The geotextile roll shall be protected from damage before installation and deployment. The geotextile roll shall be stacked in a flat place without water accumulation. The height of the pile shall not exceed four rolls, and the identification piece of the roll can be seen. Geotextile rolls must be covered with opaque material to prevent UV aging. In the process of storage, keep the label and data complete. During the transportation process (including the transportation from the material storage place to the working place), the geotextile roll must be protected from damage.

The damaged geotextile roll must be repaired. Geotextiles which are severely worn shall not be used. Any geotextile in contact with leaked chemical reagent is not allowed to be used in the project.

Laying method of geotextile:　　

1. The cloth surface shall be flat with proper deformation allowance.

2. The installation of long wire or short wire geotextile usually uses several methods of lapping, sewing and welding. The width of stitching and welding is generally more than 0.1M, and the lap width is generally more than 0.2m. Geotextiles that may be exposed for a long time shall be welded or stitched.

3. Stitching of geotextile:

All stitching must be continuous (for example, spot stitching is not allowed). The geotextile must overlap by 150 mm less before overlapping. The distance between the small needle and the selvage (exposed edge of the material) shall be at least 25 mm.

The stitched geotextile joint includes 1 line of wire lock chain joint method. The suture shall be made of resin material with a small tension of more than 60N, and shall have chemical corrosion resistance and UV resistance equal to or greater than that of geotextile.

Any "missing needle" on the sewn geotextile must be sewn again at the affected place.

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

The lapping of geotextile can be divided into natural lapping, seam jointing or welding according to the terrain and use function.

4. During the construction, the geotextile on the geomembrane shall be overlapped naturally, and the geotextile on the upper geomembrane shall be welded by seam or hot air. Hot air welding is the connection method of the selected filament geotextile, that is, the hot air gun is used to heat the connection of two pieces of cloth at high temperature at the moment, so that some of them can reach the melting state, and immediately use a certain external force to make them firmly bonded together. When hot bonding cannot be carried out in wet (rainy and snowy) weather, the geotextile shall adopt another method, i.e. the special sewing machine shall be used for double suture connection, and the chemical ultraviolet resistant suture shall be used.

The small width is 10cm for stitching, 20cm for natural lapping and 20cm for hot air welding.

5. For stitching, the suture with the same quality as the geotextile shall be used, and the suture shall be made of materials with stronger resistance to chemical damage and ultraviolet radiation.

6. The geomembrane shall be laid after the geotextile is laid and approved by the site supervision engineer.

7. The geotextile on the geomembrane is laid after the geomembrane is approved by Party A and the supervisor.

8. The serial numbers of Geotextiles in each layer are TN and BN.

9. Two layers of geotextile on the upper and lower layers of the membrane shall be embedded in the anchorage groove together with the geomembrane.

Basic requirements for Geotextile laying:

1. The joint shall intersect the slope line; the distance between the horizontal joint and the slope toe shall be greater than 1.5m where there is balance or possible stress.

2. On the slope surface, one end of the geotextile shall be anchored, and then the coiled material shall be laid down on the slope surface to ensure that the geotextile is kept in a tight state.

3. All geotextiles shall be pressed with sandbags, which will be used during laying and retained until the upper layer of material is laid.

Geotextile laying process requirements:

1. Base inspection: check whether the base is flat and solid. If there is any foreign matter, it shall be handled properly.

2. Trial laying: determine the size of geotextile according to the site conditions, and trial lay it after cutting. The cutting size shall be accurate.

3. Check whether the width of the Salar is appropriate, and the lap joint shall be flat and moderately tight.

4. Positioning: use the hot air gun to bond the overlapping parts of the two geotextiles, and the distance between the bonding points shall be appropriate.

5. When stitching the overlapping parts, the suture shall be straight and even.

6. After stitching, check whether the geotextile is laid flat and whether there are defects.

7. If there is any unqualified phenomenon, it shall be repaired in time.

Self inspection and repair:

a. All geotextile sheets and joints must be checked. The defective geotextile pieces and seams must be clearly marked on the geotextile and repaired.

b. The worn geotextile must be repaired by laying and hot joining small pieces of geotextile, which are 200 mm less than the edge of the defect in all directions. The thermal connection must be strictly controlled to ensure that the geotextile patch and geotextile are closely combined, and there is no damage to the geotextile.

c. Before the end of each day's laying, the surface of all geotextiles laid on that day shall be visually inspected to make sure that all the damaged places have been marked and repaired immediately, and to make sure that the laying surface is free of foreign substances that may cause damage, such as fine needles, small iron nails, etc.

d. The following technical requirements shall be met when repairing the damage of geotextile:

e. The patching material used to fill holes or cracks shall be the same as the geotextile.

f. Patches shall extend at least 30 cm beyond the damaged geotextile.

g. At the bottom of the landfill, if the crack of geotextile exceeds 10% of the coil width, the damaged part shall be cut off, and then the two geotextiles shall be connected; if the crack exceeds 10% of the coil width on the slope, the coil geotextile shall be removed and replaced with a new coil.

h. The working shoes and construction machines and tools used by the construction personnel shall not damage the geotextile, and the construction personnel shall not do anything on the paved geotextile that may damage the geotextile, such as smoking or using sharp tools to poke

Precautions for Geotextile installation construction:

1. Geotextile can only be cut with geotextile knife (hook knife). If cutting in the site, special protection measures shall be taken for other materials to prevent unnecessary damage caused by cutting geotextile

2. At the same time of laying geotextile, all necessary measures must be taken to prevent damage to the next layer of material;

3. When laying the geotextile, care must be taken not to let the stone, a large amount of dust or water and other substances that may damage the geotextile, block the drainage channel or filter screen, or cause difficulties to the next connection enter the geotextile or geotextile;

4. After installation, visual inspection shall be carried out on all geotextile surfaces to determine all damaged owners, mark and repair them, and make sure that there are no foreign materials such as broken needles on the paved surface that can cause damage;

5. The following regulations must be followed for the connection of geotextile: under normal conditions, there shall be no horizontal connection on the slope (the connection shall not intersect with the slope along the contour of the slope), except for the place of repair.

6. If the suture is used, the suture shall be made of the same or more materials as the geotextile, and the suture shall be made of materials resistant to chemical ultraviolet. There shall be obvious color difference between suture and geotextile for inspection.

7. Special attention shall be paid to the stitching during the installation to ensure that no gravel in the soil or gravel overburden enters the middle of the geotextile. Same as wechat

Damage and repair of geotextile:

1. At the joint of suture, it is necessary to re suture and repair, and ensure that the end of the needle skipping part has been re stitched.

2. In all areas, except for rock slope sections, the holes or torn parts shall be repaired and stitched with geotextile patches of the same material.

3. 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 geotextile shall be connected.