Prevention of rockfalls is often extremely difficult owing to site access and the extent of the instability. Superficial instability of the rock face occurs as a result of thermal cracking, chemical changes in the rock, wind/rain erosion, hydrostatic pressure, plant roots and seismic actions.
 
Maccaferri has a long history in providing drapery systems to contain rock fall from affecting the safety of infrastructure networks. Maccaferri products include double twist wire mesh netting and Steelgrid.
  
The design of a drapery system must consider the realistic amount of debris that will dislodge from the rock face over a period of time. This rock will fall contained between the mesh and rock face to the base of the rock face. The termination point could be either a trench to accommodate the volume of rock or if space is limited then the rock can be contained within the mesh. 

Maccaferri has developed MAC.RO software to calculate these loads on the mesh and the required anchorage resistance at the crest resulting from the debris pocket at the bottom slope. What also has to be considered is the acceptance of the presence of a “pocket” with a certain size close to the road pavement or buildings. The width of the debris must also be compatible with the distance to the road pavement also to allow periodical maintenance.