7 Considerations for Composite Geomembrane Installion
1. In the construction, firstly, the sand surface or the clay with a smaller diameter should be used to level the base surface, and then the composite geomembrane lining system are installed. The composite geomembrane should not be stretched too tightly, and the soil embedded in the soil at both ends is corrugated. Finally, a layer of about 10 cm is layered with fine sand or clay on the geomembrane. A 20-30cm block stone (or prefabricated block) is placed as an impact protection layer. During construction, try to avoid the stone directly contact the geomembrane. It is best to carry out the construction of the protective layer while laying the composite geomembrane lining system. The joint of the composite geomembrane lining system and the surrounding structure shall be anchored by expansion bolts and steel strips, and the joints shall be coated with emulsified asphalt (thickness 2mm) to prevent leakage.
2. The contact surface between the composite geomembrane and the supporting material should be leveled to avoid the geomembrane being pierced and lose its anti-seepage effect even with a layer of geotextile. Otherwise, a fine grain cushion should be provided to protect the film from damage.
3. Usually in the corners and deformed sections, the length of the joint between the composite geomembrane lining systems should be as short as possible, except for special requirements, try not to weld in the slope of the slope greater than 1:6 from the top slope or stress concentration area within 1.5 meters.
4. The connection of the composite geomembrane lining system itself, the connection mode of the anti-seepage geomembrane can be summarized into three types, namely, bonding method, welding method and vulcanization method, which are selected according to different raw materials of the anti-seepage geomembrane, and impermeability of all joint seams. All should be inspected to prevent leakage and joint leakage. Automatic HDPE liner welding machine is often ideal equipment to realize HDPE geomembrane welding seams.
5. The connection of the gcomposite geomembrane lining system to the surrounding boundary. The composite geomembrane lining system and the surrounding boundary must be tightly combined. During construction, the anchoring trench can be excavated on the foundation and the bank slope. If the foundation is a shallow sand gravel permeable layer, the gravel should be excavated until the bedrock is poured and then the concrete base is poured. The composite geomembrane lining system is fixed in the concrete. If the foundation is impervious to water, the anchor trench with a depth of 2m and a width of about 4m can be excavated, the composite geomembrane is placed in the trough, and then the clay is densely backfilled; if the foundation is deep, the gravel permeable layer can be impervious by HDPE geomembrane coating. The length is determined according to the calculation. The covering part must be leveled, and the transition layer with a thickness of about 30cm and a maximum diameter of 20mm should be laid. The filter layer is then provided with a protective layer. The periphery of the geomembrane liner should be tightly combined with the impermeable layer on both banks of the bank. The connection between the barrier geomembrane and the anchor trench is determined by the allowable contact osmosis slope of the geomembrane and concrete. Polyvinyl chloride and butyl rubber films can be adhered to the concrete surface with a binder or a dissolving agent, so the embedding length can be shorter, because the HDPE geomembrane can not adhere to the concrete surface, so at least 0.8m of the length of the concrete is embedded.
6. After the composite geomembrane is laid, the walking and moving tools on the composite geomembrane lining system surface should be minimized. Any objects that can cause damage to the impermeable geomembrane should not be placed on the membrane or carried on the membrane to avoid the geomembrane caused accidental damage.
7. Be careful to stack the first layer of mining ores on the composite geomembrane in accordance with the working rules. The mining ores are easily to break the geomembrane even with the upper layer of geotextile.
BPM has been exported many geosynthetic products for mining operations to Africa and South America. With millions of square meters of composite geomembrane lining system installed, BPM geosynthetics has been approved with the highest quality to meet the requirements for the mining industry. We are also providing professional design and installation service.
For the mining projects, GAI LAP testing and third party testing is always required. BPM can fully comply with or exceed the requirement of mining industry standard.