Design Examples of Steel and Steel-Concrete Composite Bridges - Finite Element Analysis and Design of Steel and Steel-Concrete Composite Bridges - page 363

33MPa
The critical bending moment on the base plate of the hinged bearing is at
section s - s shown in Figure 4.124 :
M ¼ 0

f min ¼ 2 : 098 + 0 : 21 + 0 : 56 ¼ 1 :

ð : 5 400 2 : 22 Þ 1100 400 = 3+ 0 ð : 5 400 2 : 87 Þ 1100

400 2 = 3 ¼ 233,493,333Nmm

W pl ¼ 1100 t 4 = 4 ¼ 275 t 4

f y
g M0
233,493,333
275 t 4

M
W pl ¼

340
1

¼

: 0

Then, t 4 ¼ 49.97 mm, taken as 55 mm.
The normal stresses at section s 1 - s 1 , shown in Figure 4.124 , of the line
rocker bearing can be checked as follows:

9 10 3

M x ¼ 212 : 135 ¼ 28,741,500Nmm :

6 10 3 M y ¼ 489 : 135 ¼ 66,096,000Nmm :

36 10 3
150 900 ¼ 16

N
A ¼

2193 :

: 25MPa

M x
I x y ¼

28,741,500
150 900 3 12 450 ¼ 1

: 42MPa

=

M y
I y x ¼

66,096,000
900 150 3 12 75 ¼ 19

: 56MPa

=

f max ¼ 16 ð : 25 + 1 : 42 + 19 : 56 Þ ¼ 37 : 23MPa < 340MPa Then O ð : K : Þ

4.5 DESIGN EXAMPLE OF A DOUBLE-TRACK PLATE GIRDER
PONY RAILWAY STEEL BRIDGE
The fourth design example presented in this chapter is for a double-track
open-timber floor plate girder pony railway steel bridge. The general layout
of the double-track pony bridge is shown in Figures 4.126 and 4.127 . The
bridge has simply supported ends, a length between supports of 27 m, and
an overall length of 28 m. The width of the bridge (spacing between main