Acoustic Emission and damage monitoring in RC beams under cyclic loading

This paper proposes the results of Acoustic Emission (AE) measurements intended at investigating the structural response of two real-scale RC beams tested under four-point bending. Two different rebar configurations, with and without shear stirrups, were considered. Also, steel fibers are included in the concrete mixture. A loading procedure characterized by several cycles of increasing amplitude applied up to failure was implemented. Both AE and relevant mechanical parameters were continuously monitored during the whole test process. The failure behavior and the ability of various evaluation indices based on both structural and AE parameters to evaluate the damage level are presented and analyzed. AE rate exhibited good correlation with cracking initiation and evolution and, hence, they proved to be suitable for both monitoring the structural response and detecting eventual structural damage.