The Experiment Analysis of Bonding Performance between Near Surface Mounted CFRP Strip and Concrete at Different Curing Temperatures

Abstract

To investigate the bonding performance of near-surface mounted (NSM) carbon fiber-reinforced polymer (CFRP) technique under different curing temperatures, a total of five test specimens strengthened with NSM CFRP strip were tested by direct pull-out methods. The strain of CFRP strip, interfacial bonding shear stress, ultimate load and failure mode were analyzed through the test. The experiment results showed that the ultimate load and bonding shear stress of the specimens increased gradually when curing temperature was lower than the glass transition temperature (T _g) of the bond material. Afterward, they gradually decreased with the increase in temperature. The bonding shear stress was gradually transmitted from the loading end to the free end. The failure modes were changed from CFRP strip–adhesive interface bonding failure to CFRP strips fracture failure with the temperature rising. In this paper, the bonding performance experiment results of NSM CFRP strip could provide a reference for the rapid strengthening of monorail traffic track beams.

Keywords

NSM technique / Bonding performance / CFRP strip / Concrete / Curing temperature

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Funding

China railway corporation technology research and development plan(2016G002-L)

Beijing mass transit railway operation corporation research program(2016000501000005)