Measures against rockfall

Personal measures

Rockfall usually arises spontaneously. Hence the most effective personal preventive measure is to avoid areas at risk from rockfall (often indicated by a rockfall warning sign; known rockfall activity in the past). This includes not remaining under rock faces for unnecessarily long periods of time and moving past scree slopes quickly and carefully.

Construction site rockfall Gurtnellen
Rockfall nets at Harder
Technical/biological measures
  • Unstable sections of rock are blasted in a controlled manner
  • Pinning/anchoring of rock sections
  • The application of shotcrete prevents weathering of the rock. Dams and safety nets offer protection against rockfall and block fall to endangered objects such as roads and buildings.
  • Protective forests

 

Regional planning measures and local protection
  • Planning measures: avoidance of endangered areas, i.e. no designation of building zones in these areas.
  • Local protection: diversion dams, careful modifications to the terrain including deposition of rock and soil at the side adjacent to the slope, structural design of the wall adjacent to the slope (e.g. in reinforced concrete) to provide protection against the impact of falling objects, and minimum openings (windows and doors) in the wall.

 

Organisational measures
  • Emergency planning: Whilst rockfall is usually unpredictable, impending smaller and larger rock avalanches are often noticeable several days or weeks in advance by virtue of increased rock and block fall activity. Here, emergency measures (monitoring, early-warning systems, evacuation, sealing off of roads, etc.) can be taken.