw b

( )fwx bthth

I 36

2

+≅

( )wfy htbtbI 36

2

+≅ ( )wf htbtA += 2

fw

wf

htbttt

hbJ+

≅ 222 wht

A2

=λ

5

y tw h x tf b

( )fwx bththI 612

2

+≅

6

3f

y

tbI ≅ fw bthtA 2+≅

( )33 231

fw bthtJ +≅ wdtA ='

r r

r

λ = shear factor = A/A’ J = St. Venant’s torsional constant A’ = effective shear area