Multi-level performance evaluation of BMD surface mixtures with conventional and high RAP contents: a case study in Virginia

ABSTRACT

This study investigated one control and five Balanced Mix Design (BMD) optimised asphalt surface mixtures, four of which had high reclaimed asphalt pavement (RAP) contents (HRAP mixtures), using laboratory performance tests characterised with different levels of complexity. The performance of the evaluated mixtures was assessed based on durability, rutting resistance, and cracking resistance as emphasized by BMD. The study explored the ranking of a single index and correlations among various indices. Assisted by 3-Dimensional and ternary plots, this study also proposed a novel composite performance index [CPI] that combines major indices (durability, cracking, and rutting) to evaluate the performance of BMD optimised mixtures. The results revealed discrepancies between basic/intermediate performance test results and advanced performance test results. The comparisons conducted also underscored the beneficial impacts derived from using softer binders and/or recycling agents in HRAP mixtures. Furthermore, the findings indicated that the BMD approach can serve as an effective framework for designing asphalt mixtures that simultaneously enhance both fatigue and rutting performance. Moreover, the study revealed HRAP BMD surface mixtures can exhibit superior overall performance when compared to conventionally designed control mixtures.

KEYWORDS:

• Reclaimed asphalt pavement
• high RAP
• asphalt concrete
• balanced mix design
• performance
• implementation
• accelerated pavement testing
• composite performance index
• recycling agents

Acknowledgments

The authors thank Andrew Barbour, Troy Deeds, Derek Lister, Danny Martinez Rodriguez, and Jennifer Samuels of VTRC; Donnie Dodds formerly of VTRC; Billy Hobbs of VTTI; and Wenjing Xue, Fabrizio Meroni, Max Ratcliffe, and Kenny Smith formerly of VTTI, for their outstanding efforts in sample collection and testing. Appreciation is also extended to Travis Higgs and Clyde Landreth of VDOT for their assistance and support. Sincere appreciation is expressed to Boxley Asphalt Paving and Ingevity for their contributions to this effort.

Author contribution statement

The authors confirm contribution to the paper as follows: study conception and design, data collection, analysis and interpretation of result, draft manuscript preparation: B. Tong, J. Habbouche, S.D. Diefenderfer, and G.W. Flintsch. All authors reviewed the results and approved the final version of the manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Disclaimer

The contents of this paper reflect the views of the authors, who are responsible for the facts and the accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of the Virginia Department of Transportation, the Commonwealth Transportation Board, or the Federal Highway Administration. This paper does not constitute a standard, specification, or regulation. Any inclusion of manufacturer names, trade names, or trademarks is for identification purposes only and is not to be considered an endorsement.

Additional information

Funding

This work was supported by Virginia Department of Transportation [grant number UPC 0000124200].