The geotextile fabric roll should be protected from damage before geotextile installation and unfolding. Geotextile rolls should be stacked in a flat place without water accumulation, the height of the stack should not exceed four rolls, and the identification film of the roll can be seen. Geosynthetics rolls must be covered with opaque materials to prevent UV aging. During the storage process, the integrity of the label and the integrity of the data should be maintained. During transportation (including on-site transportation from the material storage site to the worksite), the geotextile roll must be protected from damage.

Geotextile fabric rolls that have been physically damaged must be repaired. Geotextiles that are severely worn cannot be used. Any geotextile in contact with leaking chemical reagents is not allowed to be used in this project.

Geomembrane
Geogrid005

1  Geotextile installation method(How to lay geotextile fabric ?) :

  1. Use manual rolling, the cloth surface should be flat, and the deformation allowance should be properly left.
  2. The installation of filament or short-filament geotextile usually uses lap, stitch, and welding methods. The width of stitching and welding is generally more than 0.1m, and the width of overlap is generally more than 0.2m. Geotextiles that may be exposed for a long time should be welded or stitched together.
  3. Stitching of geotextile:

All stitching must be performed continuously (for example, spot stitching is not allowed). Before overlapping, the geotextile must overlap less than 150mm. The smaller stitch distance is at least 25mm from the selvage (the exposed edge of the material).

The sewn geotextile seams also include a line of chain stitching with a chain lock. The thread used for stitching should be a resin material with a smaller tension exceeding 60N, and has the chemical resistance and ultraviolet resistance equal to or exceeding that of the geotextile.

Any “drop stitches” on the sewn geotextile must be re-sewn in the affected area.

Corresponding measures must be taken to prevent soil, particulate matter, or foreign matter from entering the geotextile layer after installation.

The cloth lap joint can be divided into natural lap joint, seam joint, or welding according to the function of terrain use.

  1. During construction, the geotextile on the geomembrane is naturally lapped, and the geotextile on the geomembrane is sewn or welded by hot air. Hot air welding is a method of connecting filament geotextiles, that is, using a hot air gun to heat two pieces of cloth at a high temperature instantaneously to make part of it reach a molten state, and immediately use a certain external force to bond it firmly together. When hot bonding is not possible in wet (rainy and snowy days) weather, geotextiles should adopt another method—the stitching connection method, which is to use a special sewing machine for double-thread suture connection and use chemical UV-resistant sutures.

The smaller width is 10cm when stitching, the smaller width is 20cm when natural overlap and the smaller width is 20cm when hot-air welding.

  1. For the seaming, use the suture thread with the same quality as the geotextile, and the suture thread should be made of material with stronger resistance to chemical damage and ultraviolet light.
  2. After the geotextile is laid, the geomembrane shall be laid after approval by the site supervision engineer.
  3. The geotextile on the geomembrane is laid after the geomembrane is approved by Party A and the supervisor.
  4. The geotextiles of each layer are numbered TN and BN.
  5. The two layers of geotextile on the top and bottom of the membrane should be buried in the anchor groove together with the geomembrane where there are anchoring grooves.
geotextile fabric
Geosynthetics

1) The laying of geotextile basic requirements:

  1. The joint must intersect the slope line; where it is balanced with the slope foot or where stress may exist, the distance between the horizontal joint must be greater than 1.5m.
  2. On the slope, anchor one end of the geotextile, and then put the coiled material down on the slope and keep the geotextile in a tight state.
  3. All geotextiles must be held down with sandbags. The sandbags will be used during laying and will be reserved for the layer of material on top of laying.

2) Geotextile laying process requirements:

  1. Basic level inspection: Check whether the basic level is flat and solid. If there are foreign objects, handle them properly.
  2. Trial laying: Determine the size of geotextile according to the site conditions, and try laying after cutting. The cutting size should be accurate.
  3. Check whether the width of the Sarah is appropriate, the overlap should be flat and the tension should be moderate.
  4. Positioning: Use a hot air gun to bond the overlapping parts of the two geotextiles, and the spacing of the bonding points should be appropriate.
  5. When sewing the overlapping parts, the sutures should be straight and the stitches should be even.
  6. After stitching, check whether the geotextile is laid flat and whether there are defects.
  7. If there is any unqualified phenomenon, repair it in time.

3) Self-inspection and repair:

  1. All geotextile pieces and seams must be checked. Defective geotextile pieces and stitches must be clearly marked on the geotextile and repaired.
  2. The worn geotextile must be repaired by laying and thermally connecting small pieces of geotextile. The small pieces of geotextile must be 200mm less than the edge of the defect in all directions. The thermal connection must be strictly controlled to tightly integrate the geotextile patch and the geotextile, and there is no damage to the geotextile.
  3. Before the end of the laying every day, visually inspect the surface of all the geotextiles laid that day to confirm that all damaged places have been marked and repaired immediately, and make sure that the laying surface is free of foreign substances that may cause damage, such as fine needles and small iron. Nails and so on.
  4. The following technical requirements should be met when repairing geotextile damage:
  5. The patch material used to fill holes or cracks should be the same as the geotextile.
  6. The patch should extend at least 30 cm beyond the damaged geotextile.
  7. At the bottom of the landfill, if the crack in the geotextile exceeds 10% of the coil width, cut off the damaged part, and then connect the two geotextiles; if the crack exceeds 10% of the coil width on the slope, you must Remove the roll of geotextile and replace it with a new roll.
  8. The construction machinery and tools used in the work shoes worn by the construction personnel should not damage the geotextile. The construction personnel must not do things that may damage the geotextile on the laid geotextile, such as smoking or poking the geotextile with a sharp tool.
  9. For the safety of geotextile fabric materials, the packaging film should be opened before laying the geotextile, that is, one roll is laid and one roll is opened. And inspect the appearance quality.
  10. It is especially proposed that the geotextile shall be inspected and approved as necessary after arriving on the site.

Strictly implement the company’s “Geotextile Construction Acceptance Regulations”

4) Precautions for installation and construction of geotextile:

  1. Geotextile can only be cut with a geotextile knife (hook knife). If cutting in the field, special protective measures must be taken for other materials to prevent unnecessary damage to the geotextile due to cutting;
  2. While laying the geotextile, all necessary measures must be taken to prevent damage to the underlying material;
  3. When laying geotextiles, care must be taken not to let stones, a large amount of dust or moisture, etc., which may damage the geotextiles, block drains or filters, or may cause difficulties for subsequent connections, enter the geotextiles Or under the geotextile;
  4. After installation, visually inspect the surface of all geotextiles to identify all damaged landlords, mark and repair them, and make sure that the paving surface is free of foreign matter that can cause damage, such as broken needles and other foreign objects;
  5. The connection of geotextile must follow the following regulations: Under normal circumstances, there can be no horizontal connection on the slope surface (the connection must be along the contour of the slope surface and not intersect with it), except for the repaired place.
  6. If stitching is used, the stitching thread must be made of the same material as or exceeding the material of the geotextile, and the stitching thread must be made of chemical-resistant UV material. There should be an obvious color difference between the suture thread and the geotextile to facilitate inspection.
  7. When installing, pay special attention to the stitching so that there is no gravel in the soil or gravel covering layer into the middle of the geotextile.

5) Damage and repair of geotextile:

  1. At the suture joint, the re-suturing repair must be performed, and the end of the skipped stitch part has been re-sutured.
  1. In all areas, except for rocky slopes, loopholes or torn parts must be patched and stitched with geotextile patches of the same material.
  1. At the bottom of the landfill, if the length of the crack exceeds 10% of the coil width, the damaged part must be cut off, and then the two parts of the geotextile are connected.