Geomembrane FAQs

1.What is a geomembrane used for?

Geomembranes primarily serve as low-permeability barriers and are widely utilized in the base lining and capping of landfills, tailings dam containment, and the construction of landscape ponds and water reservoirs. In municipal and transportation engineering, they are frequently employed for tunnel waterproofing, basement damp-proofing, and roadbed reinforcement to prevent the seepage of liquids and hazardous substances, thereby safeguarding the safety of groundwater environments.

2. HDPE vs LLDPE vs PVC geomembrane: which should I choose?

Thanks to its exceptional chemical stability and UV resistance, HDPE is the preferred choice for long-term projects such as landfills. LLDPE offers superior flexibility and elongation properties, making it suitable for complex terrains and irregularly shaped containment applications. PVC, known for its excellent conformability, is frequently used in non-exposed applications—such as tunnels or underground structures—for leak repair and sealing purposes.

3. What thickness of geomembrane do I need for a pond or landfill liner?

The selection of thickness must be based on pressure testing results and specific geological conditions. Typically, a minimum thickness of 0.75 mm (30 mil) is recommended for landscape ponds. For high-risk projects such as landfills, the GRI-GM13 standard recommends a base liner thickness of no less than 1.5 mm (60 mil). If the site involves sharp rock fragments or is subject to extremely high hydrostatic pressure, the thickness should be increased to 2.0 mm, accompanied by the use of a protective geotextile layer.

4. What QA/QC documents should a geomembrane manufacturer provide?

Manufacturers are required to provide a Material Test Report (MTR) that includes batch tracking records and covers key performance indicators such as tensile properties, tear strength, carbon black content, and OIT (Oxidative Induction Time). Additionally, the documentation must include a Certificate of Conformity (COC) adhering to ISO/ASTM standards, reports on the raw resin materials used, and records of in-process monitoring data collected during manufacturing.

5. How are geomembrane seams welded and tested?

Dual-track thermal fusion welding is the industry-standard method; this process utilizes extrusion or a hot wedge to create a pair of parallel weld seams, leaving an air channel between them. Testing is categorized into non-destructive methods (such as vacuum box testing or air pressure testing, which ensure stable pressure within the air channel) and destructive methods (such as peel and shear tests), ensuring that the weld strength meets or exceeds 90% of the base material's standard value.

6. What is the service life of an HDPE geomembrane liner?

In a buried environment, a compliant HDPE geomembrane has a theoretical service life exceeding 100 years at a constant temperature of 20°C. When used in exposed applications, the service life is influenced by ultraviolet radiation and typically ranges between 20 and 30 years. Its durability depends primarily on the antioxidant content within its formulation and the rate at which these antioxidants are depleted under environmental stress.

Geomembrane Types

The HDPE geomembrane is the most widely used impermeable liner in the industry due to its outstanding chemical resistance and UV stability. It provides a highly durable barrier for large-scale environmental containment projects requiring long-term performance.

For projects that demand superior flexibility and multi-axial elongation, the LLDPE geomembrane is an excellent choice. This material is particularly effective in applications where the liner must conform to irregular surfaces or withstand significant differential settlement.

An EVA geomembrane is highly regarded for its exceptional flexibility and superior low-temperature impact resistance. This material is an ideal choice for specialized waterproofing projects, such as tunnel construction and underground infrastructure, where high elasticity and stress-crack resistance are required.

When a project requires the combined benefits of a moisture barrier and mechanical reinforcement, a composite geomembrane liner is the optimal solution. This integrated material features a geomembrane bonded with a geotextile to enhance puncture resistance and increase interface friction.

Common Geomembrane Applications

• High-performance landfill liners are essential for modern waste management systems to prevent hazardous leachate from contaminating groundwater.

• Durable pond liners are widely used in aquaculture and decorative water features to maintain consistent water levels and ensure seepage control.

• Reliable reservoir liners provide a secure containment solution for agricultural irrigation and industrial water storage, preventing valuable water loss.

Main Products