Flexural behavior of RC beams enhanced with carbon textile and fiber reinforced concrete

Abstract

Concrete cracking is the major cause of steel corrosion and performance degradation of reinforced concrete (RC) members. To significantly enhance the crack resistance and flexural performance of RC beams, textile and fiber-reinforced concrete (FRC) were used in this study, and a simple anchoring method of textile was proposed to prevent debonding failure. Eight RC beams were designed and tested, and the test variables included carbon textile, anchoring method and pouring thickness of FRC. The test results revealed that the proposed anchoring method can effectively avoid the debonding phenomenon; both carbon textile and FRC can improve the crack resistance, improve the flexural capacity and reduce the damage of specimens. Among, the combination of carbon textile and FRC is the most effective method to improve the mechanical properties of specimens. Compared with the ordinary RC beam, the crack resistance and flexural capacity of textile-FRC composite beams can be increased by 79.56% and 39.04% respectively under specific conditions. With the increase of the pouring thickness of FRC, the mechanical properties of the specimens gradually enhanced, while the growth rate gradually slowed down. Through sectional analysis, the calculation methods of the load-midspan deflection curve and flexural capacity of textile-FRC composite beams were established. The accuracy and applicability of the calculation methods were verified by test and finite element analysis. In addition, theoretical calculation results show that the enhancing effect is not significant in the case that the pouring thickness of FRC is beyond 64% of the section height.