An experimental study on retrofitted fiber-reinforced concrete beams using acoustic emission

Fiber Reinforced Polymer (FRP) sheets are becoming increasingly important as a structural repair method when the load carrying capacity of deteriorated concrete beams is judged to be inadequate. In this field, the repair process must successfully integrate new materials with the old ones, forming a composite system capable of enduring exposure to service loads, environment and time. In this work, a set of Fiber Reinforced Concrete (FRC) beams has been retrofitted with fiber-reinforced polymer (FRP) sheets in order to improve their loading carrying capacity. These beams have been tested up to failure under three-point bending. During the loading tests, the acoustic emission AE technique has been applied to evaluate the damage evolution. By identifying the complete shape of the signals, the three-dimensional locations of damage sources are determined from the AE sensor records. In this connection, the authors have tuned an original procedure using advanced techniques that are usually applied for the analysis of seismic events.