AE-SiGMA Code Approach to Detecting Concrete Damage Characteristics in Core Test

The mechanical properties of concrete are deteriorated by the development of cracks with a change in the stress-strain curve. In this study, concrete core samples were taken from in-service drainage gate with developed cracks. The geometrical properties of cracks and Acoustic Emission (AE) generation behavior under compressive stress field are investigated. AE is quantitatively evaluated by AE-SiGMA analysis, which evaluates the source location and its dynamic motion. In this study, the geometric properties of the cracks are visualized by X-ray Computed Tomography (X-ray CT) and the crack angle relative to the loading direction is quantified. As a result, AE events in the low frequency range are detected near vertical and diagonal cracks. AE events in the high frequency range are not detected same trend, which are located near horizontal cracks. It is presumed that this difference of the frequency range is due to the expansion of existing cracks and the propagation of cracks occurring depending on the crack angle. These results suggest that the crack propagation behavior under compressive stress changes according to the crack angle.