Composite Structural Members for Short Span Highway Bridges

This research focused on the development of a structural system composed of a reinforced concrete (RC) deck and fiber reinforced plastic (FRP) girders and arches. The deck and the girders were designed to carry the load by means of composite action. This system can be used in applications such as short span bridges. The research study involved both experimental and analytical work.

In all, six full-scale specimens were tested. Each specimen was composed of an RC deck and an FRP component, i.e. girder, arches. The length of each specimen was 30 ft, with a clear span between supports of 28.5 ft. The RC deck had an average width of 4 ft., and a thickness of 6 in. Both short and long term loading was considered.

Pultruded and contact molded FRP girders were utilized. A pair of arches assembled with filament wound FRP pipes also was studied as an alternative to the girders.

Based on the experimental results, the structural system proposed was found to be suitable for short span bridge applications. Furthermore, the excellent corrosion resistance of the FRP makes this system ideal for applications in corrosive environments.

Finally, the experimental data was used to develop design recommendations for the proposed structural system.