Design Examples of Steel and Steel-Concrete Composite Bridges - Finite Element Analysis and Design of Steel and Steel-Concrete Composite Bridges - page 403

4

4
6
14
4

17

7

Figure 4.161 The designed roller and hinged line rocker fabricated steel bearings.

longitudinal and lateral directions of the bearing base, respectively. Similar to
the roller bearing, the material of construction for the bearings is cast iron
steel (ISO 3755) 340-550 having a yield stress of 340 MPa and an ultimate
stress of 550 MPa. It should be noted that the overall height of the hinged
bearing must be exactly the same as that of the roller bearing. The general
layout and assumed dimensions of the hinged line rocker bearing are shown
in Figure 4.161 . The traction Q lak and braking Q lbk forces can be calculated
as follows:

Q lak ¼ 33 L a , b ¼ 33 27 ¼ 991 kN 1000 kN ½ , for Load Models 71

Q lbk ¼ 20 L a , b ¼ 20 27 ¼ 540
6000 kN ½ , for Load Models 71,SW = 0,SW = 2 and HSLM

Total the braking and traction forces ( Q tot ) ¼ 1431 kN (see Figure 4.160
for the direction of the forces). Also, the reaction from the lower wind brac-
ings ( R ) (see Figure 4.160 for the direction of the forces) was previously cal-
culated as follows:

6kN
We can now determine the normal stress distribution due to the applied
loads, shown in Figure 4.160 , on the concrete foundation as follows:

R tot ¼ 381 :

N
A

M x
I x y

M y
I y x

f ¼

N
A ¼

3,132,800
950 1100 ¼ 3

: 0MPa

M x
I x y ¼

381 240

950 1100 3

: 6 10 3

550 ¼ 0 : 49MPa

=

12

1431 10 3 M y

I y x ¼

240
1100 950 3

12 475 ¼ 2

: 08MPa

=