Όνομα Συνεδρίου:8th International Conference on Fracture Mechanics of Concrete and Concrete Structures, FraMCoS 2013
Three-point bending tests were performed on cement mortar beams of rectangular cross section. The specimens were subjected to abrupt compressive step loading while simultaneous Acoustic and Electrical Signal Emissions were recorded. In order to evaluate the development of the fracture process, characteristics of acoustic emissions and electrical current signals were studied and compared by isolating specific time frames that correspond to every step up to the fracture. In terms of time series cumulative energy of Pressure Stimulated Currents (PSC) and Acoustic Emissions (AE) were compared. Moreover, cumulative frequency distribution (Gutenberg-Richter relationship) and b-value analysis was performed in the AE using Gutenberg-Richter and Aki's methods. The objective of the experiments was to study the variation of AE based b-value with respect to time. It was observed that the AE based b-value analysis serves as a tool to identify the development of cracks and assess damage evolution.