Integrity evaluation technology of PSC bridge tendons using acoustic emission technique

This paper deals with the evaluation of integrity using acoustic emission technique, one of the nondestructive inspection methods, for the safety diagnosis of structures constructed by prestressed concrete (PSC) method. The acoustic emission technique has excellent sensitivity characteristics, and it is possible to evaluate the degree of damage and the early defect diagnosis of large structures; thus, it is receiving interest as a technique for evaluating the integrity of concrete structures. We aim to monitor the breakage of the internal tendons of PSC bridges using acoustic emission technique and to evaluate the integrity of the tendons. The correlation between the Average frequency and RA value(rise time/amplitude) was analyzed as the acoustic emission parameters for the diagnosis. The RTRI(ratio of Repeated Train load at the onset of AE activity to Relative maximum load for the Inspection period) and improved b-value were applied to the acoustic emission analyzer to evaluate the presence of defects and integrity. Finally, in this study, it was confirmed that the PSC structure internal tendon can be evaluated by analyzing the acoustic emission characteristic signals generated by the PSC structure when load was applied to normal and defective tendons