Design Examples of Steel and Steel-Concrete Composite Bridges - Finite Element Analysis and Design of Steel and Steel-Concrete Composite Bridges - page 454

See Figure 4.210 for the direction of the forces. Also, the reactions from
upper and lower wind bracings ( R tot ) (see Figure 4.210 for the direction of
the forces) were previously calculated as follows:
R tot ¼ 492 6kN

We can now determine the normal stress distribution due to the applied
loads, shown in Figure 4.210 , on the concrete foundation as follows:

:

M y
I y x

N
A

M x
I x y

f ¼

N
A ¼

9 10 3
950 1100 ¼ 4

:

4433

: 24MPa

6 10 3 M x

I x y ¼

492 290

950 1100 3

:

550 ¼ 0 : 75MPa

= 12

M y
I y x ¼

468 10 3 290

1100 950 3 12 475 ¼ 0

: 82MPa

=

81MPa
f min ¼ 4 : 24 + 0 : 75 + 0 : 82 ¼ 2 : 67MPa
The critical bending moment on the base plate of the hinged bearing is at
section s - s shown in Figure 4.210 :
M ¼ 0

f max ¼ 4 : 24 0 : 75 0 : 82 ¼ 5 :

ð : 5 400 4 : 49 Þ 1100 400 = 3+ 0 ð : 5 400 5 : 81 Þ 1100

400 2 = 3 ¼ 472,560,000Nmm

t 4

4 ¼ 275 t 4

W pl ¼ 1100

f y
g M0
472,560,000
275 t 4

M
W pl ¼

340
1

¼

: 0

Then, t 4 ¼ 71.1 mm, taken as 75 mm.
The normal stresses at section s 1 - s 1 , shown in Figure 4.210 , of the line
rocker bearing can be checked as follows:
M x ¼ 492 6 10 3 : 215 ¼ 105,909,000Nmm :

M y ¼ 468 10 3 215 ¼ 100,620,000Nmm :

9 10 3
150 800 ¼ 36

N
A ¼

4433 :

: 95MPa