Selection and use of unbound granular pavements with thin asphalt surfacing: 2017/18

Unbound granular pavements with thin asphalt surfacing (TAS-UB) are an economical pavement type for low to moderately trafficked roads in urban environments, or rural environments where sprayed seal surfacing does not meet the serviceability requirement. There is some anecdotal evidence that the fatigue life of TAS-UB is longer than predicted by the Austroads procedures. However, the actual life is unknown and has not been analysed. Some designers are reluctant to select this economical pavement type because of the very low asphalt fatigue lives predicted using the current Austroads pavement design procedure. To meet the current Austroads asphalt fatigue requirement, this often requires designers to select pavement solutions with significantly thicker asphalt layers. On the other hand, the thin asphalt surfacing option is sometimes selected because the asphalt fatigue life is ignored in the design process. The project will consider: actual performance of TAS-UB pavements and compare the field performance with the Austroads predictions; measures to improve performance, such as the need to select appropriate material properties for the asphalt surfacing and the supporting granular base layers. The aim of this project is to have a better understanding of the actual life of such pavements and provide guidance to designers which will lead to more appropriate selection of this pavement type.

Language

  • English

Media Info

  • Pagination: 476p

Subject/Index Terms

Filing Info

  • Accession Number: 01835472
  • Record Type: Publication
  • Source Agency: ARRB Group Limited
  • Report/Paper Numbers: P69
  • Files: ATRI
  • Created Date: Feb 7 2022 2:18PM