Design Examples of Steel and Steel-Concrete Composite Bridges - Finite Element Analysis and Design of Steel and Steel-Concrete Composite Bridges - page 436

It should be noted that the vertical member must be inside the gusset
plates spaced at a constant distance ( b ) of 400 mm. Let us start by assuming
the flange thickness of 40 mm and web thickness of 30 mm. To classify the
cross section chosen (see Figure 4.197 ) ,

s

235
f y

r

235
275

e ¼ ¼ ¼ 0 : 924

C 1 ¼ 107mm, t fl ¼ 40, C 1 = t fl ¼ 107 =

40 ¼ 2

: < ð Þ

8 Flange is Class 1

C 2 ¼ 264mm, t w ¼ 30, C 2 = t fl ¼ 264 = 30 ¼ 8 : 8 < 33 0 : 924

¼ 30 : 5 Web is Class 1 ð Þ

0 ¼ 292 cm 2 A¼ 2 26 4+28 3 :

¼ 65,189 cm 4

0 28 3 12 + 2 26 4 3 12 + 26 4 16 2 I x ¼ 3 : = =

I y ¼ 28 3 3 12 + 2 4 26 3 12 ¼ 11,780 cm 4

= =

r

I x
A

r

65,189
292

i x ¼ ¼ ¼ 14 : 94 cm

r

I y
A

r

11,780
292

¼ ¼ 6 :

i y ¼ 35 cm

l b y ¼ 3600mm
l b x ¼ 4000mm

L cr
i

1
l 1

l¼

l 1 ¼ 93 :

9 0

:

924 ¼ 86

:

7636

3600
63

1

l¼

5 7636 ¼ 0

: 653

: 86 :

The axial compressive force in the vertical member V 1

( N Ed ¼ 4433.9 kN):

N Ed
N b , Rd 1

: 0

wAf y
g M1

where N b , Rd ¼

1

p

F 2

w¼ but w 1 : 0

l 2 F +