Acoustic emission-based narrow-band partial power method to identify crack modes in a prestressed concrete viaduct

A new method has been proposed to analyze acoustic emission (AE) signals obtained from a prestressed concrete viaduct to realize the cracking mechanisms that evolve during the passage of trucks/cars. This new method exploits the information contained in narrow partial powers (PPs) bands of the acquired AE signals. The narrow PP bands are found to be extremely sensitive to the evolving damage modes in concrete, both in the case of in situ and laboratory experiments. Results show that the classification of trucks is possible using the cracking information contained in the narrow PP bands of the acquired AE signals during the passage of trucks. AE-monitored laboratory bending experiments have been performed on reinforced concrete T-beams. The effectiveness of the proposed narrow PP bands in the discrimination of damage modes in the beams is found to be overwhelming. The proposed method has a unique advantage in visualizing the frequency content of a large number of AE signals by using the narrow PP-based heatmap. This study consists of simultaneous measurement of strain and AE during the passage of trucks/cars, and correspondence between the two types of data has also been presented. This research work shows that frequency information of AE signals can be used for monitoring of prestressed/RC concrete structures.