Geomembranes are widely used as moisture barriers (sealant systems). The membranes are manufactured from PVC, EPDM, EVA, FPO, HDPE, LDPE, LLDPE, VLDPE. For building use, the most suitable are membranes from PVC, EPDM & FPO, while the more widespread use of membranes for water storing in agriculture and sealing waste landfills are the membranes of polyethylene (PE).
Geomembranes are manufactured in widths of up to 13m. and thickness of 0.3 mm. to 2.5 mm.
Protecting geomembranes is of great importance because the mechanical stresses that can be induced during the construction or operation of a project can lead to failure (e.g. perforation or tearing) of the geomembrane. If it becomes apparent after it has progressed or completed the construction of the project (e.g. from leaks), the cost of repair is high.
Damage may result from random events, such as falling tools on the exposed geomembrane, vehicular traffic on it, as well as during the application of loads or during the operation of the project, especially when the geomembrane is at the base of embankments of significant height.
To protect the geomembrane against mechanical stresses, a geotextile is very often used in contact with the side expected to suffer from a puncture or a deformation action. The geotextile which should be used to protect geomembranes, is a nonwoven fabric.
The polyethylene (PE) geomembranes, contain 2.5% -3% carbon black for UV protection, to ensure maximum life, as well as a combination of antioxidants additives for optimal protection from heat during the manufacturing, the welding and its operation.
All the components and additives used in the manufacture of geomembranes (unless stated otherwise in their specifications) are approved for use in contact with potable water applications.
HDPE geomembranes have the highest tensile strength, impact, tear and puncture resistance and they exhibit very good resistance to environmental stress (ESCR), offering the highest chemical resistance.