Recycled glass in road base
Waste management is a major environmental concern across the world. Currently in Australia, approximately one million tonnes of waste is generated per annum. Of that one million tonnes of waste, approximately 50% is recycled.
This means that there is a huge opportunity for the construction industry to assist in improving waste management practices. The construction industry can assist through increasing reuse and recycling, to help reduce the mass of waste that ends up in landfill sites.
Since September 2020, the R2P Alliance has been driving a vigorous process to evaluate the use of recycled glass as a subbase layer of the pavement design on the R2P Project. The risks assessed range from health, safety and environmental aspects to structural integrity and compliance with specifications.
Following collaboration between the Department of Infrastructure and Transport, ResourceCo, City of Port Adelaide Enfield Council and the R2P Alliance, approval to implement a trial of recycled glass as a subbase layer of the pavement design was granted in December 2020.
In January 2021, the R2P Alliance became the first project in South Australia to trial the use of a 5% recycled glass as a subbase layer. The trial was implemented as part of the heavy vehicle bypass road “Exeter Terrace”, at the intersection of Oxenham Street.
A total of 170 tonnes of this product was trialled, which equates to 8.5 tonnes of recycled glass used in the subbase layer.
The aim for the trial is to prove that surplus glass can be recycled and used successfully as part of road construction in South Australia. This is a significant initiative, as it will help to pave the way forward for using more recycled materials in South Australian roads.
The trial was planned such that a side-by-side comparison to pavements with more traditional recycled subbase layers could be made. In line with the project documentation, the performance of the pavements will be monitored for three years after the R2P Project completion.