Abstract:The mesoscale morphology characteristics of coarse aggregates in concrete have an important influence on its macroscopic mechanical properties. Based on the XCT (X-ray Computed Tomography) scanning images of a concrete cube specimen with a side length of 20 mm, the two-dimensional mesoscale morphology characteristics of the aggregates were studied through two aspects: the regularity and convexity. The results show that the aspect ratio, the ellipse similarity, and the angularity can be selected to effectively characterize the two-dimensional morphological characteristics of the coarse aggregates; according to the statistical analysis of morphological indicators of a large number of aggregates, it is found that the aspect ratio, the ellipse similarity, and the angularity are mainly located in the areas of (1,3), (0.8,1) and (1,1.1) respectively, and they are in the relationship of quadratic polynomial distribution. The research results can provide a fundamental reference for the research on the three-dimensional morphology characterization of coarse aggregates in concrete.