Study on Full-scale Bending Experiment of Concrete Girder Reinforced by Steel Plate and Concrete Composite Strengthening Method

Concrete bridges often have damages after opening to traffic for several years, it is necessary to reinforce the bridges in order to ensure the safety and extend the service life of the bridges. The steel plate and concrete composite strengthening (SPCCS) is a new retrofit technique, it works through welding studs on the reinforcing steel plates, planting steel bars in the original concrete, and casting concrete between the original structure and the steel plates, thus the new and existing concrete can work together. The strengthened structure has the advantages of high bearing capacity, large stiffness and long term durability. In order to investigate the mechanical performance of the strengthened bridge, a full-scale damaged box girder released from an actual bridge was reinforced by SPCCS technique. The bending resistance test was carried out and the test results were analyzed in this article. On the basis of the test, the SPCCS technique was applied to reinforce a damaged bridge. From the field test data, it showed that the bend resistance of the bridge was increased a lot after reinforcement. The SPCCS technique is an effective method to reinforce the concrete bridge, which can help realizing the sustainable maintenance of the bridge.