EFFECT OF VOID DISTRIBUTION IN DAMAGED CONCRETE ON ACOUSTIC EMISION OF COMPRESSIVE STRESS FIELD

Abstract

In this paper, the void volume and void shape of damaged concrete were evaluated by X-ray CT. In addition, compressive strength tests with the AE method were conducted. The results show that the AE energy generation behavior differs depending on the void structure. In the case of the specimens with small void surface area, multiple AE energy peaks were observed and the failure proceeded in stages. On the other hand, for specimens with a large surface area of voids, the AE energy increased linearly and the failure progressed rapidly. It is clear that there is a positive correlation between void volume, void surface area and AE energy in the strain range from 0 to 100×10^-6. These results suggest that void distribution can be evaluated by focusing on the AE energy at the initial stage of loading in the compressive stress field.