SIMORGH-SHM: A Novel Software for Fully Automated and Precise Fracture Monitoring Based on Acoustic Emission Localization and Moment Tensor Inversion

Passive ultrasonic stress wave, or acoustic Emission (AE), monitoring is a highly effective technique for continuously assessing the structural health of materials, aiding in the prevention of potential failures. AE refers to elastic waves generated during fracture processes, which are detected and recorded by ultrasonic transducers. Quantitative geophysics-based methods enable processing of recorded waveforms to monitor and characterize the spatio-temporal growth of fractures in brittle materials such as concrete and composites. Due to the complexity of the recorded elastic signals and the non-homogeneous nature of the medium, data processing is often performed manually. The high processing costs associated with large datasets, often exceeding terabytes, have limited the practical application of this approach in real-world scenarios. Therefore, an automated methodology is required to reduce costs while maintaining high precision, enabling its integration into Structural Health Monitoring (SHM) and Non-Destructive Evaluation (NDE) frameworks. This paper presents the application of a novel automated and high-precision AE monitoring algorithm and software, SIMORGH-SHM, designed for applications ranging from materials testing to seismicity. The software is compatible with various standard data formats and is capable of processing both trigger-based and continuous data streams. After introducing the software package, initial results from AE monitoring of a 4.2-meter-long Ultra-High-Performance Fiber-Reinforced Cementitious Composite (UHPFRC) T-beam are discussed. The beam was equipped with 24 novel embedded ultrasonic transducers and tested in EPFL's Structures Laboratory under cyclic loading to failure. Source localizations were performed and damage mechanisms were estimated using Moment Tensor Inversion (MTI) techniques.