AN INVESTIGATION INTO THE EFFECT OF THE PROPORTION OF RECLAIMED ASPHALT ON SOME ASPECTS OF THE QUALITY OF RECYCLED MIXES

Recent work has provided a model to relate the expected savings to the circumstances under which recycling is done and has offered an economic evaluation method for relating these to fears about the quality of the recycled mix. Although such an analysis can be based on subjective opinion of the quality, its relevance will be much enhanced by empirical data. This paper describes the results of the first phase in a programme of work designed to provide such data. It identifies the factors possibly causing recycled mixes to have poorer quality than conventional mixes as being those relating to the difficulty in controlling the composition of the mix and those relating to any inferior properties of the reclaimed weathered binder. It is to the latter question that this phase of work is being addressed. It is also noted that different properties are required depending on whether the mix is to be used for surfacing or base layers. An experiment was carried out to test the initial engineering properties of mixes composed of different proportions of reclaimed material yet meeting the design criteria of conventional mixes. These properties, fatigue and deformation resistance under conditions relating to base layers, were also compared with those of conventional mixes. The results show no decrease in quality with increased proportion of recycled material. Preparation of the mixes for testing was facilitated by a mini recycling plant. (TRRL)

• Corporate Authors:

  National Institute for Transport & Rd Res S Af

  P.O. Box 395
  Pretoria 0001, Transvaal,   South Africa 
• Authors:
  • Servas, V P
  • Ferreira, M A
  • Curtayne, P C
  • Viljoen, A W
• Publication Date: 1984-10

Media Info

• Features: Figures; References; Tables;
• Pagination: 49 p.
• Serial:
  • NITRR Technical Report
  • Publisher: National Institute for Transport & Rd Res S Af

Subject/Index Terms

• TRT Terms: Binders; Bituminous mixtures; Deformation; Fatigue (Mechanics); Mix design; Properties of materials; Quality control; Recycled materials; Testing
• Uncontrolled Terms: Quality
• ITRD Terms: 4948: Binder; 4967: Bituminous mixture; 5595: Deformation; 5579: Fatigue (mater); 4714: Mix design; 3648: Mixing plant; 9063: Quality; 4573: Recycling (mater); 2961: Roadbase; 5544: Strength (mater); 2972: Surfacing; 6255: Test; 5281: Weathering
• Subject Areas: Highways; Materials;

Filing Info

• Accession Number: 00471256
• Record Type: Publication
• Source Agency: Transport Research Laboratory
• Report/Paper Numbers: RC/12/84
• Files: ITRD, TRIS, ATRI
• Created Date: Jun 30 1987 12:00AM