Geotextile rolls should be protected from damage before installation and unfold. Geotextile rolls should be piled in a level place without water accumulation, and the height of the pile should not exceed the height of four rolls, and can see the identification of the roll. Geotextile rolls must be covered with opaque material to prevent UV aging. During storage, keep labels intact and data intact. Geotextile rolls must be protected from damage during transport (including from the material storage site to the work site).
Physically damaged geotextile rolls must be repaired. Severely worn geotextiles cannot be used. Any geotextiles that contact with leaked chemical reagents are not allowed to be used in engineering.
How to lay the geotextile:
1. For manual rolling, the surface should be flat, and a proper deformation allowance should be reserved.
2. The installation of filament or short filament geotextiles usually use lap jointing, stitching and welding several methods. The width of stitching and welding generally more than 0.1m, and the width of lap joint is generally more than 0.2m. Geotextiles that may be exposed for a long time should be welded or sewn.
3. Stitching of geotextile:
All stitching must be continuous (eg, point stitching is not allowed). Geotextiles must overlap at least 150mm before overlapping. The minimum stitching distance is at least 25mm from the selvedge (the exposed edge of the material).
Sewn geotextile seams include at least 1 row of wired lock chain seams. The thread used for stitching should be a resin material with a minimum tension exceeding 60N, and have chemical resistance and ultraviolet resistance equivalent to or exceeding the geotextiles.
Any "missing stitches" in the sewn geotextile must be resewn in the affected area.
Appropriate measures must be taken to prevent soil, particulate matter or foreign matter from entering the geotextile layer after installation.
The lap of cloth can be divided into natural lap, seam or welding according to the terrain and function of use.
4. During the construction, the geotextile above the geomembrane adopts natural lap joint, and the geotextile on the upper layer of the geomembrane adopts seaming or hot air welding. Hot air welding is the preferred connection method for filament geotextiles, that is, use a hot air gun to instantly heat the connection of two pieces of cloth to a molten state, and immediately use a certain external force to firmly bond them together. . In the case of wet (rainy and snowy) weather where thermal bonding cannot be performed, another method for geotextiles - stitching method, is to use a special sewing machine for double-thread stitching, and use chemical UV-resistant sutures.
The minimum width is 10cm during sewing, 20cm during natural overlap, and 20cm during hot air welding.
5. For the stitching, should use the same quality suture thread with the geotextile, and the suture thread should be made of a material with stronger resistance to chemical damage and ultraviolet light irradiation.
6. After the geotextile is laid, the geomembrane shall be laid after get the approval of the on-site supervision engineer.
7. The geotextile on the geomembrane is laid as above after the geomembrane is approved by Party A and the supervisor.
8. The numbers of the geotextiles of each layer are TN and BN.
9. The two layers of geotextile above and below the membrane should be embedded in the anchoring groove together with the geomembrane at the part with the anchoring groove.
