Role of Asphalt Modification in Achieving Better Aggregate Packing Structure and Performance

Asphalt modifiers have been widely used to improve the engineering characteristics of asphalt mixtures. It has been commonly assumed that the main cause of this improvement is the change in binder rheological characteristics. Furthermore, use of modifiers has been known to affect compaction temperatures. However, what has not been considered in the past is the influence of asphalt modifiers on changing the aggregate structure of the mix during compaction. Recently, a number of studies using image analysis tools have shown that aggregate packing has a significant impact on mixture performance. In this study, an image analysis tool ("iPas2") has been used in combination with binder, mastic and mixture tests to study the effect of selecting a modifier and a combination of modifiers (elastomeric and plastomeric) on the Performance Grade (PG), as well as the effect on aggregate structure and performance for a number of mixtures compacted at different temperatures. The results allowed the identification of the relative importance of binder PG and aggregate skeleton changes on the high and low temperature response of asphalt mixtures. Results show that careful selection of modifiers can enhance performance of binders as well as aggregate structure when compaction is conducted at optimum temperatures. (A) For the covering abstract of this conference see ITRD record number 201402RT334E.

Language

  • English

Media Info

  • Pagination: p. 219-38
  • Monograph Title: Proceedings of the Fifty-Eighth Annual Conference of the Canadian Technical Asphalt Associatio (CTAA): St. John's, Newfoundland and Labrador, November 2013

Subject/Index Terms

Filing Info

  • Accession Number: 01518091
  • Record Type: Publication
  • Source Agency: Transportation Association of Canada (TAC)
  • Files: ITRD, TAC
  • Created Date: Mar 11 2014 11:01AM