HDPE Geomembranes | GRI GM13 | Smooth & Textured

High-Density Polyethylene (HDPE) geomembranes, are synthetic liners widely recognized for their exceptional durability, chemical resistance, and impermeability. Made from high-quality HDPE resin and enhanced with additives like carbon black for UV stability, these geomembranes are manufactured to meet stringent international standards such as GRI-GM13, GB/T 17643 and EN 13361, ensuring consistent quality and performance. Available in both smooth and textured surfaces, HDPE geomembranes cater to diverse project requirements. At Metalsin, we specialize in supplying high-performance HDPE geomembranes that comply with global standards, tailored to your specific engineering and environmental needs.

GRI-GM13

The HDPE geomembrane with smooth surfaces in production process.

GRI-GM13 is a standard specification developed by the Geosynthetic Research Institute (GRI) that defines the test methods, properties, and testing frequencies for High-Density Polyethylene (HDPE) geomembranes, including both smooth and textured types. It sets minimum requirements for physical, mechanical, and chemical properties such as tensile strength, tear resistance, puncture resistance, stress crack resistance, carbon black content, and oxidative induction time (OIT). The specification ensures manufacturing quality control (MQC) and references a series of ASTM standards for testing, focusing on properties critical to geomembrane performance in applications like landfills, water containment, and environmental protection. Further, the international standards equivalent to GRI-GM13 include China’s GB/T 17643 and EU’s EN 13361.

Smooth & Textured

Smooth HDPE geomembranes feature a flat, mirror-like surface that reflects light, offering a bright and clean appearance. They have a low friction coefficient, making them ideal for flat or low-slope areas such as landfill liners, reservoirs, and irrigation ponds. Their smooth surface facilitates easy installation and welding, though additional anchoring may be required on steep slopes. Smooth geomembranes exhibit high tensile strength and elongation but are slightly less resistant to environmental stress cracking compared to textured variants. They are cost-effective due to simpler manufacturing processes and are commonly used in water management and decorative applications like landscape ponds.

A roll of HDPE geomembrane with textured sufaces.

Textured HDPE geomembranes have a rough surface with raised patterns or asperities, created through co-extrusion or spray-texturing processes. This texture provides a high friction coefficient, enhancing stability and grip on steep slopes, embankments, and complex terrains. They are particularly suited for applications requiring superior shear resistance, such as landfill slopes, tailings ponds, and tunnel linings. Textured geomembranes offer better environmental stress crack resistance and elongation, making them more durable in challenging environments. However, their complex manufacturing process results in higher costs, typically 10%-20% more than smooth geomembranes. They are the preferred choice for projects demanding high friction and stability.

Technical Specifications

• Material Composition: Made from high-density polyethylene (HDPE) resin with a density of ≥ 0.940 g/cm³, typically containing 2.0-3.0% carbon black for UV resistance.
• Dimensions: Thickness ranges from 0.5 mm to 3.0 mm, with tolerances of ±10% for smooth and ±15% for textured geomembranes. The supply width of HDPE geomembranes typically ranges from 2 meters to 7 meters, and the length ranges from 50 meters to 100 meters.
• Mechanical Properties: Tensile Strength: Minimum 25 MPa (MD and CMD); Elongation at Break: Minimum 600%; Tear Resistance: Minimum 110 N/mm; Puncture Resistance: Minimum 320 N.
• Chemical Stability: Resistant to acids, alkalis, and organic solvents, suitable for harsh environments like landfills and chemical containment. Environmental Stress Crack Resistance (ESCR): Minimum 500 hours (per ASTM D5397). Oxidative Induction Time (OIT): Minimum 100 minutes (standard OIT) or 400 minutes (high-pressure OIT) to ensure long-term durability.
• HDPE geomembranes exhibit excellent UV resistance due to the inclusion of 2.0-3.0% carbon black in their formulation, which protects against degradation from prolonged sunlight exposure. They are tested under ASTM D7238 to ensure durability, with textured geomembranes potentially offering enhanced UV stability due to their increased surface area. This UV resistance ensures long-term performance in outdoor applications like landfills, reservoirs, and exposed containment systems.

Manufacturing Process of HDPE Geomembranes

The production of HDPE geomembranes begins with the preparation of raw materials, primarily high-density polyethylene (HDPE) resin, which is mixed with additives such as carbon black, antioxidants, UV stabilizers, and colorants to enhance durability and performance. The mixture is fed into an extruder, where it is melted and homogenized under high temperature and pressure. The molten HDPE is then extruded through a flat die to form a continuous sheet, which is cooled using rollers or water baths to solidify. The cooled sheet is trimmed to the desired width and length, and surface treatments like calendering may be applied to achieve a smooth or textured finish. Finally, the geomembrane is wound onto rolls, inspected for quality, and packaged for storage and transportation.

Applications & Installation

HDPE geomembranes are widely used in landfills for lining and capping to prevent leachate contamination, in water containment systems such as reservoirs, ponds, and canals to ensure water retention, and in mining for tailings storage and heap leach pads. They are also employed in agriculture for irrigation ponds and in environmental protection projects like hazardous waste containment. Their versatility, durability, and impermeability make them essential in civil engineering, wastewater treatment, and industrial applications.

The HDPE geomembrane lined aquaculture pond.

The installation of HDPE geomembranes involves surface preparation, laying a protective geotextile layer, unrolling and positioning the geomembrane, heat-welding seams, and conducting seam testing to ensure integrity. The geomembrane is then anchored at the edges, covered with a protective layer to prevent UV and mechanical damage, and inspected for defects. This process ensures a durable, leak-proof barrier for applications like landfills, reservoirs, and mining operations, adhering to ASTM and GRI standards.