Advanced Acoustic Emission-based SHM for Concrete Structures: Real-Time, High-Precision Imaging of Crack Geometry and Damage Source-type Using Moment Tensor Inversion

In this paper, we introduce a novel automated and high-precision acoustic emission (AE) monitoring algorithm and the software SIMORGH, which is suitable for structural health monitoring (SHM) of civil structures. Initially developed for laboratory-scale hydraulic fracture monitoring, this core software has been effectively scaled up to meter-level applications and is compatible with heterogeneous media such as concrete. It is designed to work with various standard data formats and is handles both trigger-based and continuous data. We present initial results from implementing this software in the AE monitoring of two 4.88-meter-long concrete beams in a laboratory setting, comparing it with manually processed AE data. Our approach enabled the identification of over three times more AE sources than manual processing, achieving higher precision. By processing waveform features in both the time and frequency domains, we successfully classified the damage sources into three categories: tensile, shear, and mixed-mode, at different stages of the experiment. With adequate processing units, the software can operate in parallel, facilitating real-time SHM with exceptional precision in imaging both crack geometry and source types. This involves the incorporation of moment tensor inversion (MTI) to further characterize the physics of AE sources, thereby providing invaluable information to decision-makers regarding the nature of the data captured in real-time.