Agru Australia

Super Gripnet® Liner

AGRU’s Super Gripnet® two resin types, HDPE and LLDPE, support projects where drainage and high interface friction, as well as cost savings, are critical.

Overview

As a replacement and improvement to traditional geocomposite drainage products overlying textured geomembrane, facility owners capitalize on the increased performance and decreased costs that using Super Gripnet® provides. This is evident from over 150,000,000 square feet of Integrated Drainage System – IDS installation across the United States and beyond. 

HDPE and LLDPE Super Gripnet® applications include projects where containment, drainage, interface friction and economic dynamics are critical. These projects include landfill closures, containment facilities, oil & gas applications, mining reclamation projects, to name a few. The structured IDS geomembrane is manufactured by continuous horizontal flat die extrusion into profile rollers, which produces the final structured surface of drainage studs and spikes. This manufacturing process provides a smooth edge for on-site welding and a consistent core thickness, which provides industry leading geomembrane physical properties. This IDS product results in environmental containment, higher interface friction capabilities, consistent drain capacity and decreased project costs.

Our engineered profile rollers provide the structured surface with a 130 mil/3.3 mm studded drain surface on the top side and 175 mil/4.45 mm spiked friction surface on the bottom side. The 23 feet/7 meter wide rolls of finished product include a smooth edge on both sides of the roll for ease of thermal welding in the field. Due to the moulded structure, core thickness variation is dramatically reduced as compared with blown film textured sheets, so the mechanical properties of the sheet are greatly superior. In addition, the consistent high-profile spike surface ensures optimum interface friction characteristics at any point on the sheet surface and provides greater factor of safety values.

Technical Aspects

Super Gripnet’s structure includes a 3.3 millimeter high studded drain surface on the top side and 4.45 millimeter high spiked friction surface on the bottom side. The 7 meters wide rolls of finished product include a smooth edge on both sides of the roll for ease of thermal welding in the field. Due to the molded structure, core thickness does not vary as with blown-film textured sheets, so the mechanical properties of the sheet are not affected. In addition, the consistent high-profile texture ensures optimum interface friction characteristics at any point on the sheet surface.

Interface Shear – Cap Loading Conditions – ASTM D 5321

SOIL/GRIP LINER SURFACEPLD
Coarse Sand35°31°
Glacial Till38°34°
Silty Sand28°26°
Non-Woven GT31°26°
SOIL/DRAIN LINER SURFACE WITH GTPLD
Coarse Sand30°30°

P = Maximum or Peak Interface Shear Value in degrees; LD = Large Displacement Interface Shear Value in degrees; GT = Geotextile

The top surface integral drainage studs are spaced in a diamond pattern with 12.5 millimeters spacing, and a lter/protection geotextile is then placed on the drain profile. The geotextile is heat set on one side, placed against the drain structure, to reduce intrusion into the drain. Large-scale ow rate testing, overlying soils and expected normal loads result in high planar ow rates.

The bottom spiked friction surface with its high spikes and patterned texture provides maximum interface friction and a high factor of safety against sliding.