Concept
Compacted soil is stronger than un-compacted (loose) soil.
Soil Compaction
Geotechnically
It is well understood that compacted soil is superior to loose soil when structural support is required.
Compacted soil has very little space between the particles, this allows it to resist forces and bear heavy loads.
Loose soil is filled with air which gives the particles lots of room to move around, it is not reliable to bear a load.
Soil Compression through torque
Torque is the twisting force you apply when driving in a screw. The treads of the screw pull the screw down into the wood. When the head of the screw meets the surface of the wood it begins to compress the wood.
Similarly, screwing the pile into the ground pulls the Earth Grip down and causes the soil to compact.
This is the “Grip” in Earth Grip. The design actively employs the surrounding soil, causing it to become part of the stability of the entire system.
The amount for force that the helical pile pulls the Earth Grip downward depends on the type of helical pile being used, but for the common helical piles you’ll find at Home Depot with 1 1/2″ diameter shaft and 6″ diameter helical flight, you’ll easily get an axial tension of 6500lbs in compacted soil, (that’s the downward pressure on the Earth Grip)