Gabions

Gabions, as used in modern engineering practice, are compartmented, rectangular containers made of galvanized or PVC coated steel hexagonal wire mesh, and filled with stone.  The compartments, or cells, of equal capacity are formed by a factory-inserted wire netting dividers or diaphragms.  These diaphragms add strength to the container and help retain its rectangular shape during the filling operation.  Diaphragms also provide assurance that the fill will be equally divided and prevent shifting of fill.The gabions are then tied together to form a gabion structure.  These structures provide numerous advantages:

FlexibilityFlexibility is an important benefit of any gabion structure.  The double-twist hexagonal mesh construction permits it to tolerate differential settlement without fracture.

DurabilityGabions support plant growth which provides a living coating for the wire mesh and stones, adding to their durability.  Generally, the wire mesh is needed for the first few years of the structure’s life, because the voids between stones fill with soil, silt, and plant roots which act as a bonding agent for the stones.  Additionally, the double twisted hexagonal mesh won’t unravel if cut.

StrengthSteel wire hexagonal mesh has strength and flexibility to withstand forces generated by water and earth masses, and the pervious nature of the gabion allows it to absorb and dissipate much of that energy.  This is evident on coast protection installations where gabion structures remain effective long after a massive rigid structure fails.

Gabion mesh

PermeabilityGabion walls are pervious to water and stabilize slopes by the combined action of draining and retaining, precluding the development of hydrostatic pressure behind the gabion wall.  Drainage is accomplished by gravity, as well as evaporation as the porous structure permits air circulation through it.  As plant growth develops within the structure, the process of transpiration assists in removing moisture from the backfill  -  a much more efficient system than weep holes in standard masonry walls.

EconomyGabion systems are more economical than rigid or semi-rigid structures for the following reasons:  + Require little maintenance  + Installations does not require skilled labor  + Stone fill is available on site or from nearby quarries  + Requires little or no foundation preparation, as the surface needs     to be only reasonably level and smooth  + Gabions are porous, requiring no costly drainage provision.

LandscapingThe use of gabions in decorative landscaping is limited only by the creativity of the landscaper.  Gabions permit growth of vegetation and help maintain the natural environment of the area and have been effectively and economically used in parks, along highways, along stream banks and ponds, rock gardens, terraces, and patios.

Rockfall Netting is manufactured from galvanized or PVC coated Gabion wire.  Sold in rolls it is attached to extremely steep rock slopes.  If rocks are dislodged, the netting allows the rock to fall but stops it from rolling into the traffic right of way.