Road base rehabilitation using foam bitumen asphalt

Project background

The City of Whittlesea used a foam bitumen asphalt base course made from 95.3% of recycled materials to rehabilitate an area of failed pavement within Yale Drive, Epping. The recycled materials include road base with waste glass, sand and aggregates. The use of foam bitumen asphalt as a cold asphalt alternative to stabilise road bases is common and has been utilised within the City of Whittlesea historically. However, it is the first time bitumen asphalt has been produced with recycled glass materials within the council and Victoria.

This new technology reduces the need for virgin materials and enables the increased reuse of recycled glass. Additionally, there is potential to replace traditional hot asphalt which has a much higher environmental footprint as it requires heating and the use of natural gas.

This product has provided the City of Whittlesea with more opportunities to use more recycled content in its road infrastructure projects and to close the loop on locally sourced recovered waste glass from kerbside recycling.

“Council is committed to finding infrastructure solutions that withstand changing climates and have minimal cost to our environment in its production and application,” said Lydia Wilson, Chair Administrator at City of Whittlesea, “It is very exciting to be partnering with industry leaders who are using new technologies and processes, so we can minimise our resource consumption and waste production.”

The pavement rehabilitation project was supported by Sustainability Victoria’s Sustainable Infrastructure Fund.

Procurement information

The City of Whittlesea partnered with suppliers, Repurpose It, in their application for funding through Sustainability Victoria’s Sustainable Infrastructure Fund. The requirement for recycled products was specified in the Request for Quotation. This was then compared to market rates of comparable products. The foam bitumen asphalt product containing recycled glass is unique to the manufacturer and was used to rehabilitate the pavement instead of using conventional asphalt.

The price of the foam bitumen asphalt product was compared to rates for the supply and placement of asphalt submitted by the City of Whittlesea’s established panel of approved civil and asphalt contractors and was found to be in line with market rates.

Installation and product performance

Installation was a positive experience by the City of Whittlesea, Repurpose It and the contractor, Metro. Repurpose It ensured the product was produced in accordance with its internal specifications and quality assurance procedure for placement by Metro. Metro was able to place the product the same way as conventional asphalt, so construction was considered straightforward.

Life-cycle monitoring and maintenance

Early visual monitoring indicates the pavement is performing well. The first round of pavement deflection testing was undertaken in September 2021 to compare pavement performance with adjoining conventional pavement, and the results are still being evaluated. Other early observations and test results indicate the pavement is performing to specifications.

This provided the City of Whittlesea with incentive and increased confidence to explore the use of foam bitumen asphalt and other road making products containing recycled materials, in future council projects. More testing will be undertaken in June 2022 to track the performance of the pavement over time.

More information

For more information about this project, please contact sustainableprocurement@sustainability.com.au

Gallery

More information

For more about this project, email sustainableprocurement@sustainability.com.au