Building and maintaining infrastructure at high elevations is a major challenge. Extreme weather conditions, complex geological conditions and natural hazards like avalanches and rockfall all have an impact on construction sites and buildings. Where there is permafrost, the ground often contains ice, which can grow, melt or creep. The upper layers of the permafrost melt in summer (active layer), and water accumulates on the underlying ice. These processes mean that the ground structure and its geotechnical properties may change during the service life of a built structure. This problem is exacerbated by climate change and the thermal impact of the infrastructure on the ground. Building methods must therefore be adjusted to take account of this.

Infrastructure on permafrost

Structures typically found in the Swiss Alps include mountain railway and cable car stations, pylons, restaurants, mountain shelters, water pipelines, avalanche barriers, telecommunication facilities, snow sheds and railway tracks. These play a crucial role in tourism, communication, energy supply, and protection against natural hazards. Special building and monitoring methods should be applied to guarantee the sustainability and safety of such infrastructure. We offer practice-oriented advice regarding construction and renovation projects on permafrost and have published a practical guide entitled ‘Building on permafrost’ (in german). Furthermore, our technical guideline ‘Defence structures in avalanche starting zones’ contains recommendations on building defensive structures on permafrost.