Geosynthetic Clay Liner

Geosynthetic clay liner (GCL) are needle-punched reinforced composites that combine two durable geotextile outer layers with a uniform layer of low-permeability sodium bentonite clay. Once hydrated, GCLs swell to form a hydraulic barrier.

These are a popular choice for earthen spill containment berms, landfill lining and capping, canals, reservoirs, and adorning ponds. They are also the perfect solution for preventing harmful seepage in oil and gas tanks.

High Hydraulic Performance

A geosynthetic clay liner (GCL) is a prefabricated layer consisting of two layers of needle punched, physically bonded or stitched geotextiles sandwiching a thick layer of sodium bentonite. Bentonite is a fine-grained, absorbent, montmorillonite-based clay that swells on wetting. GCLs have a wide range of applications. They are used as secondary liners for landfills; as primary liners in gas and vapor seals, soil stabilization projects, ground engineering, wastewater treatment, and agriculture; and as waterproofing.

Many containment barrier systems must be designed to control both advective and diffusive contaminant transport, resulting in a complex set of requirements for a single liner. Geosynthetic clay liners are a solution to this challenge, as they offer several benefits over traditional compacted clay barriers. These include easy installation, high hydraulic performance, and resistance to variable weather conditions.

Landfills must be built with proper containment and protection measures to prevent the release of solid and liquid waste materials into the environment. This is particularly important when dealing with hazardous wastes, which must be contained and disposed of in accordance with environmental laws. Geosynthetic clay liners can help ensure that landfills are safe and clean for years to come.

In addition, GCLs can also be used as liners in spill containment berms to protect the surrounding soil from contamination. This is particularly beneficial when dealing with toxic chemicals, such as petroleum or solvents.

Resistant to Variable Weather Conditions

Often used as replacements for compacted clay liners or as components of composite liner systems, Geosynthetic clay liners are needle-punched reinforced composites consisting of multiple layers of durable geotextiles and a low permeability Geosynthetic clay liner sodium bentonite core. The bentonite clay swells on contact with water, sealing the area and reducing the hydraulic conductivity of the liner system. This self-sealing capability allows GCLs to withstand the effects of variable weather conditions.

Sodium bentonite is a type of montmorillonite mineral that has the unique property of swelling upon contact with water. It expands to 15-17 times its original volume, forming a high-density impermeable pad that prevents fluid leakage from the site. During manufacturing, this bentonite is packed between special composite geotextiles and non-woven fabrics. This ensures that the shear strength of the system is strong enough to resist a wide range of environmental stresses.

To test this shear strength, internal and interface direct shear tests were conducted on eight different GCL/GMX composite systems with varying normal stress levels. Results showed that increasing normal stress transitioned the failure mode from complete interface/internal to partial interface/internal and non woven geotextile fabric manufacturers then to internal shear failure. These findings suggest that shear performance of GCLs is affected by the combination of GCL layer thickness and the amount of GMX in the system. The best combination of these factors will provide the maximum level of protection against external forces.

Easy Installation

Geosynthetic clay liner or GCLs are a highly efficient containment barrier used in various environmental engineering projects. They are fabricated by sandwiching a layer of sodium bentonite between two layers of geotextiles, which protects the liner from damage or physical breakdown in harsh environments. The bentonite’s high swelling capacity and low permeability help to create an impermeable barrier that offers a high level of hydraulic performance.

This is especially important in landfills where the liner acts as an impermeability barrier to prevent contaminants from migrating into groundwater or other areas of the site. This minimizes the amount of waste that needs to be removed and transported, reducing environmental impact. Additionally, GCLs are a quick and cost-effective alternative to compacted clay liners.

The mechanical properties of GCLs also contribute to their long-term performance, including the ability to withstand shear and puncture forces without degrading or leaking. These factors should be considered during design and installation to ensure the liner is able to perform under demanding conditions.

GCLs are manufactured at factory units with stringent quality control measures to ensure optimal performance, and are available in a variety of dimensions and thicknesses. They are delivered to the project site pre-fabricated for easy installation by unrolling and overlapping. This saves time and money by eliminating the need for heavy equipment and lengthy construction periods.

Cost-Effective

In comparison with some other types of liners, such as geomembrane, Geosynthetic clay liner is less expensive to install. This is because it doesn’t require welding to join sections together. Instead, GCLs are simply overlapped together. This is a great advantage when you need to cover a large area with the liner.

Another benefit of GCLs is that they are more environmentally friendly than other materials, such as asphalt and concrete. This is because they use fewer natural resources, and they are manufactured in factory units, which ensures quality control and stringent testing measures. Furthermore, GCLs are also easier to deliver and construct. They are prefabricated and can be delivered to site in rolls, which means they do not require heavy construction vehicles or specialized equipment for installation.

GCLs are especially useful for lining landfill cells, as well as capping landfill cells and enclosing contaminated soil. They are a great alternative to traditional compacted clay liners and offer superior hydraulic performance and resilience to changing weather conditions.

GCLs can also be used to add an extra layer of protection to spill containment berms. This helps prevent rough terrain from poking through the lining and damaging the surrounding environment. Furthermore, it can help protect the water supply in case of a spill. This is why they are frequently used in petroleum and chemical storage tanks.