Everything you need to know about geomembranes

What is a geomembrane?

A geomembrane is a waterproof synthetic sheet made from polymers such as polyethylene (PE), polyvinyl chloride (PVC) or polypropylene (PP). Its main function is to prevent the filtration of liquids and gases in various industrial and environmental applications.

What is a geomembrane used for?

Geomembranes are used in a wide variety of applications due to their impermeable properties and their ability to protect the environment. In civil engineering, they are essential for the construction of reservoirs, canals and tunnels, where they prevent water seepage and ensure structural stability. In mining, they are used to line leaching heaps and tailings ponds, preventing contamination of soil and groundwater with hazardous chemicals. In the agricultural sector, geomembranes are essential for the creation of water reservoirs and efficient irrigation systems, contributing to the conservation of water resources. In addition, in environmental projects, they are used in the construction of landfills and wastewater treatment plants, where they act as barriers to prevent the dispersion of pollutants. Their versatility and efficiency make them an indispensable solution in multiple industrial and environmental sectors.

What are the characteristics of a geomembrane?

Geomembranes have a number of characteristics that make them ideal for use in a variety of industrial and environmental applications.

• Impermeability: Their dense structure prevents the filtration of liquids and gases.
• High chemical resistance: They are able to withstand exposure to corrosive substances and aggressive chemicals.
• Durability: They can withstand extreme conditions, such as UV radiation, extreme temperatures and aggressive environments.
• Flexibility: Some variants such as PVC and LLDPE have greater flexibility, which allows them to better adapt to irregular surfaces.
• Mechanical resistance: Depending on the thickness and type of material, they can withstand mechanical loads and stresses without damage.
• Easy installation and weldability: They can be joined by heat welding techniques to ensure the continuity of the waterproof barrier.

What are the types of geomembrane textures?

Coextruded

• Produced on inflated roll extrusion equipment.
• Controlled cooled rolls.
• Texture pattern that can be controlled and varied.

Its advantage is precisely the variation that can be made to the roughness and texture. It offers increased frictional development and therefore better adhesion. For example, in a seismic event it can be better secured.

In spray

It is produced when a molten polymer is mixed with hot air in spray and sprayed onto the membrane at a certain speed and concentration. It shares many characteristics with coextruded texture such as; the control you have over the texture and roughness.

• The roughness is a little more limited than coextruded.
• Its advantage is less vertical channeling.

Structured

• Produced in flat die extrusion equipment.
• Its shape originates from protuberances or ridges.
• The shape is adjustable; the roughness and texture distribution is handled as desired.
• Its advantage offered is better performance with non-cohesive oils.

The rolls are cooled to determination by contact rolls that have also left an impression in the geomembrane.

For interfaces with higher adhesion, the use of a frictional template is common, although it takes a little longer to install the geosynthetic. However, stability and interface properties that resist slipperiness, leakage and other problems are less likely to occur in design and execution.

What does the durability of geomembranes depend on?

• The durability of the geomembrane depends on the following particularities.
• The type of resin and general materials used in the membrane.
• The knowledge of the design engineer in the selection and specification of the high density polyethylene, as well as the liner for minimum stress in slopes, ditches, perforations and anchor grooves.
• The knowledge of the design engineer in the design of the system that accommodates the installation to the operating conditions.
• The knowledge of the design engineer in the proper specification of point protection for the geomembrane.
• The ability of the manufacturer to produce a consistently homogeneous material with a minimum of errors and with sufficient anti-rust additives.
• The smoothness, uniformity and density of the subgrade.
• The quality of installation. The elimination or minimum wrinkles, intimate contact with the subgrade, joints, penetrations, minimum welds and minimum shear stress on slopes.
• Layer distribution.
• Distribution of the first layer of waste.
• Construction quality control.

Geomembranes are essential solutions for projects requiring waterproofing and environmental protection. Their choice depends on factors such as material, thickness and conditions of use. Having a reliable and experienced geosynthetics supplier will guarantee the success of your project.

At SAI, we are experts in the installation of high quality geomembranes for various applications. Contact us for specialized advice and guarantee the best solution for your project.