Repairing Post-Tensioned Prestressed Concrete Bridge Girders with Frost-Heaving Damage

This case study proposed and evaluated an approach to repair post-tensioned prestressed concrete bridge girders in cold regions. The girders had severe frost-heaving cracks and unhardened cementitious grout in the prestressing ducts. Three full-scale girders were retrieved from a real highway bridge located in the Tibetan Plateau. The girders were repaired with two types of polymeric adhesives and evaluated through borehole and anatomy examinations and flexural tests after repairing. The results of the borehole and anatomy examinations of the damaged and repaired girders showed that polymeric adhesives filled the ducts and cracks. Flexural test results showed that the repairing significantly enhanced the load capacity, ductility, and crack resistance of the bridge girders. The mechanisms of the improvement in flexural properties due to the repairing are discussed. This research offers practical solutions and insights into the mechanisms for the repairing of post-tensioned prestressed concrete girders with frost-heaving damage.