Bituminous surfaced low cost road construction and maintenance in hot climates

This paper introduces some aspects of research carried out by the Australian Road Research Board (ARRB), in relation to the performance of mainly unbound granular road bases surfaced with either a thin layer of bituminous plant mix or a sprayed seal. This research is relevant to similar structures within the south east asian region. A desirable form of construction for the pavement of these low cost roads, methods of reducing the seasonal weakening in the outer wheelpath, the effect of heavy log haulage traffic on roads constructed for light traffic and a maintenance rating procedure (at present under development) are described. The relative merits of the two types of bituminous surface treatment are also discussed. In hot climate regions the bitumen in the surfacing hardens relatively rapidly and the yearly average of the maximum daily air temperature (YMMT) is a useful indicator of the relative amount of bitumen hardening which can be expected over a year. Once a certain level of hardness has been reached surface distress (cracking and fretting) will occur. The average of the daily minimum air temperature for the coldest month of the year (min mmat) is a useful indicator of the level of hardening at which distress will occur. This level decreases with the min mmat level. The ARRB has developed a laboratory test to assess the susceptibility of bitumen to hardening in service and this test is showing good correlation with field hardening. The test has recently been included in the Australian national specification for paving bitumens (a).

Language

  • English

Media Info

  • Pagination: 645-62
  • Monograph Title: Proceedings of the third conference of Road Engineering Association of Asia and Australasia. volume 1
  • Serial:
    • Volume: 1

Subject/Index Terms

Filing Info

  • Accession Number: 01438075
  • Record Type: Publication
  • Source Agency: ARRB
  • Files: ATRI
  • Created Date: Aug 24 2012 9:21PM