Asphalt Internal Structure Characterization with X-Ray Computed Tomography and Digital Image Processing

Abstract

Abstract. In this paper, detailed study is carried out to develop a new workflow from image acquisition to numerical simulation for the asphalt concrete microstructures. High resolution computed tomography scanned images are acquired and the image quality is improved using digital image processing techniques. Nonuniform illumination is corrected by applying an illumination profile to correct the background and flat-fields in the image. Distance map based watershed segmentation are used to segment the phases and separate the aggregates. Quantitative analysis of the micro-structure is used to determine the phase volumetric relationship and aggregates characteristics. The result of the quantitative analysis showed a very high level of reliability. Finite Element simulations were carried out with the developed micro-mechanical meshes to capture the strength and deformation mechanisms of the asphalt concrete micro-structure. From the micro-mechanical investigation the load transfer chains, higher strength characteristics and high stress localization at the mastic interface between adjacent aggregates was shown.

On the oxidative ageing mechanism and its effect on asphalt mixtures morphology

“…The X-ray scanning process includes sample preparation, pre-scan settings, scanning, detector calibration and CT calibration. Detailed information of the scanning process and digital image processing for asphalt cores can be found in [14].…”

Energy-based damage and fracture framework for viscoelastic asphalt concrete

“…viscoelastic medium [44,45]. However, as has been shown in several micromechanical studies, the mechanical properties of the asphalt mixture's constituents, the variation in the shape and size of voids as well as the spatial distribution of the voids inside the asphalt mixture limits the use of the principles of fracture mechanics for the description of fracture initiation in asphalt concrete mixtures (e.g., [30,34,48]). …”

A study on characteristics evaluation to control quality of asphalt mixture using X-ray CT

“…Zelelew and Papagiannakis (2011) presented volumetrics-based thresholding algorithm using grey-level histogram to divide CT image of asphalt concrete into three phases: void, mastic, and aggregate. Coleri, Harvey, Yang, and Boone (2012) presented a new approach to clarify rutting mechanisms using a heavy vehicle simulator and X-ray CT. Onifade, Jelagin, Guarin, and Birgisson (2013) clarified the asphalt internal structure using X-ray CT, digital image processing, and micromechanical finite element analysis. Zelelew, Almuntashri, Agaian, and Papagiannakis (2013) compared two threshold models such as the adaptive enhanced-based thresholding algorithm and the watershed segmentation embedded into the volumetrics-based thresholding algorithm for asphalt concrete X-ray CT images.…”