Abstract:Glass fiber reinforced plastics (GFRP) has been widely used in many industrial fields. However, there are still many problems to be solved in acoustic emission (AE) dynamic monitoring of the composites. A focusing enhancement technique with virtual loading based on time reversal theoryis proposed forthe strong anisotropy of GFRP, which can be applied to locate thesoundsource. First, thetheoreticalmodelof signalfocusing enhancementtechniqueinthe process ofvirtual loading is derivedaccording to the principleof timereversal.Then, the sensor array are arranged on GFRP, and the sound velocity is measured at different positions in the monitoring area for obtaining the material average sound velocity 2 43232 m/s. Finally, the simulated AE signals collected in experiment are processed by the proposed model The vibration amplitude of each pixel in the monitoring area is calculated and fluctuation image is reconstructed. The position of the AE source is determined by the maximum amplitude. After threshold processing, the location of AE source can be seen intuitively from the figure. Compared with the existing AE instrument, experimental results show that this method has positioning accuracy within 4%, which can meet the requirements of engineering application.