Subgrade strength, vehicle type, axle loadings, traffic patterns, type of infill material and application (surface or base stabilization) are important factors when selecting the cell type. Contact Presto Geosystems for assistance.

Subgrade strength, vehicle type, axle loadings, traffic patterns and type of infill material are important factors when selecting the cell depth. Contact Presto Geosystems for assistance.

ATRA anchors may be used for temporary or permanent anchoring. ATRA anchors may be required for securing Geoweb in-place based on site conditions, especially for saturated soils or sloped applications. Contact Presto Geosystems for assistance.

The ATRA GFRP Anchor is a glass-fiber reinforced polymer rebar coated with coarse silica sand. The ATRA GFRP Anchor is suitable for environments that may degrade steel rebar. The ATRA GFRP Anchor is impervious to low pH degradation.

Tendons may be required for additional system hold-down, especially when anchors are not used, such as when the system is over a geomembrane.

Specify tendon type in accordance with the design and Contract Documents. Kevlar or polypropylene tendons should be used for concrete infill. Contact Presto Geosystems for recommendations. Tendon type and minimum break strength are as follows:

• TP-31 woven polyester: 700 lbf (3.11 KN)
• TP-67 woven polyester: 1506 lbf (6.70 KN)
• TP-93 woven polyester: 2090 lbf (9.30 KN)
• TK-89 woven Kevlar®: 2000 lbf (8.90 KN)
• TK-133 woven Kevlar®: 3000 lbf (13.34 KN)
• TK-178 woven Kevlar®: 4000 lbf (17.8 KN)
• TPP-44 woven polypropylene: 990 lbf (4.40 KN)

1. Coordinate infill materials with associated Soils and Concrete specifications.
2. Infill materials for load support applications should be predominately granular with a fines content less than 10%. Soils with greater than 10% fines have low permeability and lose strength when wet. A small fraction of fines (less than 10%) increases stability by binding the soil and reducing the void space.
3. Concrete infill is typically used for low water crossing and boat ramps.
4. Engineered infill is typically used to provide the necessary structural strength for load support in areas where vegetation is desired.

A geotextile separation layer is typically recommended for separation between the native soil and infill material. Separation is important to prevent contamination and loss of shear strength of the infill material and to prevent punching or migration of the infill material into the subgrade. The geotextile may also be part of the design to provide additional support. Contact Presto Geosystems for assistance.

Additional subbase materials may be required under the Geoweb layer to support loading or for additional stormwater storage requirements.

A minimum surface wearing course of 2 inches (50 mm) is typically recommended to prevent trafficking directly on top of the Geoweb cell walls. If an asphalt or concrete surface is desired over the Geoweb, a minimum one inch (25 mm) separation layer of infill material shall be provided over the Geoweb to provide minor consolidation of the surface cover and to prevent contact of the asphalt or concrete with the Geoweb cell walls.

A geotextile layer may be required to separate Geoweb infill material from subbase materials or for additional design strength.