Delivering Innovation

Using FM Conway’s single-layer solution, SureLayer® E, the Surfacing team laid 760 tonnes of material on Third Avenue in the Queens Park district of Westminster, containing a recycled content of 85% from a combination of high Polished Stone Value (PSV) Reclaimed Asphalt Pavement (RAP) and ‘recovered aggregate’.

By using warm mix, the project was able to deliver a more sustainable road surface. As warm mix is mixed and laid at a reduced temperature, this cuts energy usage and reduces the associated carbon when compared to traditional hot mix asphalt.

Thanks to the use of this new product as the solution to Westminster’s roads, the new warm mix also meant that the team could deliver a number of innovations on the project.

The use of warm mix asphalt provided the road surface with greater durability, due to the reduced damage caused to the bitumen in the manufacturing process, as well as using an odour suppressant for the first time.

This was implemented into the manufacturing and installation of the material, which helped to deliver a reduction in odours for both the operational staff and the wider public.

Challenges and Solutions

As WCC declared a climate emergency in 2019, with the aim of becoming carbon neutral by 2030, the task of finding low carbon alternatives was a top priority that needed to be considered on this project.

In order to ensure that the material was suitable for Westminster’s roads, FM Conway and WCC worked together to develop a palette of seven different options for the borough’s Planned Preventative Maintenance (PPM) programme.

By using the high recycled content and warm mix of SureLayer E, FM Conway were able to present a solution that helped to support WCC’s ambitions, with this mix providing sustainability benefits resulting from fewer plant and vehicle movements, as well as lowering the number of operatives needed to work around heavy plant, ultimately delivering a 40% carbon saving over traditional hot mix asphalt.

Due to the busy location working in the heart of London, disruption to residents and roads also needed to be considered.

However, by using warm mix asphalt, the single layer is far quicker to lay than hot rolled asphalt, increasing productivity and reducing the number of lorry movements by 55%.

This enabled the Third Avenue contract to be completed in four days rather than eight, cutting disruption to local residents in half.

Outcomes

The project was successfully delivered and has presented WCC with a solution to work towards their carbon neutral goals, with the site undergoing continual performance monitoring to ensure the durability and high quality of the materials used.

The use of high recycled content contributes towards a circular economy and has provided the industry with a more sustainable construction method for treating carriageways, which could deliver huge environmental benefits if adopted across the UK’s road network.