Sundolitt EPS improves £4.3m road junction in Newcastle

Sundolitt’s expanded polystyrene (EPS) has been used as an innovative void fill under one of Newcastle’s busiest roundabouts. The scope of the £4.3 million project was to remove and replace a notorious junction, by infilling the pedestrian subways and the main bowl of the roundabout. The junction, known locally as Cowgate roundabout, and renowned for being "dangerous and inefficient", now boasts new intelligent traffic signals to manage traffic flow and new cycle and bus lanes plus pedestrian crossings.

Sundolitt worked with Newcastle City Council to engineer and design the solution for the project. A total of 2000 EPS blocks - 2880 cubic metres - were used to infill the roundabout and the three pedestrian tunnels. The tunnels were filled first and finished grout and then the roundabout was completed to bring it up to road level. A layer of compacted stone was then placed over the polystyrene and the new road was then laid on top. The blocks can withstand loads up to 120kN/m², therefore with this high design load plus the compacted stone, the new junction can now safely carry thousands of motorists including up to seventy buses an hour.

The subways had been the source of repeated complaints by local residents to the Council, regarding anti-social behaviour and vandalism plus pedestrians were reluctant to use them, putting themselves at risk by attempting to cross the very busy road instead.

Adrian Walker, sales manager for Sundolitt commented, “Not only was EPS chosen as the solution for this project due to its robust nature, it also removed the need for heavy-lifting plant as it the blocks were easily cut and installed on site without specialist tools. This was an important factor as the project offered limited site access plus a requirement by the Council to keep the heavy traffic flowing during works.”

Councillor Ged Bell, cabinet member for investment and development from Newcastle City Council said: “The old Cowgate roundabout was an accident hotspot with ageing infrastructure and unpopular pedestrian subways so it was great to see it go.

“We invested over £4 million to turn it into a modern signalised junction with intelligent traffic lights, street-level crossings and cycle and bus lanes – making it safer and better for everyone.

“Using polystyrene blocks was a quick, effective and sustainable way to infill a huge area and bring it up to ground level. It also meant that we could keep all lanes moving during the infill as engineers could work in the bowl of the roundabout without impacting on traffic - which underpinned our commitment to keep disruption to a minimum as we made a major investment to one of the city’s busiest junctions.”

Sundolitt’s’ EPS offered a sustainable and cost effective solution for Newcastle City Council and has ensured a safer, greener and cleaner option for local residents as well improving journey times and reducing congestion.

As a void fill, EPS eradicates the environmental impacts of transporting thousands of tonnes of conventional ballast and eliminates the energy and environmental costs of quarrying whilst also ensuring an extremely lightweight infill solution with low moisture absorption and increased longevity.