Is the durability of composite geomembrane important?

When composite geomembrane is applied to hydraulic structures, durability is the most worrying issue in engineering circles, and it is also a very important issue. The natural aging test is the most direct and effective test method to evaluate the durability of composite geomembrane. Geomembrane has been used by dam workers at home and abroad for more than 40 years. The measured data shows that the ultimate tensile strength and elongation of the polyethylene film buried in the dam after 15 years have only decreased by 5%; long-term operation shows that the geomembrane has strong anti-aging ability; the former Soviet Union "On the application of earth-rock dam "Precautions for polyethylene impermeable structure" stipulates that buildings with a service life of less than 50 years can use polyethylene film.






In recent years, there have been many research results in the application of geosynthetics in China. Geosynthetics will age rapidly in the direction of high stress when under compression, and slowly age in the direction of low stress; if the stress level is limited to less than 20% of the maximum tensile force, the service life can reach 100a. The composite geomembrane anti-seepage body adopts polyethylene membrane and is located on the upstream dam slope. Both the upper and lower layers are equipped with earth and stone protective layers, which are less stressed and prevent ultraviolet radiation. Test data shows that its service life can be up to 50 years. At the same time, the field durability test and strain monitoring area of the composite geomembrane has been established. The dam and the left abutment are connected to the upstream side, and 5 test areas have been opened for 5 years, 10 years, 15 years, 20 years, and 30 years. The raw materials, construction technology and operating conditions are in line with reality. After the service life is reached, the wear resistance and anti-aging degree of the composite geomembrane will be further determined through experiments to provide a basis for the safe operation of the project.