TUNNEL VISION is the next generation of Subsurface Tunnel Infrastructure Inspection Radar that will scan and produce 3D virtual reality images of tunnel subsurface infrastructure defects, failures and technical issues in order to plan preventative maintenance. It simply addresses the global challenge of how to maintain a tunnel through non-destructive examination.

TUNNEL VISION is a vehicle-mounted system, which can see below the surface to inspect road and rail tunnels, tunnel utilities and tunnel linings.

TUNNEL VISION aimed at improving tunnel infrastructure resilience by reducing the risk of failure and contributing to reducing the whole life tunnel infrastructure costs. The project provided a new smart technology to inspect and maintain resilient integrated infrastructure and an example inspection is featured below.

Raster scans spanning the full 1220m of a rail Tunnel were obtained over two successive passes of TUNNEL VISION, with the antenna orientated and locked vertically upwards.

To ensure maximal penetrative depth was achieved, the frequency sweeping range of the GPR scans was set to the network analyser’s maximum 2.5GHz bandwidth. For pass one, the antenna was positioned along the centreline above the down-line. On pass two, the antenna position was adjusted to rest along the centreline above the up-line.

Vehicle speed was maintained at 2.8 during both passes to ensure uniform lateral incrementation between successive measurement events during each pass. Resulting raster visuals are presented in the Figure below.