Description
The geotextile roll shall be protected from damage before installation and deployment. The geotextile roll shall be stacked in a flat place without ponding, the stacking height shall not exceed the height of four rolls, and the identification piece of the roll can be seen. Opaque geotextile must be used to cover the anti-aging material. During storage, the integrity of labels and data shall be maintained. During the transportation (including the transportation from the material storage place to the working place on site), the geotextile roll must be protected from damage.
Geotextile rolls that are physically damaged must be repaired. Geotextiles subject to severe wear shall not be used. Any geotextile exposed to the leaked chemical reagent is not allowed to be used in the project.
Laying method of geotextile:
1、 The cloth shall be rolled and paved manually, and the cloth surface shall be flat with appropriate deformation allowance.
2、 The installation of filament or short filament geotextile usually adopts several methods of lapping, stitching and welding. The width of stitching and welding is generally more than 0.1M, and the overlapping width is generally more than 0.2m. Geotextiles that may be exposed for a long time shall be welded or stitched.
3、 Sewing of geotextile:
All stitches must be performed continuously (for example, point stitching is not allowed). The geotextile must overlap less than 150mm before overlapping. Smaller stitches shall be at least 25mm away from the selvage (the exposed edge of the material).
The sewn geotextile joint also includes a line of wired locking chain joint method. The suture used for stitching shall be a resin material with a smaller tension of more than 60N, and has chemical corrosion resistance and ultraviolet resistance equivalent to or exceeding that of geotextile.
Any "missing needle" on the sewn geotextile must be re sewn at the affected place.
Corresponding measures must be taken to prevent soil, particulate matter or foreign substances from entering the geotextile layer after installation.
The lap joint of cloth can be divided into natural lap joint, seam joint or welding according to the terrain and use function.
4 、
During construction, the geotextile on the geomembrane shall be overlapped naturally, and the geotextile on the upper layer of the geomembrane shall be welded by seam or hot air welding. 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 the two pieces of cloth at high temperature at the moment, so that some of them reach the melting state, and a certain external force is used immediately to make them firmly bonded together. In the case that hot bonding cannot be carried out in wet (rainy and snowy) weather, another method, suture connection method, shall be adopted for geotextile, that is, double-line suture connection shall be carried out with special sewing machine, and chemical ultraviolet resistant suture shall be adopted.
The smaller width is 10cm when stitching, 20cm when natural overlapping and 20cm when hot air welding.
5、 For sewing, suture with the same quality as 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 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 geotextile of each layer is numbered TN and BN.
9 、
The upper and lower layers of geotextile on the membrane shall be embedded in the anchor groove together with the geomembrane at the position with the anchor groove.
Basic requirements for Geotextile laying:
1. The joint must intersect with the slope line; Where the slope toe is balanced or there may be stress, the distance between the horizontal joints must be greater than 1.5m.
2. On the slope, anchor one end of the geotextile, and then lay down the coiled material on the slope to ensure that the geotextile remains tensioned.
3. All geotextiles must be pressed with sand bags, which will be used during laying and retained to the upper layer of material.
Geotextile laying process requirements:
1. Inspection of base course: check whether the base course is flat and solid. If there is any foreign matter, it shall be handled properly.
2. Trial paving: determine the size of geotextile according to the site conditions, and conduct trial paving after cutting, and the cutting size shall be accurate.
3. Check whether the overlap is flat and the width is appropriate.
4. Positioning: the overlapping parts of two geotextiles shall be bonded with a hot-air gun, and the spacing of bonding points shall be appropriate.
5. When stitching the overlapping part, the suture shall be straight and the stitches shall be uniform.
6. After stitching, check whether the geotextile is laid smoothly 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. Defective geotextile sheets and stitches must be clearly marked on the geotextile and repaired.
b. The worn geotextile must be repaired by laying and thermally connecting small pieces of geotextile, which are 200 mm shorter in all directions than the edge of the defect. The thermal connection must be strictly controlled to ensure that the geotextile patch is closely combined with the geotextile and has no damage to the geotextile.
c. Before the completion of laying every day, the surface of all geotextiles laid on that day shall be visually inspected to ensure that all damaged places have been marked and repaired immediately, and to ensure that there are no foreign substances that may cause damage on the laying surface, such as fine needles, small iron nails, etc.
d. The following technical requirements shall be met during the repair of geotextile damage:
e. The patch material used to fill holes or cracks shall be consistent with the geotextile.
f. The patch shall extend at least 30 cm beyond the damaged geotextile.
g. At the bottom of the landfill site, if the crack of the geotextile exceeds 10% of the width of the coiled material, the damaged part must be cut off, and then the two geotextiles shall be connected; If the crack on the slope exceeds 10% of the width of the roll, the roll of geotextile shall be removed and replaced with a new roll.
h. The working shoes worn by the construction personnel and the construction machines and tools used shall not damage the geotextile. The construction personnel shall not do anything on the laid geotextile that may damage the geotextile, such as smoking or stabbing the geotextile with sharp tools.
i. For the safety of geotextile materials, the packaging film should be opened before laying geotextile, that is, lay one roll and open one roll. And inspect the appearance quality.
j. In particular, it is proposed that the geotextile should be accepted, signed and measured in time after it arrives at the site.
Strictly implement the company's specification for construction and acceptance of geotextiles
Precautions for Geotextile installation and construction:
1. Geotextile can only be cut with geotextile knife (hook knife). If it is cut in the site, special protective measures must be taken for other materials to prevent unnecessary damage caused by cutting geotextile;
2. While laying geotextile, all necessary measures must be taken to prevent damage to the lower layer of material;
3. When laying the geotextile, care must be taken not to let the substances such as stones, a large amount of dust or moisture that may damage the geotextile, block the drainage channel or filter screen, or make it difficult for the next connection enter under the geotextile or geotextile;
4. After installation, the surface of all geotextiles shall be visually inspected to determine the location of all damage, marked and repaired to ensure that the laying surface is free of foreign substances that can cause damage, such as broken needles and other foreign matters;
5. The connection of geotextile must comply with the following regulations: under normal circumstances, there can be no horizontal connection on the slope (the connection must not intersect with it along the contour of the slope), except for the repaired place.
6. If suture is used, the suture must be made of the same or more than geotextile material, and the suture must be made of chemical ultraviolet resistant material. There shall be obvious color difference between suture and geotextile for inspection.
7. Pay special attention to stitching during installation to ensure that no gravel in soil or gravel overburden enters the middle of the geotextile.
Damage and repair of geotextile:
1. At the suture junction, 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 rock slope sections, the loopholes or torn parts must be repaired and stitched with geotextile patches of the same material.
3. At the bottom of the landfill site, if the length of the crack exceeds 10% of the width of the coiled material, the damaged part must be cut off, and then the two parts of geotextile shall be connected.
