Damage Processes of Steel Fiber Reinforced Mortar in Different Fiber Content Revealed by Acoustic Emission Behavior

Аннотация

The performance of the cement-based materials could be improved by the incorporation of steel fiber, but the damage processes become more complex with different content at the same time. The acoustic emission (AE) technology can achieve the global monitoring of internal damage in materials. Under the axial compression load, the AE signals of steel fiber reinforced mortar specimens with different fiber content during the whole damage process were selected. The analysis of the damage evolution process, failure mode and damage degree were conducted by AE energy, RA value, AF value and b value respectively. It is found that the cement matrix cracked on the initial stage, the cracks further developed in the medium stage as well the fiber out of shape and the fiber were pullout on the last stage. The cumulative AE energy is proportional to the ductility of the material. The damage mode and damage degree can be judged by identifying the damage stage which obtained by the analysis of the AF value. It conducted that AE parameters can describe the failure processes due to it change monotonically with the progress of damage.