New Britpave guide to concrete road pavements

A new Britpave ‘Guide to Concrete Road Pavements’ explains how a wide range of concrete options can address the many challenges being faced by our road network.

The strategic and local roadworks are facing considerable challenges not least of which are the predicted increases in traffic demands. Traffic on the strategic road network is forecasted to increase by 60% from 2010 to 2040. Meanwhile, urban and local roads carry nearly 80% of all traffic. In addition, there is a greater expectation of roads in terms of whole life costing, long-term performance, minimum maintenance, journey reliability, low noise and high recyclability.

There are a number concrete road pavement solutions that are able to meet these challenges. However, although they are tried and tested overseas, they have yet to have widespread recognition and use in the UK. The new Britpave guide hopes to address this by providing details of a range of road pavements that can not only meet the demands being placed on today’s roads but could also provide solutions for the future. The options discussed include Continuously Reinforced Concrete Pavements (CRCP), Exposed Aggregate Concrete Surface (EACS) Roller Compacted Concrete (RCC), Groove and Grind and Whitetopping.

Whilst all of these have particular features, they share a number of performance benefits such as long-service life of up to 50 years, minimum maintenance, and 100% percent recyclability. In addition, they offer a key benefit to today’s heavily trafficked roads: noise reduction.

In the UK, the favoured option to reduce the level of road surface noise has been to apply a thin asphalt surface course. Unfortunately, thin asphalt layers soon need replacing and so no not offer long term performance. EACS has a specific noise reducing texture where the aggregate at the surface is left exposed. This results in random contact between tyre threads and the road surface which reduces traffic noise by up to 3 dBA. This is equivalent to halving the traffic flow. On those groove and grind treated sections of the A12 and A14 a noise reduction of 4 – 6 dBA and 54% improvement in skid resistance has been reported.

Long-term performance and noise reduction benefits are not the only issues. The new guide explains how not only can concrete roads be up to 30% cheaper than a fully flexible pavement option but they can also provide much better whole life cost benefits. For a typical 10km dual carriageway after 40 years a fully flexible pavement option, due to resurfacing and reconstruction needs, will be almost 2.5 times more expensive than the EACS option.

The guide also examines possible future applications of concrete road pavements. In the future it is predicted that roads will no longer just be a medium to go from one place to another. Instead of being inanimate they will have a number of active infrastructure roles.

These could include having integrated transmitter and connectors for easy vehicle battery recharging and internet connection for traffic and road condition updates. Sweden has already opened its first stretch of electrified road that allows lorries to recharge as they drive along it. At the University of Huston, Texas, researchers are working on incorporating carbon nanofibre heating elements in concrete roads to melt snow and ice whilst in the Netherlands the world’s first road that can harvest energy from inserted solar panels was opened in 2015 and promised significant potential. Keeping with the Netherlands, researchers have found that concrete pavements that incorporate titanium dioxide reduce nitrogen oxide, one of the main vehicle pollutants, by up to 40%.Meanwhile, in the UK researchers at the universities of Bath, Cardiff and Cambridge are working on a self-healing concrete that uses bacteria to seal cracks to further reduce maintenance and improve structural service life.

For a free download of ‘A Guide to Concrete Road Pavements’ visit the publications section of www.britpave.org.uk