The degradation of the main load-bearing system in tunnels, because of low temperatures, temperature changes and ice formation, has been studied in this research project which was already started in the second half of the 1990s.
The overall aim of the research has been to create basics to reduce the operating and maintenance costs required to secure tunnels for traffic, prevent traffic disruptions, damage to vehicles and installations caused by ice and falling rock and shotcrete. To reduce maintenance, improved knowledge is required about the degradation processes that low temperatures and freezing cause in our tunnels and thus relevant design tools can be developed, materials, systems and construction methods can be developed and selected that enhance sustainability and lower life cycle costs. Studies regarding the effect of temperature changes on the properties of shotcrete have been carried out, as well as measurements and analyzes of temperature flows in several of the Swedish Transport Agency’s tunnels.
Results from the research are already considered within the framework of the Swedish Transport Administration’s various governing documents.
The research reported is co-financed by BeFo, Formas and the Swedish Transport Administration.
The reference group that assisted the project was made up of Tommy Ellison, Thomas Dalmalm, Johan Funehag and Per Tengborg. Their in-kind efforts have contributed to the project’s success, but it is the work of Anna Andrén, with the supervision of Lars-Olof Dahlström and Erling Nordlund, and the financiers’ enabling of this long-term effort that has created an almost world-unique empiricism and data.
Stockholm
Patrik Vidstrand