Stenkolonner

Stenkolonner, often referred to as stone columns or soil-stabilized columns, are a ground improvement technique used to increase the bearing capacity and reduce the settlement of soft soils. They are typically constructed by excavating a grid of holes into the weak soil and then backfilling these holes with a granular material, most commonly crushed stone or gravel. Vibratory probes or specialized equipment are used to densify the granular fill as it is placed, creating stiff, load-bearing columns.

The primary function of stenkolonner is to transfer loads from the overlying structure through the weak soil layer to a stronger stratum below. The stone material itself provides a relatively incompressible column, while the densification process helps to compact the surrounding soil, increasing its shear strength. This composite system, consisting of the stone columns and the improved soil, effectively supports foundation loads.

The design of stenkolonner involves determining the optimal spacing, diameter, and type of granular fill based on the properties of the soft soil and the expected loads. Construction is typically rapid and can be carried out with standard equipment. Stenkolonner are a cost-effective solution for a variety of civil engineering projects, including roadways, embankments, building foundations, and port facilities, particularly where soft, compressible soils are present. They help mitigate issues such as excessive settlement, bearing capacity failure, and liquefaction potential.