Design Examples of Steel and Steel-Concrete Composite Bridges - Finite Element Analysis and Design of Steel and Steel-Concrete Composite Bridges - page 441

3 d 1 =26 cm

y

2

2

18

x x

2

2

y

3

Figure 4.202 The cross section of the diagonal compression member D 2 .

¼ 51,588 cm 4

I x ¼ 2 2 30 3 12 + 2 26 3 3 5 2 = = 12 + 26 3 16 :

¼ 20,828 cm 4

I y ¼ 2 3 26 3 12 + 2 30 2 3 12 + 30 2 10 2 = =

r

I x
A

r

51,588
276

i x ¼ ¼ ¼ 13 : 67 cm

r

I y
A

r

20,828
276

i y ¼ ¼ ¼ 8 : 69 cm

l b y ¼ 5760mm
l b x ¼ 6400mm

L cr
i

1
l 1

l¼

l 1 ¼ 93 : 9 0 : 924 ¼ 86 : 7636

5760
86

1

l¼

9 7636 ¼ 0 : 764 : 86 :

The axial compressive force in the vertical member D 2

( N Ed ¼ 4706.6 kN):

N Ed
N b , Rd 1

: 0

wAf y
g M1

where N b , Rd ¼

1
F +

w¼ p but w 1 : 0

l 2

F 2