12.03.18
NR trials drones for large railway structure inspections
Network Rail is trialling the use of drones to inspect large structures in a safer, more cost-efficient way.
The vehicles are being used on the London North Eastern and East Midlands route to examine five arch viaducts along the route, including the Grade 1 listed, 28-span Royal Border Bridge in Berwick-upon-Tweed, in Northumberland.
Since last year, the structures team has been working alongside AECOM consulting engineers, Network Rail’s air operations team, and Cyberhawk – a company that operates unmanned aerial vehicles (UAVs), commonly known as drones – to carry out the inspections, which give a panoramic bird’s-eye view of the structures.
Due to an increasing number of structural assessments, the team identified a need for a more efficient inspection method to supplement the more traditional access techniques typically used.
Terry Donaldson, scheme project manager at Network Rail, explained that other industries like oil and utilities already use drones to inspect their structures, such as pylons and rigs.
“As well as being cost-effective, this innovation has reduced the need for possessions, track access and roped access, reducing safety risk,” he said.
“The quality of the information our asset engineers have received has also been much better than what can normally be produced with standard inspection techniques.”
Prior to this new technique, engineers would take photographs as they carried out the inspection at height, abseiling down the structure, which could often be in dark and poor weather with limited views to where the person could reach or see.
Nick Tedstone, professional head of structures at Network Rail, added: “Increased use of UAVs can provide our engineers with higher levels of quality information to allow them to make the best possible decisions on the future of our structures assets.”
Not only do the images deliver a more comprehensive 360-degree view of the structures, showing defects clearly, they are also being stitched together with photogrammetry to create high-quality 2D elevations, 3D models, and cloud point surveys – which avoids the need for a separate dimensional survey.
Sam De’Ath, structures asset engineer at Network Rail, explained that the drones are an “excellent tool” for the inspection of arch viaducts, and further inspections with the UAVs are now being planned.
“Aerial inspections can’t fully replace an engineer with a hammer – some degree of tactile inspection is still needed – but we’re now able to use the better imagery to find areas of concern and target those,” he added.
Top image: bunsview
Have you got a story to tell? Would you like to become an RTM columnist? If so, click here.