Comprehensive evaluation of the long-term performance of rubberized pavement, phase II : the influence of rubber and asphalt interaction on mixture durability.

Details

• Creators:
  Shen, Junan ; Xie, Zhaoxing ; Li, Bo
• Corporate Creators:
  Georgia Southern University
• Corporate Contributors:
  United States. Federal Highway Administration
• Subject/TRT Terms:
  • Hot mix asphalt
  • Asphalt mixtures
  • Crumb rubber
  • Laboratory tests
  • Dynamic modulus of elasticity
  • Fatigue (Mechanics)
  • Rutting
  • Bituminous binders
  • Weathering
  • Pavement performance
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• Publication/ Report Number:
  FHWA-GA-12-1229
• Resource Type:
  Tech Report
• Geographical Coverage:
  Georgia
• Corporate Publisher:
  Georgia. Department of Transportation. Office of Research
• Abstract:
  This project investigated the long-term performance of hot asphalt mixes containing crumb rubber ; modifiers (CRM) added in dry or wet processes. A total of eight asphalt mixtures—four Porous ; European Mixtures (PEMs) and four Stone Matrix Asphalts (SMAs)—were designed with PG 76-22 ; modified with CRM, which was added in either a dry or wet process. These mixtures were compared to ; control mixtures using an SBS-modified PG 76-22. Mixtures incorporating a “hybrid”-modified PG ; 76-22 were also evaluated. First, the samples were weathered in the Georgia Weathering Asphalt Device ; (GWAD) for 1,000 hrs and 3,000 hrs and tested to determine their dynamic modulus, fatigue life, ; rutting, and Cantabro. Binders extracted from the weathered samples were then evaluated using a ; dynamic shear rheometer (DSR), gel-permeable chromatography (GPC), and Fourier transform infrared ; spectroscopy (FTIR). Second, the interactions of dry- and wet-processed CRM with asphalt binder were ; compared during storage and paving. Results indicated: 1) adding TOR to the CRM binder improved ; PG grade and separation resistance; 2) the dynamic modulus, |E*|, of both rubberized PEM and SMA in ; dry process did not differ significantly from that of the control mixtures or mixtures using the “hybrid”- ; modified binders before and after weathering; 3) the fatigue life (Nf) of unaged rubberized PEM and ; SMA in the dry process was similar to that in wet process, although lower than that of control SBS; 4) ; after 3000-hrs aging, the fatigue life of the dry-processed rubberized SMA is similar to that of the ; wet-processed but lower than that of hybrid and SBS SMA, regardless of strain and stress levels or test ; temperatures; 5) the rutting and Cantabro loss of the rubberized PEM and SMA in dry process were ; higher than those of control SBS after weathering; 6) CRM and asphalt binder interact during the ; production and paving stages based on DSR, GPC, FTIR, and AFM results. The effect of weathering on ; the properties of the asphalt binders in rubberized, dry-processed PEMs and SMAs was similar to that in ; the wet-processed mixtures but greater than that in the control SBS.
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• Format:
  PDF
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/29368/dot_29368_DS1.pdf
• File Type:
  [PDF - 6.92 MB]
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha-512:4983eb751e592daaf755552c8b7756565de025f2d79ecf0bb3f4a776eec285c9fb84c4166cf67bc899ec7279b6e083aa267957a242ff805cf1f9b12f6b1cf132