EFFECTS OF ASPHALTENES ON ASPHALT RECYCLING AND AGING (WITH DISCUSSION AND CLOSURE)
Blends made using n-hexane asphaltenes from asphalts, SHRP AAG-1, AAD-1, and AAK-2 and maltenes from SHRP AAG-1 and AAD-1 were laboratory-aged to study the effects of asphaltenes on rheological properties. For comparison, maltenes from SHRP AAG-1 and AAD-1 as well as their parent asphalts were aged at the same aging conditions as those of blends. The laboratory oxidation conditions were pure oxygen pressure at 20.7 bar absolute, temperatures of 71.1, 82.2, and 93.3 deg C with aging times from 1 to 24 days depending on aging temperature. The changes due to oxidative aging were monitored by asphaltene precipitation in n-hexane, Fourier transform infrared spectroscopy, and dynamic mechanical analysis at 60 deg C. Oxidative aging of asphalts and maltenes results in the formation of carbonyl compounds, the production of asphaltenes, and an increase in viscosity. The change in asphaltene content with respect to the change in carbonyl content is quantified by defining the asphaltene formation susceptibility (AFS). The type of asphaltenes, regardless of their sources, have no effect on AFS. Therefore, it appears that AFS is a strong function of maltene composition. However, the effect of asphaltenes on viscosity is only moderately dependent on the asphalt source of the asphaltenes. The results of this study show that the maltene composition has the dominant effect on the oxidation behavior of an asphalt. For recycling of road pavement, the results also suggest that a recycling agent should be chosen so that the mixture of the recycling agent and the maltene from the old pavement possesses good oxidation properties.
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Availability:
- Find a library where document is available. Order URL: http://worldcat.org/isbn/0309062012
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Supplemental Notes:
- This paper appears in Transportation Research Record No. 1507, Seal Coats and Asphalt Recycling. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved
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Authors:
- Lin, Moon-Sun
- Davison, Richard R
- Glover, Charles J
- Bullin, Jerry A
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Discussers:
- Robertson, Raymond E
- Branthaver, Jan F
- Petersen, J Claine
- HARNSBERGER, P M
- Publication Date: 1995
Language
- English
Media Info
- Features: Figures; References; Tables;
- Pagination: p. 86-95
- Monograph Title: Seal coats and asphalt recycling
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Serial:
- Transportation Research Record
- Issue Number: 1507
- Publisher: Transportation Research Board
- ISSN: 0361-1981
Subject/Index Terms
- TRT Terms: Aging (Materials); Asphalt pavements; Asphaltene; Oxidation; Recycling; Rheological properties; Viscosity
- Uncontrolled Terms: Maltenes
- Old TRIS Terms: Carbonyl content
- Subject Areas: Construction; Highways; Materials; I31: Bituminous Binders and Materials; I52: Construction of Pavements and Surfacings;
Filing Info
- Accession Number: 00715582
- Record Type: Publication
- ISBN: 0309062012
- Files: TRIS, TRB
- Created Date: Jan 5 1996 12:00AM