Interrelation of morphological indices and 2-D generalized regularity for coarse aggregate in cement-based materials

A variety of indices are available to characterize the aggregate morphology, yet the resulting values are often considerably different, which can mislead the interpretation. This study aims to better understand the difference and interrelation of the five commonly accepted sphericities (global-form) and the roundness (local-angularity) for coarse aggregates. Several statistical methods including Principal Component Analysis are employed to quantify the degrees of correlation among the indices. In addition, Confirmatory Factor Analysis incorporated into the generalized regularity concept was proposed, demonstrating better discriminatory results than the conventional regularity concept. Furthermore, coarse aggregates of mixed sizes are utilized to demonstrate the efficiency of the proposed framework and the new regularity concept. (C) 2020 Elsevier Ltd. All rights reserved.