The study of the effect of internal structure on permeability of porous asphalt. Issue 4 (19th May 2018)

• Record Type: Journal Article
• Authors: Król, Jan B.; Khan, Rawid; Collop, Andrew C.
• Is Part Of: Road materials and pavement design. Volume 19:Issue 4(2018)
• Page Start: 935
• Page End: 951
• Publication Date: 2018-05-19
• Subjects: porous asphalt -- X-ray CT -- internal structure -- image analysis -- permeability -- statistical analysis; Road materials -- Periodicals; Highway engineering -- Periodicals; Pavements -- Design and construction -- Periodicals; 625.805
• DOI: 10.1080/14680629.2017.1283355
• Languages: English
• ISSNs: 1468-0629

Abstract

Abstract : X-ray computed tomography (CT) and laboratory permeability techniques were applied to study the internal properties of porous asphalt mixture. Specimens containing aggregate of different gradations and of different mineral compositions were prepared in the laboratory. The air voids of all the specimens were determined in the laboratory and the specimens were then scanned in X-ray CT. The same samples were then tested for laboratory permeability. The active air voids and contact points of aggregate with nearby aggregate particles were determined from X-ray CT images. The laboratory permeability test results were found in comparison with X-ray CT values of voids' internal connectivity. A comparatively high permeability value was observed for porous asphalt with maximum aggregate size irrespective of its mineral composition. The size of air voids and volume of active (connected) air voids were also found high for mixtures made up of large aggregate size. The difference in mineral composition of aggregate was found to have considerably less effect on permeability of porous asphalt.