Gabion

Permathene gabion mesh is manufactured in a range of types including Al-Ten weld mesh, stainless steel weld mesh and woven gabion in both Galfan and polymer coated

AL-TEN Expected Lifespan

Although difficult to predict as lifespan of all steels is largely dependent upon the environment. Generally you can expect 20 years life for galvanized wire, and 2-5 times longer life span for AL-TEN™, PVC coated and stainless steel 316L.

The mesh life is dependent upon no damage to the coating during installation or during the lifetime of the wall. Because the wire is a coated mild steel any damage to the mesh which removes the Zinc/ Aluminium coating will eventually corrode. If upon inspection damage to the coating is seen or corrosion has occurred it needs to be rectified.

Other considerations when determining lifespan is soil PH levels if the product is placed directly on the earth. A geotextile fabric such as Syntex nonwoven 145gsm may be used as a separation layer. Some rock such as limestone has a high PH (alkaline) which may have a detrimental effect on the mesh.

Rock cleaning or other chemicals including acids and caustic solutions which come into contact with a Galfan, Galvanized, Stainless Steel mesh may have a detrimental effect to metal surfaces and may cause premature corrosion and breakdown at areas of contact. It is recommended to not use any chemicals and to wash immediately with water should contact occur. If exposure to corrosive type chemicals to Zinc and Aluminium is expected alternative systems should be considered following analysis of potential problems. Once corrosion has occurred it may be necessary to apply a rust remover and to then apply either a cold galv or zinc/aluminium paint to affected areas.

Aggressivity of Environment

Anticipated lifetime in years until 5% dark brown rust.

C1: Very Low (Internal buildings with clean atmospheres) 100 years +

C2: Low (Low level of pollution, mostly rural areas) 100 years +

C3: Medium (Urban and industrial atmospheres, moderate sulphur dioxide pollution, coastal areas with with low salinity) 93 years

C4: High (Industrial areas and coastal areas with moderate salinity) 47 years

C5: Very High (Industrial areas with high humidity and aggressive atmosphere, coastal and offshore areas with high salinity) 25 years

CX: Extreme (Extreme industrial areas, coastal and offshore areas with contact with salt spray) < 10 years