Automatic image analysis in evaluation of aggregate shape

The presented method of image analysis is aimed at the evaluation of aggregate grain shape for concrete mixes and other civil engineering purposes. Standard procedure of the aggregate shape evaluation (ASTM) involves manual, troublesome measurements and produces parameters that only roughly characterize the shape of aggregates. The present procedure enables automatic and accurate measurement of three main dimensions of each grain in a sample of aggregate grains, and makes possible evaluation of their flakiness and elongation indexes, as well as of the corresponding statistics. A new, more accurate method of the shape characterization of the samples of aggregates along with its graphical presentation is proposed. Examples of the application of the method to sets of aggregate grains of different origin demonstrate the effectiveness of the method and of the new shape characteristics.