Nondestructive evaluation on damage of carbon fiber sheet reinforced concrete

In recent years, carbon fiber sheet (CFS) has been widely used for reinforcement and rehabilitation of damaged concrete beams. However, the fundamental mechanisms of load transfer and load-resistance for CFS reinforced concrete are not fully understood. In this study, a three-point bend test has been carried out to understand the damage progress and the micro-failure mechanism of CFS reinforced concretes. For these purposes, four kinds of specimens were used: unreinforced concrete, steel bar reinforced concrete, CFS reinforced concrete, and concrete reinforced by both steel bar and CFS. Acoustic emission (AE) technique was used to evaluate the characteristics of damage progress and the failure mechanism of the specimens. In addition, two-dimensional AE source location was also performed to monitor crack initiation and propagation processes for the four specimen types. Keywords