Fatigue is the progressive and irreversible change of the internal material structure due to repeated cyclic loading. These cyclic loads can result from wind, waves, temperature fluctuations, and traffic loads. Each load cycle introduces micro-damages that accumulate and eventually lead…
Fatigue is the progressive and irreversible change of the internal material structure due to repeated cyclic loading. These cyclic loads can result from wind, waves, temperature fluctuations, and traffic loads. Each load cycle introduces micro-damages that accumulate and eventually lead to failure. Detecting these micro-damages requires the use of sensitive measurement techniques. This is where advanced non-destructive testing (NDT) methods, such as acoustic emission (AE) and digital image correlation (DIC), play a vital role. Cylindrical mortar samples are subjected to a cyclic Brazilian splitting test. During the cyclic load, the damage evolution is monitored with AET and DIC. The progression of damage, measured through the cumulative count of acoustic emission events exhibited a strong correlation with the tensile deformation measurement obtained from Digital Image Correlation (DIC). The damaged region visualized with both techniques corresponds well. Subsequently, the size of the FPZ is measured using several AE-based and DIC-based methods. A comparison of the approaches indicated that the AE energy-based method is the most suitable to quantify the FPZ size during fatigue damage progress.