High-performance drainage sheets are the primary material in siphon drainage systems. These sheets can be directly laid on completed waterproofing layers and concrete protective layers. The long edges of the sheets are heat-welded, while the short edges are joined in an overlapping manner. When encountering walls, the sheets must be flipped up to the required fraction. During backfilling, the soil should be filled from all sides. When the backfill exceeds 50 centimeters, vehicles can be used for gradual backfilling. Violent construction is strictly prohibited during the installation of high-performance drainage sheets.