Jackson Civil Engineering and its supply chain have developed a ground-breaking asphalt mix that can significantly reduce the carbon footprint of surfacing works.
The environmentally-friendly process was used to construct a new cycle path built for Birmingham City Council as part of the Bromford Flood Alleviation Scheme – a project Jackson and its supply chain partners are currently building in the Midlands for the Environment Agency.
Early calculations show the new low carbon foamed asphalt path, made from recycled aggregates and processed waste products, could bring CO2 savings of up to 90% compared with using a traditional hot AC20 asphalt mix.
Jackson’s supply chain manager Andy Lusher has been involved in the project from the start.
He said: “The cycle path provided an opportunity to look at the original design and ask ourselves how we could do this in a more carbon-friendly way. We brought our supply chain together to use their expertise and come up with a solution that was truly innovative.”
Partners on the trial scheme include O.C.O Technology Ltd, which has developed a carbon negative aggregate made from waste material from the treatment of flue gases from Energy from Waste (EfW) plants. This is the first time it has been used in a foamed asphalt application.
“With Zero Carbon being a global target, the construction industry must source alternative, more sustainable products to not only reduce the carbon footprint but to preserve the finite reserves of natural aggregate in the UK,” said Stephen Roscoe, O.C.O’s technical director.
Surfacing specialist Toppesfield has been central to the project. Its team took the O.C.O product and mixed it with ToppFoam, its own cold foamed bitumen asphalt that incorporates recycled aggregates that would normally go to landfill. On the back of the success of this trial, the company has opened a new aggregate recycling facility in Birmingham so that it can be closer to projects in the Midlands region.
Toppesfield’s technical director Paul Phillips said: “Working on the Bromford project has given us an opportunity to look at where we can reduce carbon in our operations further.
“Our strength and resilience tests show the new cold foam mix is fit for purpose, and as we strive towards Net Zero, we expect it to become the surface mix of choice for future path and light use road construction projects.”
Phase I of the 2.5km cycle path has been built, and work on the remainder is expected to start in April. It is projected that up to 70 tonnes of CO2 could be saved on its entire construction.
In addition, an impressive 30 tonnes of CO2 was saved using ultra-low carbon Cemfree concrete to bed and surround the kerbstones alongside the path. The product was developed by DB Group and produced by Accumix Concrete.
Group Commercial Manager for DB Group, Tony Sheridan, said: “This project is another example of the market-driven demand for real-world applications of sustainable construction products as the general public’s concerns over carbon emissions and climate change is felt.”
Duncan Haywood, Commercial Director for Accumix Concrete Ltd, added: “We have noted an increase in environmental awareness of our customers as they recognise the impact of ultra-low carbon concrete on their construction projects, and we’ve seen the value in making it easily available.”
Andy Lusher believes that this trial’s success means Jackson can be confident in specifying low-carbon concrete and asphalt in future projects.
He said: “We’ve learnt lots of lessons from this trial, and we know we can do something that pushes the boundaries but only with the full support and buy-in from our supply chain partners.”