Civil Engineering Association

This Design Guide provides all necessary information about the construction and static calculation of the superstructure of composite bridges for small and medium spans by using new innovative standard solutions.
The Design Guide includes all main topics concerning erection, construction details and the static analyses. Design charts are added to enable a fast forward pre-design. This report is based on the ECSC-Project “Composite bridge design for small and medium spans” which is shortly described later on. The results of the test programmes performed in this ECSCproject are summarised in standard solutions in this Design Guide. This Design Guide covers composite bridges with standard solutions by applying partially- and fully prefabricated slabs as well as solid slabs up to a span of 50 m. Furthermore a software has been developed to verify different kinds of constructions and enable a very fast static calculation by the practical engineer. Two examples of a single span bridge with fully prefabricated elements and a two span bridge with partially prefabricated slab are attached as tender documents including the static analyses by using the software and drawings with all details.

The research project was undertaken to develop and test new composite bridge concepts that are easily buildable by the best possible application of construction materials and a high grade of prefabrication. One of the problems was the use of hybrid girders which lead to significant material cost savings and to a reduction of girder heights. Therefore the fatigue rules given in ENV3 Part 2 have been validated experimentally and by numerical studies with a special regard to the local yielding of the web.
A further investigation were the use of dismountable shear connectors and headed studs with a diameter of 25 mm which are not considered in the codes until now. Studs with a diameter of 25 mm are favourable for bridges due to their higher shear resistance. This test series has included static and dynamic Push-Out tests.
Studies on the behaviour of joints of composite bridges took the special behaviour of partial and full prefabricated slabs into account. Reference bridges have been used to design the test set-up and cycle loadings were applied to simulate moving traffic loads. The investigations were performed in order to verify the opening of the joints, the fatigue behaviour

COMPOSITE BRIDGE DESIGN FOR SMALL AND MEDIUM SPANS