Design Examples of Steel and Steel-Concrete Composite Bridges - Finite Element Analysis and Design of Steel and Steel-Concrete Composite Bridges - page 265

Haunch Equivalent to 1 cm slab thickness ð Þ ¼ 0 : 25 2 ¼ 0 : 5kN = m

Own weight of stringer ¼ 1 : 5kN = m
Total dead load ¼ g vk ¼ 15 m

Assuming the stringers are simply supported by the cross girders, we can
calculate the maximum shear force and bending moment due to dead loads
on an intermediate stringer (see Figure 4.39 ) as follows:
Q D : L : ¼ g vk L

: 5kN =

=

2 ¼ 15

:

5 6

=

2 ¼ 46

:

5kN

M D : L : ¼ g vk L 2 5 6 2 = 8 ¼ 15 : = 8 ¼ 69 : 75 kNm

Live Loads
The live loads acting on the highway bridge conform to Load Model 1,
which represents the static and dynamic effects of vertical loading due to
normal road traffic as specified in EC1 [3.1]. To determine the worst cases
of loading on an intermediate stringer due to live loads, we can study a lateral
section through vehicles and a lateral section through distributed loads of
Load Model 1 acting on the bridge, as shown in Figure 4.40 . From the sec-
tion through vehicles, we find that the maximum concentrated load trans-
ferred to the stringer is 200 kN, while from the section through distributed
loads, we find that the maximum distributed load transferred to the stringer is
14.34 kN/m. Therefore, the load distribution transferred to the stringer in
the longitudinal direction is as shown in Figure 4.41 . Two cases of loading
for the evaluation of maximum bending moment due to live loads on a

g vk = 15.5 kN/m

6 m

46.5 kN

+

S.F.D.

-

46.5 kN

B.M.D.

+

69.75 kN.m
Figure 4.39 Straining actions from dead loads acting on an intermediate stringer.