Design of Reinforced Concrete Railway Bridges with Spans from 3 to 9 meters: Design according to the Eurocodes and the Swedish National Annex

Abstract: National codes have been used in bridge design as well as for the design of other type of strutures in
Sweden and other European countries. However, in the last years, the old codes have begun to give
way to new common European design standards: the Eurocodes.
All existing bridges, designed according to the earlier codes are gradually getting older, and eventually
they will have to be either repaired/strengthened or replaced.
The aim of this thesis is to provide useful standard designs for short railway concrete bridges. Further,
the aim is provide a manual for their design without getting lost in the huge amount of information
that the Eurocodes offer. The focus is on the most important parts and an effort has been made to
make the design process fluent. The designed bridges have lengths between 3 and 9 meters and the
Swedish National Annex to the Eurocode has been considered. There will be some limitations in the
calculations, for example, the bridges are supposed to have straight tracks.
The work is related to the European Project MAINLINE, which has the aim to help to improve the
management of the European railway infrastructure.
The results show, as can be expected, that as the length of the bridge increases, the amount of
reinforcement also increases and so does the thickness of the beams. In Appendix A, the calculations
for a 6 meters long bridge is given in detail, as an example. A table with reinforcement distribution
and dimensions is given for each length, as well as final drawings.
When the results obtained are compared to the ones obtained using the Spanish National Annex for
the Eurocode, it can be seen that the two designs are quite similar. The differences are due to some
safety factors and coefficients, but they do not make a big change when all the calculations are done.
Sometimes the crack width is the most determinant characteristic in the Spanish design because the
maximum crack width is lower. Moreover, the possible differences in the designs are almost evened
out after a fatigue verification for 120 years.