Fatigue Tests of 27-Year-Old Prestressed Concrete Bridge Box Beams

Two precast, prestressed concrete box beams, 36 in. wide x 27 in. deep x 56 ft long (914 x 686 mm x 17.1 m), were removed from a deteriorated multibeam bridge and subjected to fatigue testing. Visually, the beams appeared in generally good condition but showed signs of water leaking through the longitudinal shear keys and some corrosion reinforcement. The beams were purposely precracked prior to fatigue loading and had periodic overloads applied.