Design Examples of Steel and Steel-Concrete Composite Bridges - Finite Element Analysis and Design of Steel and Steel-Concrete Composite Bridges - page 255

0.3 cm clearance), we can determine the horizontal shear force ( H ) per bolt
and the vertical shear per bolt ( V ) as follows:

H ¼ Area from centrelines between bolts
average stress at the bolt location f a ðÞ
f av ¼ 140 275 6MPa

H ¼ 100 3 ð Þ 16 251 : 6 = 2 ¼ 140896N ¼ 140 : 9kN
V¼ maximum shear resisted by web/total number of bolts.
Maximum shear resisted by web was previously calculated in the check
of the safety of the plate girder against shear stresses and was 8313.8 kN.
The total number of bolts in one side of the splice is 58 bolts:
V ¼ 8313

= 153 ¼ 251 :

: 8 = 58 ¼ 143 : 3kN

The resultant of the forces per bolt ( R ) is equal to

p

140

¼ 201 kN, which is less than 206 kN (the resistance of
the bolt in double shear). Then O.K.

:

9 2 + 143

:

3 2

Flange Splices

Maximum force in the upper flange ¼ 180 275 100 = 1000 ¼ 4950 kN

N flange ð Þ 4950 = 206 ¼ 24 bolts 6 rows of four bolts in double shear ð Þ

4.2.13 Design of Roller Steel Fabricated Bearings
Let us now design the roller steel fabricated bearings shown in Figure 4.1 and
detailed in Figure 4.33 . The maximum vertical reaction at the supports of
the main plate girder was previously calculated under dead and live loads
with dynamic effect ( R D+L+ F ), which was 3327.2 kN. 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.

Design of the Sole Plate
The reaction ( R D+L+ F ) can be assumed as two equal concentrated loads at
two points, which are the centers of gravity of half of the load bearing
stiffener section shown in Figure 4.33 . To determine the centers of gravity
(distance e ), we can take the first area moment around the axis z - z , shown in
Figure 4.33 , as follows:

2 25 1 : 2 0 : 6+23 : 2 1 : 6 11 : 6 466 : 592

e ¼ ¼

12 ¼ 4 : 8cm 2 25 1 : 2+23 : 2 1 : 6 97 :