New technical reports detail available materials for low to medium traffic roads

In recognising the shortage of quarried materials for road construction, Austroads has published two technical reports detailing fit-for-purpose materials for sealed and unsealed construction and maintenance of roads with low to medium traffic volumes.

In a statement Austroads said a fit-for-purpose material has properties and performance characteristics which suit a chosen design application.

These can be marginal or non-standard and may have been improved through mechanical or chemical stabilisation, or used in an operating condition which is not detrimental to its ongoing performance.

Ross Guppy, Austroads Program Manager Assets said there is an increasing shortage of quality quarried materials and natural gravels for road construction and maintenance. He said this comes with stricter legislation and land access requirements curbing the opening of new quarries and gravel pits.

“Gravel is also being transported over longer distances, increasing the costs of road construction and maintenance,” Mr. Guppy said.

When deciding if a material is fit-for-purpose, investigating the operating conditions affecting performance and then modifying the material, or design, construction or maintenance constraints to make it work can be a cost effective and sustainable solution.

Austroads commissioned a technical project to understand what influences material performance and to demonstrate how a material can be made fit-for-purpose within different operating conditions.

Tyrone Toole, co-author of the reports said Austroads developed two reports, one containing an evaluation and user guide and one containing the technical basis providing the evidence for the evaluation.

“Both reports include case studies that demonstrate how to assess the best use of available marginal and non‑standard materials on roads in various geographical and climatic Australian conditions,” Mr. Toole said.

Case studies in the reports also include examples of material assessment and option assessments in addition to life-cycle cost assessments for different scenarios.

The evaluation and user guide report contains guidance to help identify the most fit-for-purpose material.

The technical basis covers the justification for the information presented in the evaluation and user guide report.

Ross Guppy said he hopes outcomes from this project can significantly reduce the cost of road construction and maintenance for road operators, particularly in rural and remote areas on low-volume traffic roads.