Gradation optimization and strength mechanism of aggregate structure considering macroscopic and mesoscopic aggregate mechanical behaviour in porous asphalt mixture. (20th September 2021)

• Record Type: Journal Article
• Authors: Ren, Jiaolong; Xu, Yinshan; Huang, Jiandong; Wang, Yi; Jia, Zhirong
• Is Part Of: Construction & building materials. Volume 300(2021)
• Publication Date: 2021-09-20
• Subjects: Porous asphalt mixture -- Aggregate structure -- Gradation optimization -- Strength mechanism -- Macroscopic aggregate bearing capacity -- Mesoscopic aggregate contact force; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2021.124262
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: An optimized aggregate gradation of PAM based on aggregate bearing capacity. DEM numerical simulation of aggregate packing considering aggregate irregularity. Strength mechanisms of aggregate structure of PAM based on meso -contact-force. Abstract: Porous asphalt mixture (PAM) as a special pavement material with discontinuous gradation has been widely used in pavement engineering because of its versatility caused by high air void content. Aggregate structure plays a significant role in the pavement performance of porous asphalt mixture. In this study, the effects of different size aggregates on the air void ratio and macroscopic aggregate bearing capacity are investigated to put forward an aggregate gradation with a strong aggregate structure. Laboratory tests show that the proposed gradation provides an improved pavement performance for porous asphalt mixture. Moreover, strength mechanisms of aggregate structure in porous asphalt mixture are revealed from a view of the mesoscopic aggregate contact force composition using discrete element method (DEM) simulations considering aggregate irregularity. Finally, the mechanical role of each size aggregate on the aggregate structure is analyzed via mesoscopic aggregate contact force distribution.