The rig runs a deep vibrator, 130 horsepower, hanging from a crane. It punches through fill and soft clay. In Columbus, we use vibro-replacement stone columns because the native ground won't hold a building on its own. The glacial lake plain left compressible clays across Franklin County. These soils consolidate under load. They settle. Stone columns change that equation by creating stiff, draining inclusions in the weak matrix. Before mobilization, the design phase determines column diameter, spacing, and depth based on the load and the soil profile. We often pair this with CPT testing to get continuous stratigraphy without disturbing the sample, especially where the soft zone depth varies across the site.
A 20 percent area replacement with stone columns can cut total settlement by half versus untreated ground, and the gain in bearing capacity often exceeds 100 percent.
