Landslide Barriers

General Application

The occurrence of shallow landslides can be expected to rise as global climate change causes increased storm and severe rainfall events and higher average temperatures in many regions. Combined with the ever increasing urban encroachment on valley sides, often underlain with unconsolidated fine-grained glacial and post glacial sediments or colluvium, the risk of these events impacting lives is a reality.

The use of flexible-net barriers to mitigate small, surficial landslides is a relatively new practice. They are used on open slopes to protect infrastructure from earth slides or flows of relatively small volumes (e.g. 100 m3), most often consisting of saturated fine materials.

The systems combine many characteristics from rockfall catchment fences and debris flow barriers. They have the general appearance of a traditional hinged rockfall catchment fence, but have much more robust posts and tighter posts spacing. This is because the landslide events tend to have low impact velocities but high static loading requirements.

Testing has been carried out on instrumented systems by repeatedly impacting the fence at the base of a flume with artificial mudflows.