Acoustic emission imaging of shear failure in large reinforced concrete structures

In this study acoustic emission (AE) techniques were employed to investigate the process of fracture formation in large, shear-critical, reinforced concrete beams and to gain improved insight into the mechanisms of shear failure. Large sensor arrays were specially designed to study various aspects of failure by observing the fracturing processes throughout the load history of the beams. Smaller, more concentrated sensor arrays revealed complex spatial and temporal fracture development at the slow quasi-static and spontaneous dynamic stages of propagation. When AE events are related to the micro-structure of concrete through computed tomography images and surface fracture measurements they show that coarse aggregates play important roles in shear fracture propagation in reinforced concrete.