Vibro-Concrete Columns are installed where the in-situ soils cannot be improved by compaction, and they are too soft to provide sufficient lateral confinement to resist bulging. Vibro-Concrete Columns are installed to span these soft layers and transfer the load from the surface to an underlying firm layer.

Vibro-Concrete Columns are installed by inserting the vibratory probe, injecting concrete through a side feeder tube to initially form a bottom bulb, and retracting the probe while continuing to inject concrete to form the remainder of the column. The bottom bulb is formed by regenerating the initial concrete lift with the probe. The bulb diameter is dependent upon the stiffness of the underlying layer.