Title: Externally Bonded Composites for Strengthening Concrete T- Beam Bridges

Author(s): S. Morton

Publication: Symposium Paper

Volume: 188

Issue:

Appears on pages(s): 687-696

Keywords: bridges; carbon fiber; fiber reinforced polymers; highways; structures; thermography

DOI: 10.14359/5664

Date: 8/1/1999

Abstract:
This paper presents the results of laboratory testing of concrete beams and field testing of two concrete T-Beam bridges that were externally strengthened with CFRP. As a result of the lab testing all the systems tested showed a considerable increase of 68% for the ultimate strength and 45% decrease in deflection for the beams with 2-#4 reinforcing bars . The beams with 2-#7 reinforcing bars showed a 60% increase in ultimate strength and a 26 % decrease in deflection when comparing the loads that produced yielding of the steel in the baseline and the 5 layer test. Both structures were load tested and monitored before and after application of the CFRP with strain gages and LVDTs. The results showed an increase up to 8% in stiffness and up to 15% decrease in strain. In addition to the load test a quality assurance NDT evaluation was performed on the bond using infrared thermography. The results showed typically less than 2% voids between the CFRP and the concrete.