1. Preparation before construction

Before laying the composite geomembrane, it is necessary to carry out relevant work such as acceptance of the previous process and preparation of the composite geomembrane.

(1) To lay a protective layer, a 10cm sand cushion layer or water stable layer can be laid at the bottom to prevent damage to the composite geomembrane. Based on the actual situation, the project adopts laying a 10cm water stable layer, requiring strength to meet the requirements and a smooth surface. The composite geomembrane can only be laid after passing the acceptance inspection by the supervisor.

(2) Before the composite geomembrane enters the site, it must be tested to ensure that its ductility meets the engineering requirements; And do a good job in storage and transportation to prevent damage to the composite geomembrane caused by sun exposure and transportation.

(3) Determine the laying, splicing, testing and acceptance methods to facilitate smooth construction.

2. Construction of composite geomembrane

(1) Laying of composite geomembrane

For the convenience of construction and to ensure the quality of splicing, wide width is generally used as much as possible to reduce the amount of on-site splicing. If there is a gradient at the bottom of the channel and some parts have irregular shapes, according to the actual engineering situation, the slope size is 6 * 15 meters, and the channel bottom size is 4 * 13. Cut at a dedicated site, transport to the work surface using suitable transportation equipment, and lay manually. In the laying project, manual cooperation is required to slowly roll from the top of the slope to the bottom, with a slow rolling speed, a flat surface, and appropriate allowance for deformation; During the laying process, equipment and personnel are prohibited from walking on the geotextile.

(2) Composite geomembrane splicing

There are several methods for splicing composite geomembranes, including overlapping, welding, sewing, and bonding. According to the technical requirements, I will use a combination of welding and bonding methods for construction. Generally, welding is used. When encountering arc transition sections or irregular shapes, geotextile KS special solid adhesive is used for bonding. When splicing, pay attention to the following points:

A. Professional equipment and skilled operators must be used;

B. Before welding or bonding, wipe the joint with clean gauze or cotton cloth to ensure that there is no water, dust, or dirt. Parallel alignment of composite geomembranes, with a minimum overlap of 10cm.

(3) Acceptance of composite geomembrane

After the composite geomembrane splicing is completed, the quality inspection personnel of our unit first conduct self inspection, rectify those that do not meet the requirements, and then report to the supervisor for acceptance. Only after passing the acceptance can we proceed to the next construction process. The inspection methods include vacuum method and inflation method. Mainly introduce the inflation method: the equipment includes an inflator, an air needle, and a vacuum gauge; There are two welded seams with a cavity of about 10mm between them. Seal both ends of the test section, insert an air needle, inflate to 0.05 to 0.2 Mpa, observe for 30 seconds, and check the vacuum gauge. If the air pressure does not decrease, it indicates that there is no leakage and the joint is qualified. Otherwise, it should be repaired in a timely manner. When repairing, the patch should be at least 10cm larger than the leak, and it must pass the acceptance inspection after completion.

3. Precautions

(1) Strengthen the protection of composite geomembranes and avoid exposure to direct sunlight. If the next process cannot be carried out due to special reasons, it should be covered and protected.

(2) It is necessary to lay and press at the same time to prevent the wind from blowing and causing tearing, wrinkling, etc. of the composite geomembrane. When pressing, sandbags should be chosen to avoid using hard objects such as stones to prevent wear and tear.

(3) During the laying process, check the appearance for any damages, dents, holes, or other defects at any time.

(4) When laying composite geomembranes, good weather conditions should be selected, and it is strictly prohibited to lay them in rainy or snowy weather. Measures should be taken to protect the already laid ones.

(5) Ensure a smooth appearance and meet the required quality standards