Geomembrane is a geotechnical impervious material made of plastic film as impervious substrate and non-woven fabric. Its impermeability mainly depends on the impermeability of plastic film. At present, the plastic films used for seepage control at home and abroad mainly include polyvinyl chloride (PVC), polyethylene (PE) and EVA (ethylene/vinyl acetate * * * polymer), and ECB (ethylene-vinyl acetate modified asphalt * * * mixed geomembrane) is also used in tunnel application. They are a kind of polymer chemical flexible materials with low specific gravity, strong ductility, strong deformation adaptability, corrosion resistance and low temperature resistance. Geomembrane is a waterproof and impervious material based on polymer. Mainly divided into: low density polyethylene (LDPE) geomembrane, high density polyethylene (HDPE) geomembrane and EVA geomembrane. 1. The width and thickness are all finished. 2. It has excellent environmental stress cracking resistance and excellent chemical corrosion resistance. 3. Excellent chemical resistance. It has a wide temperature range and a long service life. 5. Used in landfill, tailings storage yard, canal seepage control, dam seepage control and subway engineering.