International Tunnel Forum – Ecology, Digitalisation and Artificial Intelligence

Around 160 visitors attended the two successful International Tunnel Forum events organised by STUVA as part of InnoTrans 2026
Credit/Quelle: Klostermeier

The experts on stage not only delivered entertaining and insightful presentations on their specialist topics, but also answered questions from the interested audience. Drawing on numerous practical examples, the International Tunnel Forum once again offered fresh perspectives and provided a deeper insight into cutting-edge ideas and concepts relating to the planning, construction and operation of tunnels – and beyond.

Tunnels – Key to Ecology and Quality of Life

Dipl.-Vw. Bernd Kollberg (Intraplan Consult GmbH) discussed Standardised Assessment, which, in the field of transport infrastructure, is of central importance to local public transport as an official, methodical procedure for evaluating investments, since the federal and state governments use it as a basis for decision-making regarding the allocation of public investment funds. One sub-indicator in project evaluation is the emissions of greenhouse gases and air pollutants generated during construction and operation. If high greenhouse gas emissions result in the costs outweighing the benefits in the Standardised Assessment, this calls the construction project into question. Whilst there may be a clear need to construct a tunnel, for example, it is nevertheless advisable for planners to design the project in such a way that the volume of concrete and steel used is kept to a minimum. The building materials industry was encouraged to continue driving forward the reduction of specific greenhouse gas emissions from concrete and steel. Both factors have a positive impact on the assessment of planned construction projects.

InnoTrans took place in Berlin from 22 to 25 September, attracting more than 125 000 visitors from 128 countries. More than 600 exhibitors were represented in the Railway Infrastructure and Tunnel Construction exhibition segments
Credit/Quelle: Klostermeier

Univ.-Prof. Dr.-Ing. Michael Haist from the University of Stuttgart explored the topic of climate-efficient and resource-conserving concrete for tunnel construction in greater depth. “Sustainable tunnel construction is already possible today,” he stated.

 “Whilst we cannot achieve zero CO₂ emissions,” he added, “reductions of up to 50 per cent are certainly possible.” These reductions, however, are balanced against considerations of material quality and suitability for tunnel structures: the load-bearing capacity of various approaches to concrete compositions using new additives, and whether sustainability can be achieved “at the same price”, were further key aspects of the presentation.

Dr.-Ing. Peter Hoffmann (Schüßler-Plan Ingenieurgesellschaft mbH) gave a presentation on ‘Change Agents – Improving quality of life by strengthening sustainability skills’. Hoffmann is part of the project management team for the Hamburg U5 underground line – a project in which precisely these sustainability skills  in the planning of infrastructure projects are being put into practice. His presentation, using the example of the east-west axis in Cologne – which involves the construction of a 3.5 km-long underground line – once again addressed assessment criteria for tunnel construction projects that are increasingly coming to the fore: environmental sustainability and improving quality of life through new ideas for attractive living spaces as part of project planning. Noise reduction, minimising sealed surfaces (as illustrated by the Cologne project, for example, through the planting of 200 plane trees at Neumarkt as part of an underground route) – these and other planning aspects, aligned with the Global Sustainable Development Goals, are made quantifiable through the monetisation of the measures.

Although Klaus Rieker (Wayss & Freytag) was not on the podium, he spoke up from the audience to express his clear support: “There is a lot of talk about CO₂ and concrete, but it is precisely these environmental, social and health-related criteria that are not given sufficient consideration.” He advocated for these criteria to be integrated into the Standardised Assessment as well.

The closing presentation on the first day was given by Johanna Theilmann of DB InfraGO AG. She outlined ways to achieve sustainable railway tunnels and a climate-neutral rail infrastructure. She stated that rail is indispensable and must be expanded: “And we require tunnels. But tunnelling causes high emissions.” This, however, conflicts with Deutsche Bahn’s stated goal of achieving climate neutrality as a company by 2040. Alongside the potential for savings through planning and in terms of material properties and consumption, Theilmann identified the circular economy and recycling in construction projects, as well as construction logistics (with emissions that are significantly lower by comparison, but should not be overlooked) as levers for reducing CO₂ emissions in rail infrastructure. Maintenance also plays a role, provided that the aim of keeping maintenance as simple as possible, with minimal material consumption, is taken into account right from the project planning stage.

Digitalisation and Artificial Intelligence in Tunnel Construction and Operation

In the tunnelling sector, too, digitalisation has become an integral part of construction and planning, and artificial intelligence offers great opportunities for improvements, innovation and cost savings in both construction and operation. Dr.-Ing. Andreas Bach (Schüßler-Plan Digital) posed the question of whether there would be an AI revolution in tunnelling and civil engineering. To this end, he categorised the capabilities and applicability of various types of AI, explained the significance of available computing capacity and data volumes, and analysed the areas where there is a need for AI support and where AI is already superior to human performance. Given the rapid increase in the capabilities of AI, Bach believes the sector is set to undergo a fundamental transformation in its business and work processes. In addition to tailored solutions for the construction sector, he emphasised that, in particular, the right organisational culture is needed as a framework, along with users possessing the appropriate skills.

Dr.-Ing. Frank Abel discussed digital construction processes and the future role of AI in tunnelling in greater detail. He outlined current practices and future prospects, drawing on actual applications at Hochtief Infrastructure AG. Digitalisation in tunnelling has been evolving for 20 years now, from the processing and analysis of large volumes of data, through BIM models, to the current and future possibilities offered by AI. The challenges – a shortage of skilled workers, ageing infrastructure and geopolitical upheaval – are indeed significant, but digital technology also offers great opportunities. His conclusion: the successful and swift implementation of construction projects is of vital importance for our future. The sensible use of AI in construction projects can help to overcome these challenges.

Prof. Dr.-Ing. Gerhard Wehrmeyer of Herrenknecht AG focused specifically on automation and artificial intelligence to enhance performance, safety and efficiency in tunnel boring machines. Both technological solutions are applied in the fields of logistics, monitoring and system control, ring construction and TBM control. AI integration is taking place in almost all applications: from real-time monitoring of tunnelling data, through wear prediction, to the prospective control of the TBM from the surface; from the LLM-based co-pilot for the control stand and control centre to the analysis of excavated material – the possibilities in TBM technology are not only evident everywhere but have already been formulated in very concrete terms.