10th Rock Mechanics and Tunnelling Day
On May 22, 2025, the 10th Rock Mechanics and Tunnelling Day took place at the WBI Center in Weinheim, Germany. This year, the very well-attended event focused on rock mechanics, tunnelling and underground construction, sustainability and project reports. It is organized annually by WBI GmbH, sponsored by the German Railway (DB InfraGO) and supported by the German Engineering Association (Arbeitskreis Bautechnik of the Württembergische Ingenieurverein).
Record Attendance
The large number of registrations for the 10th Rock Mechanics and Tunneling Day exceeded the capacity of the large lecture hall at the WBI Center in Weinheim this year. 320 visitors registered for the specialist event to attend the high-calibre, practice-oriented presentations by more than 20 experts from the fields of rock mechanics and tunnel construction. For the first time, the presentations were therefore also broadcast on monitors set up on two floors above the hall to give all guests the opportunity to follow the exciting program without restrictions.
Opening Presentation
The opening presentation, titled “General Renovation in Germany – Initial Experience from the Riedbahn,” was given by Gerd-Dietrich Bolte, Head of Infrastructure Projects Central, DB InfraGO AG. Why general renovation with total closure? Increasing traffic volume on the main railway lines and insufficient investment are leading to record delays. Conclusion: the railways are simply too full. “With the general renovation, we are getting the most out of the existing infrastructure in a compressed construction period,” said Bolte. And: Single-track operation would also lead to significant capacity losses. The Riedbahn, said Bolte, has provided insights into how things can be done differently: parallel work, stable replacement transport, and, as a result, “not just a replacement, but an improvement to the existing infrastructure.”
Rock Mechanics, Tunnelling and Underground Construction
The first segment began with a presentation by Dr. Patricia Wittke-Gattermann and Prof. Walter Wittke entitled “Seepage flow in rock and its impact on structural engineering measures – model and practical application.” In addition to explaining the basics of seepage flow, examples were used to show, among other things, how flow pressure can affect the stability of tunnels in the working face area. The calculations for developing groundwater models based on the principles of permeability of fractured rock were explained using two practical examples.
The following presentation on compressed air in mechanical and conventional tunnel driving in soil and rock was given by Dr. Martin Wittke and Dipl.-Geol. Albert Wimmer. The connecting tunnel to rescue shaft RS 3 of the 2nd Munich S-Bahn main line and the TBM excavation of the Filder Tunnel in the Stuttgart 21 project were chosen as practical examples of compressed air support for the tunnel face.
Other presentations dealt with the digitalization and automation of tunnel boring as well as innovations to accelerate the renovation of Deutsche Bahn railway tunnels. Deutsche Bahn’s portfolio comprises a total of around 750 tunnels with a total length of 600 km. Around 140 km of these are the oldest tunnels, which have been in operation for over 100 years and will need to be renovated in the coming years. Optimisations and innovations are being developed to reduce construction time and the associated significant disruption to rail traffic. Dipl.-Ing. Uwe Kneißl presented one possibility: single-shell shotcrete construction, which is to be used on a 150–200 m long pilot section in the Cramberg Tunnel.
Sustainability and Projects
The sustainability section focused on topics including alkali-activated binders. These cements are considered a promising option for reducing CO2 emissions in concrete production. A practical example of the use of CO2-reduced concrete was provided in a presentation by Dr. Frank Abel on the construction of phase 2 of the London Power Tunnel.
The lecture segment on construction projects included a report on the planning, implementation, and quality control of the lifting injections for the Marienhof station in the large-scale project of the 2nd Munich S-Bahn main line. Complex inner-city constraints and special geological conditions were the core topics of a presentation on hard rock tunneling in the West Link Korsvägen project in the center of Gothenburg. The event concluded with a report on experiences gained during the construction of the B10 Rosenstein Tunnel in Stuttgart, which is located in the core zone of a mineral spring protection area and therefore required special structural engineering solutions.
Save the Date
The date for the 11th Rock Mechanics and Tunnelling Day has already been set: it will take place on June 11, 2026 at the WBI Center in Weinheim.
Marvin Klostermeier
