Lower carbon residential road improvement scheme delivered in Redbridge
We worked with Kenson Highways to deliver an innovative lower carbon residential road resurfacing scheme in the London Borough of Redbridge, saving more than 75 tonnes of carbon.
The project combined road resurfacing with flood mitigation measures on Heathcote Avenue in the Clayhall district and included the use of our evoZero carbon captured near-zero cement, as well as lower carbon asphalt containing reclaimed asphalt (RA), a biogenic binder and produced using our warm mix asphalt process, which were instrumental in cutting the carbon footprint of the scheme.
evoZero cement gains its low carbon credentials from the use of carbon capture and storage at Brevik, Norway, and chain of custody models and has a uniquely low Global Warming Potential. The product was used in the lower carbon concrete supplied by the company to form the kerb and edging haunching, as well as in the sub-base of the footway.
Lower carbon road resurfacing
We also supplied the asphalt to resurface the carriageway and footway on Heathcote Avenue. A total of 275 tonnes of binder course material was laid which incorporated 25 per cent RA as well as 6.5 per cent ACLA at the request of the client.
The 248 tonnes of asphalt surface course contained our CarbonLock bio-binder and was produced using Era 140 warm mix process. The CarbonLock binder contains biogenic materials that absorb and store CO₂ from the atmosphere during their life. This CO₂ is permanently ‘locked’ into the asphalt, even when it is recycled at the end of its life, reducing the carbon footprint of the asphalt.
It is estimated that the inclusion of biogenic materials within the binder locks in around six tonnes of CO₂ per kilometre of road, rather than releasing it back into the atmosphere. This helps further reduce emissions and provides at least a 25 per cent reduction in carbon emissions compared with standard hot mix asphalt.
Warm mix asphalt cuts carbon emissions
In addition, our Era 140 warm mix asphalt (WMA) process allows the material to be produced at up to 40ºC lower temperature than conventional hot mix asphalt, saving fuel and helping to cut the CO₂ emissions associated with production by up to 15 per cent. The lower production temperature also improves working conditions and allows faster completion of work.
The footway surface course was also produced using the Era 140 process and included 25 per cent RA – the first time this level of recycled materials has been trialled in a footway mix in Redbridge.
Supply chain collaboration
“The use of evoZero carbon-captured near-zero cement was vital in helping to minimise the carbon impact of the improvement project,” said James Moorhouse, Regional Director, Concrete at Heidelberg Materials UK.
“We worked closely with Kenson Highways to ensure all the materials used
performed correctly while also delivering the desired carbon benefits. The project is a great example of supply chain collaboration to meet the client’s objectives.”
David Shelley, Director, Kenson Highways, said: “Our aim on this scheme was to achieve the best possible carbon reduction.
“Initial calculations indicate that we saved over 75 tonnes of carbon overall, with the greatest single saving coming from the use of evoZero cement, which accounted for more than 35 per cent of the total.
“Without the support and expertise of Heidelberg Materials’ technical teams, and the introduction of these innovative low-carbon products, we would not have been able to achieve anything close to this level of saving.”
