The main objective of this paper is to present the development of a Discrete Wavelet Transform (DWT)-based approach for quantifying aggregate segregation in asphalt concretes (AC). It implements this approach in analyzing the segregation of nine AC core X-Ray Computed Tomography (CT) images obtained through an automated digital image processing technique. It utilizes a DWT approach for separating coarse from fine aggregates, on the basisof a selected wavelength separating the two sizes. A segregation index (SI) is defined based on the wavelet energy in each group of aggregate particles. The SI was shown to be a high resolution numerical measure of aggregate segregation in the horizontal and vertical directions matching the perceived segregation obtained from the visual inspection of the images. Themean values of the SI along the horizontal and vertical directions give an overall measure of segregation in the sample along these directions.
Abstract