Design Examples of Steel and Steel-Concrete Composite Bridges - Finite Element Analysis and Design of Steel and Steel-Concrete Composite Bridges - page 308

L cr
i

1
l 1

l¼

l 1 ¼ 93 : 9 0 : 924 ¼ 86 : 7636

8640
86

1

l¼

7636 ¼ 1

:

158

86 :

The axial compressive force in the diagonal member D 5

( N Ed ¼ 526.5 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

h i

+ l 2

51+ a l 0

F¼ 0 : :

2

¼ 1

158 2 F¼ 0 : 51+0 : 49 1 ð : 158 0 : 2 Þ +1 : : 405

1

w¼

405 +

p ¼ 0 : 454 but w 1 : 0

405 2 158 2

1 : 1 : 1 :

0 : 454 13,520 275

1

Then, N b , Rd ¼ ¼ 1,534,520N

: 1

N b , Rd ¼ 1534 : 5kN > N Ed ¼ 526 : 5 kN Then O ð : K : Þ

It should be noted that the same cross section used for member D 5 can
also be used for the diagonal tension member D 4 .

4.3.3.23 Design of the Diagonal Tension Member D 3
The diagonal member D 3 , shown in Figure 4.78 , carrying a maximum ten-
sile design force of 4086.1 kN can be designed adopting the same procedures
used with D 5 as follows:
The bolts used in connecting the member with gusset plates are M27
high-strength pretensioned bolts having a clearance of 3 mm (hole diameter
Ø ¼ 30 mm):

2cm 2

A¼ 2 35 2+36 1 : 2 ¼ 183 :

2cm 2 A net ¼ 183 : 2 8 3 : 0 2 ¼ 135 :