Acoustic emission from reinforced concrete beams

The acoustic emission behaviour of reinforced concrete beams under flexure load was studied. Useful correlation was established between the acoustic emission activity under loading state and crack growth in the reinforced concrete beams. Three different acoustic emission rate regions were observed during the flexural loading. Crack initiation and crack propagation were detected monitoring the acoustice mission. The zone ef crack initiation and development can be identified from the acoustic emission event-location plot, showing major acoustic emission concentration ureas. Repetitive loading showed that the Kaiser effect was valid only up to 80% of the ultimate load level, with norelaxation phenomenon , for test intervals less than 2h. Crack growth acoustic emission burst event signals were found to be of higher amplitude compared with those due to deformation. The accumulated number of burst events of these high-amplitude emissions, monitored by the use of a high threshold, showed good correlation with th...