Mechanics Research Communications, Volume 47, January 2013, Pages 39-43.
D.G. Aggelis, A.C. Mpalaskas, T.E. Matikas.
Department of Mechanics of Materials and Constructions, Free University of Brussels, Pleinlaan 2, 1050 Brussels, Belgium &
Department of Materials Science and Engineering, University of Ioannina, Ioannina 45110, Greece
Abstract
The present study deals with the examination of the acoustic emission signatures of distinct fracture modes. Tensile and mixed mode cracking is excited in specimens of marble and cement mortar and the acoustic emission behavior is monitored. Tensile cracking incidents show a preference to higher frequencies and shorter waveforms unlike shear events. The results imply that adequate analysis of simple AE features enables the characterization of the current fracture condition of the material and consequently predictions on the remaining safe service life for monolithic, as well as microstructured materials.
Additional information:
This research project has been co-financed by the European Union (European Regional Development Fund – ERDF) and Greek national funds through the Operational Program “THESSALY MAINLAND GREECE AND EPIRUS-2007-2013” of the National Strategic Reference Framework (NSRF 2007-2013).
Fig. 1. (a) Three point bending test of mortar and (b) shear test of marble with concurrent AE monitoring by two sensors.
Fig. 2. Peak frequencies for bending and shearing events as recorded by the sensor at 15 mm away from the cracking zone. The symbols stand for the PF of the corresponding events, while the solid lines for the moving average of five points.