Tunnel Technology


The Tunnel Technology Department is concerned with various aspects related to the safe and economical operation of road tunnels. Among other things, the Institute of Highway Engineering at RWTH Aachen University focuses its research on issues relating to the safety and ventilation systems of tunnel facilities and on the investigation of relevant fluid dynamic phenomena by means of simulation. In addition to the safety aspect, environmental issues also play a decisive role.

  Schematic diagram of a tunnel with vehicles Copyright: © ISAC

Tunnel Technology is in active exchange with the fields of civil engineering and traffic engineering. The questions posed in civil engineering concerning roadway materials and pavement structures are thus also relevant in tunnels. Video detection, an important component of traffic engineering, is also frequently used for traffic control in road tunnels.

Also with a view to the future practical application of what has been learned, ISAC attaches great importance to interdisciplinary and up-to-date teaching.


Photo of Nils Lichtenberg © Copyright: ISAC


Nils Lichtenberg

Head of Tunnel Management Department


+49 241 80-20383



Research Focus in Tunnel Technology


The ventilation of tunnels in case of fire is one of the central topics of tunnel technology, not least because of the potentially serious effects of a fire. In addition, the institute also deals with ventilation in regular operation. Improving tunnel ventilation holds great potential in many respects. In addition, reducing the frequency of the need to ventilate a tunnel conserves given resources in both economic and ecological terms. Lessons learned in improving ventilation systems can be implemented in new construction as well as integrated into existing tunnels.


Statistically spoken, driving through a tunnel is actually safer than driving on an open road, as the roofing provides constant car-friendly driving conditions. On the other hand, the effects of accidents in tunnels can easily be more devastating than on open roads. The current safety situation in German tunnels is quite satisfactory, but there is still room for improvement. Further research into options for fire suppression, fire detection and fire fighting can be mentioned here as an example. Here, too, there is the option of retrofitting existing tunnels.


Another research focus in Tunnel Technology at ISAC is the work with simulations. Simulations have the advantage that they allow real-scale imaging of flow phenomena. Experimental Model setups are limited to a smaller scale and the flow behavior is therefore altered, one only gets an approximation of the real conditions. In contrast to a model, a change of parameters in the simulation is comparatively easy to implement. Nevertheless models are used to validate and verify simulations. In the coming years a water model tunnel will be built and put into operation at ISAC, which will enable better visualization of the distribution of exhaust gases or the mixing of tunnel air and exhaust gases.