Latest developments and current projects in mechanized tunneling, microtunneling, and pipe jacking
Dear Ladies and Gentlemen
Dear Colleagues
Whether it concerns urban densification, large-scale alpine projects, or underground energy infrastructure, mechanized tunneling has become an indispensable part of modern civil engineering. Since the first use of tunnel boring machines (TBMs) in 19th-century Europe—and in Switzerland since the 1960s—this excavation method has continuously evolved. Today, it is a key technology for the expansion of high-performance infrastructure networks worldwide. TBMs are now used for small diameters, such as the expansion of utility and supply lines in urban centres, as well as for large diameters in major infrastructure projects. This method also finds application in the construction of shafts and inclined shafts for hydroelectric power plants.
What are the latest developments in this excavation method? Where is innovation currently taking place? This year’s Swiss Tunnel Colloquium is dedicated to the topic: “Latest developments in mechanized tunneling, microtunneling, and pipe jacking.”
The first part covers large-diameter mechanized tunneling. In this section, manufacturers will provide insights into the latest developments directly from their workshops. Two contractors will report on their experiences and challenges when using state-of-the-art TBMs. To conclude the first part, a presentation will address a recent innovation in segmental lining: prestressed segment rings for use in the pressure shaft of the world’s largest pumped-storage power plant.
The second part focuses on smaller diameters—small, but no less significant. The rapid growth of urban centres worldwide would be unthinkable without pipe jacking and microtunneling. In this section, planners will present the fundamentals of design as well as practical experiences from various projects. This will be followed by a presentation on current projects under construction in Switzerland by a specialized contractor. Finally, we look “outside the box”: Swissloop Tunnelling will report on its technology. What are the differences compared to “classic” mechanized tunneling? Which areas of application are defined as target groups? When will the technology be market-ready? All these topics will be highlighted on June 16.
Once again, an exciting and diverse program awaits you this year. We look forward to welcoming you to the Colloquium 2026.
 | Eric Carrera
MSc ETH Bau-Ing. Lombardi SA, Bellinzona-Giubiasco |
 | Jade Senn Ing. civ. dipl. EPFL
STSym Committee / WSP Ingénieurs Conseils, Lausanne |
Swiss Tunnelling Society
