Recent developments in acoustic emission for better performance of structural materials

Acoustic emission (AE) is casually used for characterization of materials and structures. The damage mechanisms emit elastic signals with distinguishable characteristics allowing their identification as has been verified in all types of cementitious media, masonry, and polymer composites. Furthermore, the sensitivity of AE allows conclusions earlier than the moment of damage manifestation, providing therefore, early data in a structural health monitoring approach. Recently, AE was shown sensitive to the original strain field, allowing projections to the final damage. Results indicate monotonic relations between AE parameters and strain field even at small fractions of the ultimate load. This contributes to the real-time assessment of the material condition, before the load-bearing capacity is compromised, while being also promising for in-situ application. This study highlights the new trends showing the potential of using AE complemented with other techniques to adequately monitor and predict the behavior of structural materials.