Geomembrane is a new kind of geomembrane, which is composed of plastic film and non-woven fabric. Its anti-seepage performance mainly depends on the anti-seepage performance of plastic film. At home and abroad, the plastic films used for seepage prevention mainly include polyvinyl chloride (PVC), polyethylene (PE), EVA (ethylene / vinyl acetate copolymer). In tunnel application, there are also those designed to use ECB (ethylene vinyl acetate modified asphalt blend geomembrane). They are polymer chemical flexible materials with small specific gravity, strong extensibility, high adaptability to deformation, corrosion resistance and low temperature resistance It has good frost resistance.