... closed to the protrudingcylinder shell to form a bump-like membrane, shell continuous, with a high degree of three- ... or concrete backfill. Main Technical Indicators of HDPE Green Roof Drainage SheetFeatures:1. Strong tensile strength, high elongation rate ... force, etc.Typical Application:1. Green Engineering: garage roof greening, roof garden, roof garden, soccer fields, golf courses, beach project.2. ...