Damage monitoring of masonry structures using the acoustic emission technique - From tensile and shear characterization tests to shear wall tests

This study evaluated the ability of the acoustic emission technique (AET) to monitor the mechanical damage in masonry structures through multiscale experimental tests ranging from the mesoscopic scale (unit-mortar-unit samples) to the macroscopic scale (shear wall). At the mesoscopic scale, the AET was applied to a series of stone-assembly laboratory specimens subjected to tensile and shear loading. Initially, a mechanical analysis was conducted to characterize two types of cracking, namely mode I (tensile) and mode II (shear). Various acoustic emission (AE) parameters were analyzed in relation to damage accumulation to understand their responses to each type of loading. The representation of AE amplitude versus duration was distinctive in discriminating signals originating from different sources. To validate these findings on the macroscopic scale, we conducted a full-scale test for a shear wall subjected to compression, using both the AET and digital image correlation (DIC). Compared with the DIC results, AET demonstrated a strong performance in damage evaluation and source distinguishment of damage in masonry at the macroscopic scale, which involves more complex failure mechanisms.