composite geomembrane-复合土工膜

Composite geomembrane is an impermeable material composed of geotextile and geomembrane, mainly used for anti-seepage. Composite geomembrane is divided into one cloth one membrane and two cloth one membrane, with a width of 4-6 meters and a weight of 200-1500g/m2. It has high physical and mechanical performance indicators such as tensile strength, tear resistance, and bursting resistance, and can meet the needs of civil engineering such as water conservancy, municipal engineering, construction, transportation, subway, tunnel, etc. Due to the use of polymer materials and the addition of anti-aging agents in the production process, it can be used in unconventional temperature environments.

performance

Composite geomembrane (composite anti-seepage membrane) is divided into one cloth one membrane and two cloth one membrane, with a width of 4-6 meters and a weight of 200-1500g/square meter. It has high physical and mechanical performance indicators such as tensile strength, tear resistance, and bursting resistance. The product has high strength, good elongation performance, large deformation modulus, acid and alkali resistance, corrosion resistance, aging resistance, and anti-seepage performance. It can meet the needs of civil engineering such as anti-seepage, isolation, reinforcement, and crack prevention reinforcement in water conservancy, municipal engineering, construction, transportation, subway, tunnel, and engineering construction. Commonly used for anti-seepage treatment of embankments and drainage ditches, as well as anti pollution treatment of waste disposal sites.

construction

Composite geomembrane is a composite geomembrane formed by heating one or both sides of the membrane in an oven using far-infrared radiation, and pressing the geotextile and geomembrane together through a guide roller. With the improvement of production technology, there is also a process of casting composite geomembranes. Its forms include one cloth one film, two cloth one film, two film one cloth, etc.

The geotextile serves as the protective layer of the geomembrane, preventing damage to the impermeable layer. In order to reduce the ultraviolet radiation and increase the anti-aging performance, it is better to use the embedding method for laying.

During construction, first use sand or clay with a smaller diameter to level the foundation surface, and then lay the geomembrane. Do not tension the geomembrane too tightly. The parts buried in the soil at both ends are corrugated, and then use fine sand or clay to lay a transition layer of about 10cm on the laid geomembrane. Build 20-30cm block stones (or precast concrete blocks) as a protective layer against erosion. During construction, efforts should be made to avoid stones directly hitting the geomembrane, and it is advisable to construct a protective layer while laying the membrane. The connection between the composite geotextile membrane and surrounding structures should be anchored with expansion bolts and steel plates, and the connection area should be coated with emulsified asphalt (2mm thick) for bonding to prevent leakage.

Water pressure measurement

Determination of Static Water Pressure Resistance of Composite Geomembranes

1. The principle of static water pressure resistance of composite geomembrane: After the pressure head on both sides of the composite geomembrane reaches a certain value, the composite geomembrane will rupture. Gradually increase the hydraulic pressure on both sides of the sample and maintain it for a certain period of time. When the seepage flow rate increases rapidly, it indicates that the sample has been damaged and the static water pressure resistance value of the sample has been obtained.

2. Maintain the above pressure of the composite geomembrane for at least 2 hours and observe the changes in the water level of the seepage pipe. If the water level of the composite geomembrane is basically stable (with a seepage flow rate of 0), increase the pressure step by step from 0.1 to 0.2 MPa, and maintain each level for 2 hours until a rapid increase in seepage flow rate occurs, indicating that the sample has ruptured. The previous level of pressure is used as the resistance to static water pressure (MPa).

3. If the composite geomembrane only needs to determine whether the geomembrane sample has reached a specified static water pressure resistance value, it can be directly pressurized to this pressure and maintained for 2 hours, and then judged to meet the requirements.

4. Each sample of composite geomembrane should be tested with at least 3 samples, and the low value should be used as the static water pressure resistance of the sample.