Tunnel Condition Monitoring

A way out of manual inspection

Modern transport infrastructure would be inconceivable without tunnels. In Germany, there are more than 400 road, rail and underground tunnels requiring regular maintenance. Many of these tunnels have been in operation for decades, so regular maintenance and repair are becoming increasingly important in order to avoid safety risks and consequential damage. Today, an inspection is performed manually in a slow, costly and unobjective process – the degree of digitization is low. In the near future, however, Building Information Modeling (BIM) will also become the standard in tunneling requiring complete digitalization of the building information. Fraunhofer IPM develops technical measurement solutions for a cost- and time-efficient inspection process during regular operation.

Tunnel Inspection System TIS

The optical multi-sensor system TIS will enable a fast and efficient inspection of tunnel structures in the near future. The system is currently being developed as part of the Fraunhofer IncaS and Eurostars OpOrTunIty research projects. A laboratory demonstrator is under testing. Market entry is planned by 2020.

TIS will provide absolutely referenced and high-resolution information on 3D geometry, surface structure and wall moisture of tunnels. A novel scanning technology and high-performance electronics allow high measuring speeds and thus for the first time a fast and continuous tunnel inspection. The multispectral sensor system is based on a multi-wavelength laser scanner and a novel light deflection unit, which for the first time enables full 360° scanning of the structure. A measuring and consequently driving speed of the inspection vehicle that is four times higher than that of available systems while maintaining the same data quality enables the simultaneous acquisition of relevant condition characteristics in a single measuring run. This makes blocking the structure for inspection unnecessary. The compact and flexible system design also allows use on a wide variety of mobile platforms such as pigs, trains or road vehicles.