Design Examples of Steel and Steel-Concrete Composite Bridges - Finite Element Analysis and Design of Steel and Steel-Concrete Composite Bridges - page 261

wind bracings ( R tot ) (see Figure 4.34 for the direction of the forces) were
previously calculated as follows:

15 kN
We can now determine the normal stress distribution due to the applied
loads, shown in Figure 4.34 , on the concrete foundation as follows:

R tot ¼ 449 : 05 + 95 : 1 ¼ 544 :

N
A

M x
I x y

M y
I y x

f ¼

N
A ¼

3,327,200
950 1100 ¼ 3

: 18MPa

15 10 3 M x

I x y ¼

544 240

950 1100 3

:

550 ¼ 0 : 68MPa

= 12

1590 10 3 M y

I y x ¼

240
1100 950 3 12 475 ¼ 2

: 31MPa

=

f max ¼ 3 : 18 0 : 68 2 : 31 ¼ 6 : 17MPa

f min ¼ 3 : 18 + 0 : 68 + 2 : 31 ¼ 0 : 19MPa

The critical bending moment on the base plate of the hinged bearing is at
section s - s , shown in Figure 4.34 :

M ¼ 0 ð : 5 400 3 : 65 Þ 1100 400 = 3+ 0 ð : 5 400 6 : 17 Þ 1100

400 2 = 3
¼ 469,040,000Nmm

W pl ¼ 1100 t 4 = 4 ¼ 275 t 4

M
W pl ¼

f y
g M0

469,040,000
275 t 4

340
1

¼

: 0

Then, t 4 ¼ 70.8 mm, taken as 75 mm.
The normal stresses at section s 1 - s 1 , shown in Figure 4.34 , of the line
rocker bearing can be checked as follows:

15 10 3 M x ¼ 544 : 165 ¼ 89,784,750Nmm :

M y ¼ 1590 10 3 165 ¼ 262,350,000Nmm :