Waterproof sheet, also known as geotextile membrane. Traditionally, a geotextile membrane with a thickness of ≥0.8mm is called a waterproof sheet, while a 0.8mm-thick one is simply called a geotextile membrane. It is a type of waterproofing material made from high molecular polymer as the basic raw material, and is categorized into homogeneous waterproof sheet and composite waterproof sheet.