Design of foamed bitumen pavements

Foamed bitumen is currently receiving special attention as virgin aggregates become less readily available. Foamed bitumen technology enables pavement layer(s) to be recycled and used as a stabilised base with the addition of foamed bitumen. While the cost of foamed bitumen is still relatively high at present, the technology offers a number of advantages other than material conservation. These include better durability and performance compared to unmodified granular material. On the other hand, the behaviour of foamed bitumen is rather complex and, as affected by its composition; it may not always produce the expected performance. This paper discusses the behaviour of foamed bitumen stabilised base which may show three stages of life: the initial stage, the bound stage and the unbound stage. The design of a pavement containing this material will thus have to consider these three stages. The initial stage is often predicted by performing laboratory testing on laboratory prepared specimens or on specimens cored from the field. While these specimens may give initial moduli for determining the minimum pavement thickness, it is shown herein that the field performance will vary with the environment and loading conditions so that there is a possibility that foamed bitumen may need one year to develop its full strength. This paper describes the design methodology for foamed bitumen stabilised pavements based on the interim Australian method and further suggests that design reliability may be improved by treating the foamed bitumen stabilised layer as a granular layer for at least the first six months of trafficking.

• Authors:
  • Nataatmadja, A
  • Anwar, S
• Conference:
  • RTA Pavements Conference, 2011, Sydney, New South Wales, Australia
• Publication Date: 2011-9

Language

• English

Media Info

• Pagination: 11p (day 1)
• Monograph Title: RTA Pavements 2011 Conference, 20-21 September 2011, Darling Harbour, Sydney

Subject/Index Terms

• TRT Terms: Granular soils; Pavement design; Pavement layers; Properties of materials; Reliability
• Uncontrolled Terms: Foam bitumen; Pavement technology
• ATRI Terms: Foamed bitumen; Granular; Material properties; Pavement design; Pavement layer; Reliability
• ITRD Terms: 4974: Foamed bitumen; 4573: Recycling (mater); 3688: Roadbase stabilization
• Subject Areas: Highways; Pavements; I22: Design of Pavements, Railways and Guideways;

Filing Info

• Accession Number: 01374098
• Record Type: Publication
• Source Agency: ARRB
• Files: ITRD, ATRI
• Created Date: Jun 27 2012 9:55AM