Geogrids are made by punching and drawing polyolefin sheet, by knitting or weaving polyester yarn and coating it, or by welding drawn polymer straps. Aggregate particles poke through the apertures and lock in, so the grid carries tension and restrains sideways movement of the fill. They are grouped as uniaxial, biaxial or triaxial by how their strength and stiffness are distributed.
Two layers of geogrid under the crane pad, and the stone has to be inch-and-a-half so it locks in.
Check the aggregate gradation against the aperture size before placement; interlock is what makes a grid work.
Also heard as
- grid
- geogrids
Related terms
Uniaxial geogrid
Geogrid with its strength concentrated in one direction, used to reinforce walls and steep slopes.
Biaxial geogrid
Geogrid with similar strength in both directions, used mainly to stabilize aggregate bases over soft ground.
Triaxial geogrid
Geogrid with triangular apertures that gives fairly even stiffness in every direction across its plane.
Aperture
Open space between the ribs of a geogrid or between the strands of a woven geotextile.
Reinforcement
Using the tensile strength of a geosynthetic to hold soil together so it can stand steeper or carry more load.