Experimental Study on the Flexural Properties of FRP-Reinforced Super-Span Concrete T-Beam after Service

Abstract

Super-span (20 m) non-prestressed T-section reinforced concrete beams have been in service for more than 30 years and are common in Chinese highway bridges. However, the actual performance of these super-span T-section reinforced concrete (RC) beams that have been reinforced with FRP, including their process of failure from a service state to a failure state, has not been determined. In this study, original RC T-beams, with a 20 m span and retrofitted with FRP, were taken from a highway bridge. Their flexural performance was detected via experiments in a laboratory. The experiments revealed that the sectional strain distribution is more non-uniform. The mid-span ribs clearly play a role in strengthening the section and the bearing reservation was studied based on a subsequent sectional analysis. It became clear that the load-bearing reservation of an old super-span T-beam changes during the entire life of the specimen; not only because of the depression of the resistant capacity and the reinforced measure, but also due to the updates to load codes.