CONTRACTORS have gone an extra green mile when resurfacing the Warwick Bypass.
They have recycled more than half of the materials from the old dual carriageway back into the new one – cutting the carbon footprint by nearly a quarter.
Some 17,432 tons of material were reused from the layers of road surface and saved from landfill as well as helping to make the A46 Warwick Bypass much smoother and safer for drivers.
A stretch of the busy road had deteriorated to a condition that, following a number of temporary repairs to ensure safety, a full depth reconstruction was needed, digging down almost 15 inches to replace the layers of road surface.
Kier led the project on behalf of National Highways and recruited Aggregate Industries (AI) to carry out the resurfacing on 3.5 miles of the northbound carriageway between Sherbourne roundabout and the Leek Wootton roundabout.
Much of the material in the lower levels contained tar which is classed as carcinogenic – has the potential to cause cancer – and must be dealt with as hazardous waste and disposed of at a licenced waste processing facility.
But tar-bound material can be safely recycled and encapsulated back into the pavement layers by processing and re-mixing it.
Kier and AI devised a low carbon pavement solution for the resurfacing project and discovered the greenest and most cost-effective way to do this was by recycling the existing carriageway material and reducing the amount that would have to go to landfill.
The old layers of road were recycled back into the new carriageway using AI’s ex situ cold recycled Foamix asphalt. Foamix is a fully cold process and can be laid and compacted at a much safer ambient temperature which reduces the asphalt fumes on site which workers are exposed to.
The material was mixed on site to minimise vehicle movements and reduce the scheme’s carbon footprint. Using recycled material meant there was less raw material needed for the works too and without the trips to the waste site as well, around 82,000 road miles were saved on this scheme.
Some 56 per cent of materials were recycled from the old road into the new one. Any remaining material not used in this scheme, which ran between late July and September, was recycled back across the road network through other projects.