Design Examples of Steel and Steel-Concrete Composite Bridges - Finite Element Analysis and Design of Steel and Steel-Concrete Composite Bridges - page 314

It should be noted that the thickness used (1 cm) is the minimum
thickness that can be used in bridges; therefore, this section will be used also
for the zero member—under dead and live load cases of loading, lower
chord member L 1 .

4.3.3.30 Design of Stringer-Cross Girder Connection
The stringer is designed as a simply supported beam on cross girders; therefore,
the connection is mainly transferring shear forces (maximum reaction from
stringers of 604.5 kN) (see Figure 4.85 ) . Using M27 high-strength preten-
sioned bolts of grade 8.8, having f ub of 800 MPa, shear area A of 4.59 cm 2 ,
and gross area A g of 5.73 cm 2 , we can determine the required number of bolts,
following the rules specified in EC3 (BS EN 1993-1-8) [2.13], as follows:

a V f ub A
g M2

F v , Rd ¼

0 : 6 800 459

1

F v , Rd ¼ ¼ 176,256N

: 25

Then, F v,Rd equals 176 kN (for bolts in single shear) and 353 kN (for bolts in
double shear):

k s nm
g M3 F p , C

F s , Rd ¼

F p , C ¼ 0 : 7 f ub A s ¼ 0 : 7 800 573 ¼ 320,880N

1 : 0 1 : 0 0 : 4

F s , Rd , ser ¼ 320,880 ¼ 116,683 : 6N :

1 : 1

Q D+L+ f = 604.5 kN

N 1

N 2

Figure 4.85 The connection between a stringer and a cross girder.