Geomembranes are factory-made sheets, mostly HDPE, LLDPE, PVC, flexible polypropylene or EPDM, joined on site by welding or bonding. Their job is containment, so every seam and penetration is tested, and holes are the main enemy. Polymer, thickness, texture and stress crack resistance are chosen to suit the chemistry, slopes, temperatures and loads of the job.
Geomembrane deployment starts Monday, so the subgrade has to be signed off and rolled smooth by Friday.
Most holes in a liner are made by people, not by design loads: no driving on exposed sheet, no knives left lying around and no studded boots.
Also heard as
- liner
- membrane
- FML
- flexible membrane liner
Related terms
HDPE
High-density polyethylene: the stiff, chemically resistant polymer used for most landfill and mining geomembranes.
LLDPE
Linear low-density polyethylene: a softer, more flexible geomembrane polymer that follows uneven ground better than HDPE.
PVC
Polyvinyl chloride: a flexible, plasticized geomembrane that folds and seams easily, used in ponds, canals and water features.
Textured geomembrane
Geomembrane with a roughened surface that raises friction against soil and other geosynthetics on slopes.
Liner
Everyday site name for a geomembrane, or for the whole barrier system it belongs to.