![Sample our Engineering & Technology journals, sign in here to start your access, latest two full volumes FREE to you for 14 days]({"type":"image" , "src" : "/sda/5933/TOC-Subject-Sample-2021-Engineering-Tech.jpg"})
ABSTRACT
In this study, mixture design volumetrics, moisture-induced damage and fatigue characteristics of hybrid hot mix asphalt (HMA) fabricated with crumb rubber (CRM) and polyvinyl alcohol (PVA) fibre were evaluated. Indirect tensile strength test was conducted to assess several tensile and fracture attributes of control, polymer-modified, CRM-modified, PVA-reinforced and hybrid HMA. Long-term performance of aged hybrid HMA was also assessed using flexural beam fatigue test. Comparison of mixture designs indicated a change in volumetric properties of hybrid mixture with acceptable resistance to stripping. Experimental results revealed that fracture energy and dissipated creep-strain energy of the HMA with 2%CRM and 0.2%PVA doubled relative to polymer-modified HMA. The developed hybrid HMA presented around 29 times higher resistance to repeated load failure with 90% reduction in crack propagation rate and over 12 times higher energy for unit crack propagation compared to conventional HMA. Additionally, effective fibre bridging across the crack and adequate coating of asphalt on CRM through image analysis revealed wider strain distribution, a perverse intricate fracture pattern and better adhesion. The higher fracture resistance, toughness indices, and resilience under repetitive traffic loading of hybrid mixtures could be effective in extending the service-life and enhancing long-term performance of flexible pavements.
Acknowledgements
The authors would like to express sincere thanks to the University of Louisiana at Lafayette for providing the research facilities and funding. Authors acknowledge LT Lehigh Technologies for providing CRM, Kuraray Co. Ltd. for PVA fibres, Glenn Lege contractors for aggregates supply and BP Products North America for asphalt binder. Special thanks to Mark Leblanc and Dalen-Wigley Jones for their assistance in testing.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Author contributions
Muhammad Asghar: Research conception and outlining of the draft, laboratory testing and experimentation, data analysis and manuscript writing. Mohammad Khattak: Research conception, overall research supervision, feedback on analysis and review of the draft: Kayla Skye Fericy and Marco Manfra: Laboratory testing and experimentation, and data analysis. All authors reviewed and approved the final manuscript.