thermobonding three layer drainage: It is a three-dimensional polypropylene mesh pad that forms a w-shaped longitudinal full-section drainage channel through special extrusion and two layers of needle-punched and heat-treated non-woven geotextiles to form anti-filtration, drainage, and protection through thermal bonding. thermobonding three layer drainage structure, where the unit area mass of the drainage core material is 420g / ㎡ (tolerance ± 10%), the unit area mass of the reverse filter layer is 105g / ㎡ (tolerance ± 15%), the longitudinal tensile strength is 14kn / m, 50kpa, hydraulic When the gradient i = 1, the plane water flow is 1.5x10-³㎡ / s, 100kpa. When the hydraulic gradient i = 1, the plane water flow is 1.3x10-³㎡ / s.
