THE USE OF PROPANE-PRECIPITATED ASPHALT (PPA) IN BITUMINOUS PAVING MIXTURES (WITH DISCUSSION)
For a long time, but especially in the past decade, Propane-Precipitated Asphalt (PPA) has been used around the world as a component of asphalt cement as well as of cutbacks and emulsions at refineries where PPA was surplus. In these refineries, there is a constant striving for establishing the maximum proportions of PPA that can be incorporated in paving asphalt formulations. This paper summarizes the first part of a comprehensive research study on the use of asphalt cement containing PPA as a binder in bituminous paving mixtures. The research involved the testing of about 50 different samples of straight-run asphalt cements and PPA asphalt cement blends containing between 20% and 85% PPA in two- and three-component blendings. The testing programs involved an evaluation of the original rheological and physical properties as well as the long-term, age-hardening aging curves at different levels of temperature. Bituminous mixtures, involving durable and sensitive aggregates and different blendings of PPA asphalt cements, were evaluated by long-term hot-water immersion. Durability curves representing moisture-damage development were formed for immersion periods of up to 14 days. Test results were analyzed, using specific concepts and models developed for asphalt age-hardening and bituminous-mixture durability.
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Corporate Authors:
Association of Asphalt Paving Technologists (AAPT)
400 Selby Avenue, Suite I
St Paul, MN United States 55102 -
Authors:
- ISHAI, I
- Tuffour, Y A
- Conference:
- Publication Date: 1987
Language
- English
Media Info
- Features: Figures; References; Tables;
- Pagination: p. 599-631
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Serial:
- Volume: 56
Subject/Index Terms
- TRT Terms: Age hardening; Bituminous mixtures; Durability; Laboratory tests; Loss and damage; Moisture damage; Physical properties; Rheological properties; Water
- Old TRIS Terms: Hot-water immersion; Propane-precipitated asphalt
- Subject Areas: Highways; Materials; I31: Bituminous Binders and Materials;
Filing Info
- Accession Number: 00739811
- Record Type: Publication
- Files: TRIS
- Created Date: Aug 29 1997 12:00AM