Three methods of splicing impermeable membrane on site
There are three methods for splicing impermeable membranes on site: overlap method, the bonding method, and thermal welding method.
After the two rolls of the impermeable wholesale environmental geomembrane are unfolded, overlap 20 ~ 40 cm along the wide side. This method is widely used in small and medium-sized channels and is simple, labor-saving, and material-saving. However, if the seams do not overlap well, water leaks easily. For example, the large fly ash storage warehouses in the former Soviet Union and the Jiaozhou Youth Reservoir in Qingdao, Shandong have serious leakage problems, causing rework and a huge waste of manpower and material resources.
1. Solvent bonding method: apply a chemical solvent on the overlapping surface of an impermeable film with a bonding width of 5-10 cm to form a uniform bonding layer with a certain thickness, and roll it with a bonding roller until the binding is firm.
2. Gluing method: Apply chemical glue on the overlapping surface, and then roll it into a whole with a rubber wheel. At present, many domestic manufacturers have developed corresponding adhesives—polyethylene adhesives based on the characteristics of anti-seepage materials, and have been applied in many anti-seepage projects with good results.
The problems with this bonding method are ①Generally, it needs to be done manually, and sometimes the joint surface needs to be properly treated. The bonding time of the adhesive is greatly affected by the temperature; ②Most chemical solvents and adhesives have pungent odors, There are still problems in shear strength, anti-aging ability and adaptability to the water environment, so this method is generally only suitable for small projects.
The principle of thermal welding is to transfer heat to the surface of the geomembrane produced by LDPE geomembrane manufacturers at the joint by a welding machine to melt it, and the molecules infiltrate and exchange within the melting range and dissolve into a whole, and then pressurize the welding part through a roller so that the melting area is not Obvious interface. The method is convenient to use and easy to master and is very suitable for long straight seams and thermoplastic anti-seepage materials.