Experimental investigation on long term flexural performance of expansive concrete beams eccentrically reinforced by CFRP

Previous research has shown that unsymmetrical carbon fiber-reinforced polymer (CFRP) wrapped expansive concrete composite beams performed efficiently and effectively on delaying cracking and eliminating corrosion. However, it is crucial to explore the effect of self-prestressing on beams flexural performance after long-term prestress loss. In this research, fourteen composite beam specimens and four control specimens were designed. A series of tests, including material test, long-term static strain monitoring of beam specimens and four-point bending test, were conducted. Test results indicate that, in long-term, at the same layout of CFRP, SHCC specimens presented better performance than PCC on delaying cracking, controlling crack width of concrete and enhancing ultimate load capacity. The flexural capacity of the beam specimens increased with the increase of reinforcement ratio of CFRP. Furthermore, eccentric layout beam specimens presented superior performance than symmetric layout on the flexural behavior. It also indicated that the calculated results agree well with the experimental data, which can provide references for engineering practice.