01763535

Component

https://annualmeeting.myt...nlineProgram/Details/15549

Full-depth reclamation (FDR) is an in-place recycling process that uses the entire depth of deteriorated asphalt concrete (AC) pavement to produce a uniform stabilized base course and improve AC overlay performance. This paper introduces a mechanistic-empirical pavement design (MEPDG) methodology to determine the optimum thickness of an AC overlay over a stabilized FDR base course. The stabilized FDR mixtures had recycled asphalt pavement (RAP) blended with Portland Type I/II cement and/or Class C fly ash. The mixtures were evaluated using the standard Proctor, unconfined compressive strength (UCS), vacuum saturation, and linear shrinkage tests. The UCS test results were used as inputs in the MEPDG software to determine optimum AC overlay thickness. The test results indicate that the fly ash content impacts both optimum moisture content and shrinkage. Mixtures with only fly ash showed that higher fly ash content could significantly reduce shrinkage strain. The mixtures with 5% fly ash & 5% cement and 6% fly ash & 4% cement by weight of dry FDR material were found to meet the UCS required by the US Army Corps of Engineers (USACE). The MEPDG software results predicted that for the stabilized FDR mix with a UCS of about 250 psi (as required by USACE) or higher, the optimum AC layer thickness would be 3.5 in. for 10 to 12 in. stabilized FDR layer thickness.

This paper was sponsored by TRB committee AKP30 Standing Committee on Design and Rehabilitation of Asphalt Pavements.

TRBAM-21-02578

English

15p

2021

Transportation Research Board 100th Annual Meeting

Digital/other

Figures; Photos; References (13) ; Tables

Asphalt concrete pavements; Asphalt mixtures; Base course (Pavements); Fly ash; Pavement design; Pavement layers; Reclaimed asphalt pavements

Design; Highways; Pavements

Transportation Research Board Annual Meeting 2021 Paper #TRBAM-21-02578

TRIS, TRB, ATRI

Dec 23 2020 11:03AM