Vibro concrete columns transfer loads through weak strata to a firm underlying stratum, using high modulus concrete columns constructed with a bottom-feed, down-hole vibratory probe. This technique has generally been replaced with rigid inclusions.
- Increase bearing capacity
- Decrease settlement
- Increase global stability
A bottom-feed, down-hole vibratory probe is advanced through the weak strata to the underlying firm stratum. Granular bearing soils are densified by the vibrator. Concrete is then pumped through the bottom-feed tremie tube. The vibrator is raised and lowered several times within the bearing depth to construct an expanded base. The vibrator is then raised to the surface as concrete fills the void created by the vibrator during extraction. Typically, the vibrator also re-penetrates the top of the column to construct an enlarged head, which can be overlain by a geogrid reinforced soil relieving platform.