The equivalent heavy vehicle concept in Australian sprayed seal design.

The foremost challenge facing Australian spray seal designers is the performance of sprayed seals under the increasing numbers of large heavy vehicles on major transportation routes connecting capital cities and in rural areas of New South Wales, Queensland and Western Australia. It is expected that the Australian freight task will increase by 25 per cent between 2000 and 2010, with most of this increase already occurring. Based on data collected in rural areas, the traffic adjustment for heavy vehicles was amended in the 2006 update of the Austroads sprayed seal design method. This paper discusses the investigation currently being conducted into the effect of these large heavy vehicles on sprayed seals, and the concept and development of equivalent heavy vehicles introduced in the Australian design method in 2006. This paper describes the next steps in rationalising this concept. (a) For the covering entry of this conference, please see ITRD abstract no. E217100.