How are Subsurfaces stone columns different than other aggregate pier systems?
A. Subsurface installs vibro stone columns with a stratacaster vibro rig that combines crowd pressure with high frequency vibration in order to excavate the column hole, thus usually eliminating the need for pre-drilling. Since pre-drilling is not typically required with our service, no spoils are generated. The stone is placed in lifts compacted to design stiffness via the vibro flotation method, and the soil around the outside of the column is densified, thus increasing the overall bearing capacity of the ground.
