Road network flaw to self-drive revolution

The Government’s self-driving motoring revolution requires more robust pavement designs which provide more long-term performance, advises Britpave the infrastructure industry association.

Under plans announced by the Department of Transport self-driving vehicles could be on UK roads by 2025. It said that self-driving vehicles could "revolutionise public transport and passenger travel, enhance transportation connections between rural communities, and reduce the number of road collisions caused by human error.” The proposals would see cars, coaches and lorries boasting self-driving features operating on UK motorways within the next year, followed by fully self-driving vehicles by the middle of the decade.

Benefits of self-driving vehicles include less accidents, improved use of road space, reduced congestion and pollution and more efficient fuel consumption. The vehicles would be equipped to ‘read the road’ and replicate the instinctive human ability to simultaneously observe, analyse, decide and react to every potential different road scenario such as potholes and reduced skid resistance.

Self-driving vehicles require well-maintained road surfaces. Surface friction levels, road markings and signs must be in good condition in order to be correctly read by the vehicles’ sensors. Embedded wi-fi antenna for vehicle connectivity needs to be protected from damaged caused by rutting from heavy traffic loads or the road surface melting in extreme temperatures.

Joe Quirke, Britpave chairman, explained: “The technological advancement of self-driving vehicles needs to be matched by investment in long-term, robust road solutions.”

In particular, Quirke pointed to the fact that, unlike human drivers who may slightly shift left or right within lanes, self-driving vehicles guided by GPS and other navigational aids will follow and keep to a far more precise path. This means that each self-driving vehicle will drive over the same part of the road each time leading to significant repetitive wear-and-tear and increased ongoing maintenance. He said: “To counteract this, roads will have to provide far more long-term robustness than they do at present. They will also have to have far more built-in climate resilience if they are to continue to operate during the extreme weather events predicted as a result of climate change.”

Concrete roads, that are already currently designed for a performance life of 60 years, offer the required levels of long-term strength and resilience.

He observed: “Concrete roads offer the robustness and resilience to withstand repetitive traffic loads as well as the structural integrity to support and protect installed sensors and wi fi antenna. A self-driving vehicle will only be as good as the road surface that it drives on.”