Geosynthetic clay liner (GCL) is a geosynthetic material for anti-seepage in various applications. It contains highly expansive Sodium-based bentonite between composite geotextile and non-woven fabric. The needle-punched pad creates small fiber spaces. Bentonite particles stay in the pad when wet. This material forms a uniform, high-density colloidal waterproof layer to prevent leakage effectively.
Mechanism of Geosynthetic Clay Liner
Geosynthetic clay liner (GCL) blocks leakage paths in earth dams with impermeable plastic film. Its high tensile strength and elongation resist water pressure and adapt to dam deformation. Non-woven fabric, a polymer short fiber, enhances GCL through needle punching or thermobonding for high tensile strength and extensibility. Combining GCL with plastic film boosts the latter’s tensile strength and puncture resistance while the rough non-woven surface increases friction at contact points.
Characteristics of Geosynthetic Clay Liner
The geosynthetic clay liner GCL also has the following characteristics.
Compactness.
Sodium bentonite forms a high-density diaphragm under water pressure. When the thickness is about 3mm, its water permeability is less than &×10^-11 m/sec. This is equivalent to 100 times the compactness of a 30cm thick clay layer and offers strong self-retaining properties.
Permanent waterproof performance.
Sodium bentonite is a natural inorganic material. Even after long periods or environmental changes, it does not age or corrode. Thus, its waterproof performance remains long-lasting.
Simple construction and short construction period.
Compared to other waterproof materials, GCL’s construction is simpler. It doesn’t require heating or pasting. Just use bentonite powder, nails, washers for connection and fixation. No special inspection is needed after construction. If waterproof defects are found, it’s easy to repair. GCL has the shortest construction period among existing waterproof materials.
Not affected by temperature.
It will not be brittle under cold weather conditions.
Integration.
Sodium bentonite has a 20-28 times expansion capacity when it encounters water. Even if the concrete structure vibrates and settles, the bentonite in GCL can repair cracks on the concrete surface within 2mm.
Green.
Bentonite is a natural inorganic material. It is harmless and non-toxic to the human body. It has no special impact on the environment. Its environmental performance is good.
Case Study Of Geosynthetic Clay Liner GCL
The geosynthetic clay liner (GCL) is suitable for municipal landfills. It is also ideal for water conservancy projects and environmental protection. Additionally, GCL is used in artificial lakes and for building underground waterproofing and anti-seepage. It can be constructed at negative temperatures (-20℃), unlike traditional waterproof materials. GCL can also be installed on damp surfaces without prior drying. However, it cannot be used in rain or snow, nor in areas with strong acids or alkalis due to potential damage. Bentonite’s inorganic nature makes it more durable than organic waterproof materials. A client recently emailed us about a bid for a reservoir project, requesting 30,000 square meters of GCL. We asked for specific requirements, and the client was pleased and invited us to review their sample.
Specification of Geosynthetic clay liner GCL for water storage project in Thailand
- Roll size – 5.8m*30m
- GCL Specification – 4350g/sqm
- Quantity – 30000sqm
Construction method of GCL
- The weight of the GCL blanket material is relatively large, so it is advisable to use a shovel machine to carry and lay the waterproof blanket hoisting tool.
- The geosynthetic clay liner material is connected by lap joint.
- When laying the geosynthetic clay liner on a slope greater than 10%, the number of overlaps along the length of the slope should be minimized, and the bentonite pad on the slope must exceed the foot line of the slope by more than 1500mm.
- Any equipment used to lay the geosynthetic clay linert cannot be driven on the already laid geosynthetic material. When installing the geosynthetics clay liner, the outdoor air temperature cannot be lower than 0°C or higher than 40°C.
- The edges of all exposed geosynthetic clay liner must be immediately pressed. Use sandbags or other heavy objects to secure them. This prevents the geosynthetic clay liner from being blown by the wind or pulled out of the surrounding anchoring ditch.
- The laying method of the geosynthetic clay liner must ensure direct contact with the foundation. This eliminates wrinkles in the bentonite waterproof blanket. Proper installation is crucial for effective performance.
- The geosynthetics clay liner equipment must be approved by the supervision engineer before it can be used. Unprotected razors or “quick knives” are not allowed. I. The construction equipment that may damage the bentonite blanket cannot directly act on the bentonite blanket.
- When laying the bentonite blanket, minimize drag on the foundation. This avoids damage to the contact surface between the bentonite blanket and the ground. Proper handling ensures the integrity of the waterproofing system.
About GEOSINCERE
As the professional geotextile and geosynthetics manufacturer and wholesaler, GEOSINCERE is always committed to geotextile research and development, manufacturing and installation services. We can provide our customers with most extensive lines of geotextiles and geomembranes for civil, mining, environmental and aquaculture engineering applications. GEOSINCERE brand geotextiles and other geosynthetics products and solutions can meet your requirements by our solid technologies, innovative engineering solutions and excellent customer services. Hope to be your partner.
Our main innovative, high quality products include geotextiles, geomembranes, geogrids, geocells, geosynthetic clay Liner, and drainage boards, etc al. GEOSINCERE customers are from more than 100 countries. If you have any questions or inquiries, please fill and submit the following form, we will reply as soon as possible.
