Investigation of pavement design for low volume rural roads

Abstract

[Abstract]: This paper identifies a ‘best practice’ key criteria for Low Volume Rural Road pavements within Australia. The criteria have been established by comparing and critically evaluating existing practises undertaken by Local Government Authorities. The evaluation was undertaken after surveying numerous Councils across Australia focusing on their current practises relating to Low Volume Rural Road Pavements. A total of Fourteen Councils have been surveyed from Australia and the responses to the survey form the basis for concluding the results in relation to the Low Volume Rural Road pavements. Low Volume Rural Road pavements are pavements which cater for traffic volumes up to 200 vehicles per day. The pavement may be formed or unformed depending on its location and serviceability requirements. It may consist of various types of materials and may be sealed or unsealed depending on the situation. Materials and the pavement structure may consist of an earthen/in-situ material, a gravel layer with no seal, a gravel layer with a spray seal or a gravel layer with an asphalt wearing course. No single road pavement is identical to another as many variables influence the pavement structure and performance. Low Volume Rural Road pavements are presently designed, constructed and maintained with limited regard to reference material and accepted design guidelines. This is as a result of budgetary constraints and a misconception that the processes relating to a Low Volume Rural Road pavement can be undertaken with an ad-hoc approach as the pavement is not a critical asset. The reference material and guidelines relating to Low Volume Rural Road pavements are easily divided into separate key elements. This enables comparison and critical evaluation to be undertaken in terms of each element, to conclude an overall ‘best practice’ for the pavement system in its entirety. Recommendations for further research into some of these design elements are presented due to conflicting information in the publications reviewed or a lack of information. A ‘best practice’ key criteria guideline has been concluded. It shares many similarities to some of the existing design guidelines, giving it some merit. Field testing, and practical application is recommended to research its effectiveness.