Introduction
Dudley MBC aims to reduce the energy required and embedded carbon emissions in road resurfacing schemes through the application of innovative techniques and materials when it is appropriate to do so.
Retread - Insitu Recycling
Retread is a form of recycling as it involves breaking up and reshaping existing road materials before adding fresh bitumen. This means only 30mm of new surface course is required as a surface layer as opposed to the 100mm of digging and resurfacing required when more traditional techniques are used.
Dudley MBC has used insitu road surfacing since 2007 when a pilot scheme was carried out at Romany Way, Stourbridge. Following a period of monitoring retread was used in 2010 on three more roads (in Lower Gornal, Sedgley and Halesowen); in 2011 this method was used at another three sites (Roundhouse Road - Gornal, Dawlish Road and George Street - Woodsetton).
By reusing the existing road surface, fewer materials are disposed of in landfill sites and the lifespan of rock or mineral reserves is extended. This also reduces road transport which would otherwise import materials from elsewhere meaning less noise and disruption is experienced by local communities. The combination of these measures means the carbon emissions from each site are low. One contractor has produced case studies which indicate that savings in carbon emissions could be in the region of 40% by using the retread process.
This method is suitable for use on lightly trafficked estate roads.
Low Energy Asphalt
A Low Energy Asphalt has been used in 2011 by Dudley MBC to reduce the energy required to produce and lay road surfaces. This process allows the road surface to be produced at temperatures of 95°C, giving a reduction in fuel consumption of up to 50% compared with equivalent hot-mix materials (mixed at 160 to 180°C). Road surfacing projects can be completed faster and with less disruption. Dudley MBC has used this technique at two sites so far and is considering further locations for 2012.
The use of low energy asphalt at Swindon Road, Kingswinford saved 9.9 tonnes or the same carbon emission as 57,000 car miles compared to conventional road surfacing methods.
The constituent materials used are no different to conventional asphalt products, the only difference is in the method of mixing. The manufacturers therefore suggest that this method is suitable for use in all resurfacing applications.
For further information
Contact Mike Gower, Team Manager, Dudley MBC on 01384 814433 or email mike.gower@dudley.gov.uk
Return to the energy case studies search.
View the energy case studies map.
