ARTICLE

Meet the academic championing new road tech from smart sensors to sunflower oil

Nature-based green materials and condition monitoring sensors could become two novel ingredients of sustainable highways of the future — and researcher Dr Haopeng Wang is leading the promotion of new ideas.

Motorists, cyclists and pedestrians stand united in their frustration of poor road condition, and highway authorities are often playing catch up with repairs. But what if the carriageway could automatically alert councils when minor defects become apparent, or even heal itself before highway imperfections lead to the formation of potholes?

Clever innovations designed to achieve those aims and more are being developed by pavement engineers in the UK and are now being championed by asphalt specialist Dr Haopeng Wang. He is keen to explore options for using more digital technology in highways and advance the use of environmentally sustainable approaches to road construction and maintenance.

The research fellow from China works at the University of Nottingham’s transportation engineering centre, and is one of Connected Places Catapult’s four new Researchers in Residence appointed in May whose focus is to investigate circularity principles in construction.

Haopeng is currently scouring the country for some of the best new innovations in asphalt pavement design. He plans to publish recommendations for the roads sector, outline the most promising technologies available, and convene a group of professionals to take forward new opportunities.

“People may take roads for granted but they represent this country’s largest infrastructure asset, influence all of our daily lives and have a big impact on the economy,” he says. Highways rich with digital technology could, Haopeng adds, not only help to improve how roads are constructed and maintained, “but make them smarter and a lot more intelligent too”.

“Being involved in the Researchers in Residence scheme will bring me closer to industry, allow me to identify potential applications of new technology and explore further the concept of circularity principles in construction.

“Connected Places Catapult has offered contact with many industry stakeholders, allowing me to better understand their needs and expectations, which in turn will guide my research and make it more meaningful,”

Sensors and green materials

One recent idea is to embed Radio Frequency Identification chips in an asphalt pavement to monitor stresses and strains within a road surface and detect cracks. “The sensors send condition data to a central Cloud system that oversees the health of a road, allowing for authorities to make timely interventions,” Haopeng explains.

Another concept is the self-healing highway. Scientists have found that nature-based green materials, such as sunflower oil can reverse the ageing effects of bitumen – the material used to coat aggregate in an asphalt road – by making the binder less ‘viscous’, or sticky. Haopeng says that colleagues at Nottingham are developing capsules containing sunflower oil that can be buried within a road, releasing their contents only when asphalt begins to crack to help strengthen a highway and lengthen its life.

Further areas of interest for the research fellow include the use of rubberised crumb sourced from old vehicle tyres as a substitute for a proportion of virgin material used in road construction. “Every year we generate a vast quantity of waste tyres. By grinding them down into small granules, they can be introduced to the bitumen to replace some of the primary material,” he says.

Other applications involve the addition of crushed concrete, aggregate and glass to road materials. “Using recycled demolition waste from construction sites in highways also allows limited resources of natural aggregate to be preserved.”

In addition, the academic is exploring how roads could be designed to incorporate inductive charging technology, allowing electric vehicles to be recharged on the move rather than at fixed stations.

Committed to carriageway improvement

Haopeng Wang completed both Bachelor and Masters degrees in transportation engineering from Southeast University in China before moving to the Netherlands and receiving a Doctorate in pavement engineering from Delft University of Technology in 2021. He joined the University of Nottingham as a Marie Curie Fellow to focus on rubberised asphalt binders and was sponsored by the European Union’s ‘Horizon 2020’ programme.

“Civil engineering has been an interesting subject to pursue, and my career so far has involved many interactions with different people from several sectors such as materials science and chemistry,” he says.

Haopeng’s forthcoming research will involve literature reviews of new road technologies, before conducting interviews with project managers, contractors and materials suppliers to find out about their experiences, hopes or uncertainties of using sustainable materials. He will also visit sites in the London area to carry out inspections of recently laid recycled road materials and see works under construction.

Providing a service to society

He says that making highways more sustainable is a very important area of study. “The UK Government has a Net Zero strategy and infrastructure is a large consumer of materials and contributor to carbon emissions. By reducing the volume of materials used in roads we can help to reduce carbon.

“The work I am doing will hopefully be very useful to society,” he continues. “Road pavements are not always in the best condition, with potholes and unevenness on the roads made worse by extreme weather conditions such as high temperatures and flooding.

“Now with new technologies emerging, we can hopefully improve the performance of roads using recycled materials and make them as durable and resilient as traditional ‘hot mix’ asphalt.”

He adds that as the UK has progressed beyond its major road building programme, the focus going forward has to be on maintenance and making the best of the assets we currently have. “Very few universities in the UK specialise in road and pavement engineering, but it is an important area,” he remarks. “It is important that more research effort is put into this.”

Haopeng adds that academics working to further their research into specialist areas of study must “be really focused on their subject – and go as deep as they can”. But once that process is complete, it is just as important to “think of the bigger picture” of how one piece of research fits into a wider ecosystem. “You cannot solve all of the issues yourself.”

New grants of £50,000 are available to academics keen to become part of a growing cohort of specialists

*Haopeng Wang’s placement is funded by the Innovation Launchpad Network+, an EPSRC-funded project which focuses on bringing together leading universities and the Catapult Network. For more information, please visit the Innovation Launchpad Network+.