Durability of Hybrid Composite Beams

The number of bridges needing major rehabilitation and replacement is increasing along with their associated costs, so transportation agencies should consider their overall life cycle rather than initial investment alone. Cheaper materials susceptible to corrosion and other forms of deterioration can increase long-term maintenance costs. Materials and systems that allow faster assembly can reduce related traffic-control costs during construction and subsequent maintenance. Hybrid composite beams may be a viable alternative for some short- to medium-span bridges, especially where a lightweight superstructure or a shallow profile for vertical clearance is desired. However, the long-term performance of these beams needs to be analyzed. This study will employ accelerated laboratory and field exposure tests to evaluate the durability of the beams in brackish or marine environments. Routine and supplemental methods also will be developed for inspection of the structures.