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Detecting prestressed wire breakage in concrete bridges is essential for ensuring safety and longevity and preventing catastrophic failures. This study proposes a novel approach for wire breakage detection using Mel‐frequency cepstral coefficients (MFCCs) and back‐propagation neural network (BPNN). Experimental data from two bridges in Italy were acquired to train and test the models. To overcome the limited availability of real‐world training data, data augmentation techniques were employed to increase the data set size, enhancing the capability of the models and preventing over‐fitting problems. The proposed method uses MFCCs to extract features from acoustic emission signals produced by wire breakage, which are then classified by the BPNN. The results show that the proposed method can detect and classify sound events effectively, demonstrating the promising potential of BPNN for real‐time monitoring and diagnosis of bridges. The significance of this work lies in its contribution to improving bridge safety and preventing catastrophic failures. The combination of MFCCs and BPNN offers a new approach to wire breakage detection, while the use of real‐world data and data augmentation techniques are significant contributions to overcoming the limited availability of training data. The proposed method has the potential to be a generalized and robust model for real‐time monitoring of bridges, ultimately leading to safer and longer‐lasting infrastructure. [ABSTRACT FROM AUTHOR]

• Fracto-emission signals (Acoustic, Electromagnetic, and Neutron Emissions) might be used as earthquake precursors. • The experimental results are analyzed by means of a suitable multi-modal statistics. • Fracto-emissions anticipate the seismic event with a chronologically ordered shifting. • An innovative interpretation of the earthquake preparation zone is proposed. • The relationship between low magnitude earthquakes and Moon phases is investigated. Fracto-emission signals (Acoustic Emission AE, Electromagnetic Emission EME, and Neutron Emission NE), triggered by high-frequency pressure waves at the different scales, can be used as a promising tool for environmental protection against seismicity. So far, no reliable method has been developed yet for the successful application of earthquake prediction because the physical mechanism of earthquakes and precursors is at present poorly understood, as well as the estimation of the so-called "earthquake preparation zone". On the other hand, recent studies are also re-evaluating the possible correlation between seismic activity and lunar periodicity. Since July 2013 an in-situ experimental campaign has started at a gypsum mine located in Northern Italy, revealing the strong seismic forecasting potentialities of the fracto-emission peaks by means of a dedicated monitoring platform and a multi-modal statistical analysis. In the present paper, an innovative interpretation of the earthquake preparation area is proposed, and the new experimental evidences obtained at the gypsum mine are reported confirming the previous results (Carpinteri and Borla, 2017). Finally, the relationship between small magnitude earthquake swarms occurred in the surroundings of the mine and the Moon phases is also investigated. [ABSTRACT FROM AUTHOR]

Three different forms of energy might be used as earthquake precursors for environmental protection against seismicity. At the tectonic scale, Acoustic Emission (AE) prevails, as well as Electro-Magnetic Emission (EME) at the intermediate scales, and Neutron Emission (NE) at the nano-scale. TeraHertz pressure waves are in fact produced at the last extremely small scale, and fracture experiments on natural rocks have recently demonstrated that these high-frequency waves are able to induce nuclear fission reactions with neutron and/or alpha particle emissions. Very important applications to earthquake precursors can be proposed. The authors present the results they are obtaining at a gypsum mine located in Northern Italy. In this mine, to avoid interference with human activities, the instrumental control units have been located at one hundred metres underground. The experimental results obtained from July 1st, 2013 to December 31, 2015 (five semesters) are analysed by means of a suitable multi-modal statistics. The experimental observations reveal a strong correlation between the three fracto-emission peaks (acoustic, electromagnetic, and neutron emissions) and the major earthquakes occurred in the surrounding areas. [ABSTRACT FROM AUTHOR]

Acoustic emissions (AE) due to microcracking in solid materials permit the monitoring of fracture processes and the study of failure dynamics. As an alternative method of integrity assessment, measurements of electrical resistance can be used as well. In the literature, however, many studies connect the notion of criticality with AE originating from the fracture, but not with the changes in the electrical properties of materials. In order to further investigate the possible critical behavior of fracture processes in rocks and cement-based materials, we apply natural time (NT) analysis to the time series of AE and resistance measurements, recorded during fracture experiments on cement mortar (CM) and Luserna stone (LS) specimens. The NT analysis indicates that criticality in terms of electrical resistance changes systematically precedes AE criticality for all investigated specimens. The observed greater unpredictability of the CM fracture behavior with respect to LS could be ascribed to the different degree of material homogeneity, since LS (heterogeneous material) expectedly offers more abundant and more easily identifiable fracture precursors than CM (homogenous material). Non-uniqueness of the critical point by varying the detection threshold of cracking events is apparently due to finite size effects which introduce deviations from the self-similarity. [ABSTRACT FROM AUTHOR]