Ground stabilization and geotechnical injections

Geotechnical injections are a modern, trenchless technology used to improve the load-bearing capacity of the soil. They are performed beneath existing structures whose stability has been compromised or prior to a planned change in their use. When performed correctly, this procedure effectively stops structural settlement, fills voids, and seals the soil.

The main causes of soil degradation:

The leaching of soil particles caused by failures in the water and sewer systems, vibrations caused by traffic or construction work, errors in geological surveys, a rise in the groundwater level, and natural settlement processes.

Classification of methods based on their nature:

Depending on how they affect the substrate structure, we distinguish the following types of injection:

• Filling and consolidating —the material penetrates the natural pores and cracks in the soil, binding loose particles into a monolithic, hard block.
• Expanding (lifting) – the product rapidly expands beneath the foundation, generating a controlled force that allows for precise floor lifting of settled floors or walls.

Important: Accurate assessment of soil and groundwater conditions and the depth of the foundation is essential for determining the injection pressure and the setting time of the material.

Selection of grouting materials

Geotechnical injections use very high-strength grouts with varying setting times, selected based on the type of soil:

• Mineral suspensions: Most commonly used to fill post-mining voids and caverns, and to consolidate loose, coarse-grained, and stony soils.
• Geopolymers and polyurethane resins: Widely used for rapid stabilization and lifting of foundations due to their immediate strength gain, high foaming power, and resistance to moisture.