A comparative study on the implementation of carbon and glass fibers wrappings to improve the compressive strength and seismic behavior of concrete

Fiber-reinforced polymer (FRP) wrapping is one of the current approaches for retrofitting projects. This study aims to compare the performance of carbon and glass fibers in increase of compressive strength and improvement of concrete seismic parameters. In this research, three classes of concrete compressive strength (20, 35, and 50 MPa) are considered. The samples are warped with 0, 1, 3, and 5 layers of both fibers and examined under stress–strain tests. The results show that by adding more FRP layers, an increase is seen in compressive strength and seismic parameters. However, their growth rates decline. Moreover, the effect of both types of fibers is greater on improvement of compressive strength and failure strain for higher strength concrete. In contrast, fibers are more influential on lower strength concrete regarding energy absorption and ductility. Carbon and glass fibers are more effective in enhancing of compressive strength and seismic parameters, respectively. Statistical analysis indicates that, by adding more FRP layers, a tangible improvement on compressive strength and seismic parameters of concrete can be observed. That is true, especially for lower strength concrete. Moreover, the results demonstrate that the effect of fibers on the mentioned quantities is generally more than the effect of concrete classes. Finally, the Lam & Teng model shows a good fit with the experimental stress–strain diagrams.