Composite geomembranes are widely used in channel impermeability projects. The large number of applications of geosynthetic materials in civil engineering, especially in flood prevention and rescue projects, and their effectiveness have attracted the high attention of the majority of engineers and technicians. For the application technology of geosynthetic materials, the country has put forward the standardized technical requirements in terms of seepage control, back filtration, drainage, reinforcement and protection, which has greatly accelerated the pace of promotion and application of new materials. The material is widely used in the irrigation channel impermeability project, combined with construction practice, shallow talk about the application technology of composite geomembrane.

Brief introduction.

Composite geomembrane is an impermeable material made of geotextile fabric and geomembrane composite, it is mainly used for seepage control, composite geomembrane is divided into a cloth a film and two cloth a film, width 4-6m, weight 200-1500g/m2, tensile, tear resistance, top breaking and other physical and mechanical performance indicators, can meet the needs of water conservancy, municipal, construction, traffic, underground, tunnel and other civil engineering. It can be used in unconventional temperature environments due to its choice of polymer materials and the addition of anti-aging agents in the production process.

Performance.

The composite geomembrane (composite impermeable membrane) is divided into one cloth and one membrane and two cloth and one membrane, with a width of 4-6m and a weight of 200-1500g/m2, and high physical and mechanical properties such as tensile strength, tear resistance and top breakage. It can meet the needs of civil engineering such as seepage prevention, isolation, reinforcement and anti-cracking in water conservancy, municipal, construction, traffic, underground, tunnel and engineering construction. It is commonly used in the anti-seepage treatment of dykes and drainage ditches, as well as the anti-fouling treatment of waste sites.

Construction.

Composite geomembranes are formed on one or both sides of the film by far-infrared heating in an oven and pressing the geotextile and geomembrane together by guide rollers. With the improvement of the production process, there is also a flow-delay method to do the composite geomembrane process. Its forms are one cloth and one film, two cloth and one film, two films and one cloth, etc.

The geotextile acts as a protective layer for the geomembrane, so that the protective impermeable layer is not damaged. To reduce ultraviolet radiation and increase anti-ageing properties, it is best to use the buried method of laying.

During construction, the substrate must first be levelled with a small diameter sand or clay, and then the geomembrane must be laid. The geomembrane should not be too taut, and the ends should be buried in the soil in a corrugated form, and finally a transition layer of about 10cm should be laid on the geomembrane with fine sand or clay. A 20-30cm block (or concrete prefabricated block) is laid on top as a protective layer against erosion. During construction, every effort should be made to avoid stones hitting the geomembrane directly, and it is best to lay the membrane while the protective layer is being constructed. The connection between the composite geomembrane and the surrounding structure should be anchored with expansion bolts and steel plates, and the connection area should be coated with emulsified asphalt (2mm thick) to prevent leakage in this area.