sm9 76

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PROBLEM (*9.76) A short column made of a W6 x 25 x 12 wide-flange section(see Table B.8) is
subjected to an eccentric axial load of P as shown in Fig. P9.76. If the maximum compressive stress is
limited to all
σ
, what is the largest permissible values of the distance e?
Given: P = 10 kips, all
σ
= 15 ksi
*SOLUTION
For
62512W×× steel section (Table B.8):
442
22.1 . 2.99 . 3.55 .
zy
I
in I in A in===
4 . 6.03 .
f
wind in==
We have
3.015 .
2
Ad
y
in=− =
2.
2f
A
w
zin==
2.9 2.9(10)
z
MP==
29 .kip in=⋅
10
y
M
Pe e
=
−=−
Hence
yA
zA
Azy
M
z
MyP
AI I
σ =− − +
or
[]
yzA
yA
Az
IMy P
MzI A
σ
=++
2.99 29(3.015) 10
[(15)]
2 22.1 3.55
=++−12.299 .kip in
=
−⋅
Then
12.299 1.23 .
10
y
M
ein
P
−
=− =− =
A
e
d
y
z
C
wf
P