Foundation Reinforcement

Reinforcement of a building's foundation is carried out to strengthen and increase its load-bearing capacity. This is one of the most labor-intensive and complex tasks during building repair, involving a comprehensive set of construction works and requiring precise identification of the main causes behind defects in load-bearing structures.

Factors triggering the need for foundation reinforcement

Experts identify several key reasons that may lead to foundation damage and require reinforcement:

• design errors made during the foundation planning stage;
• violation of construction techniques during foundation laying;
• improper building operation;
• changes in soil characteristics such as groundwater level, frost heave, moisture absorption, and soil swelling;
• vibrational impacts on the foundation or installation of utility lines.

Moreover, foundation reinforcement is especially critical in large cities, where owners of buildings with commercial appeal often consider adding extra floors, significantly increasing the load on the foundation.

Methods of foundation reinforcement

From a design perspective, reinforcing a foundation is several times more complex than constructing new structures. This is because, in this case, not only existing deformations but also the operating conditions of each specific structure must be considered. The choice of a particular technique depends on the type and condition of the existing foundation, as well as the building’s structure and local geological conditions.

When deformations occur due to soil settlement or compaction loss, soil strengthening is advisable. This complex process involves creating artificial additional bonds between soil particles.

Increased strength is achieved by injecting various hardening solutions. Common methods include silicatization, bituminization, cementation, and resinification.

This technique involves drilling small-diameter injection wells through which special mixtures are injected under high pressure into the surrounding soil and foundation body. This process increases and strengthens the foundation’s bearing area, thereby enhancing the overall load-bearing capacity of the structure.

For reinforcing strip-type foundations, the method of replacing the old base with a new monolithic foundation slab is typically used. The old foundation is unloaded, specific sections are exposed, and new monolithic sections are installed under load-bearing walls.

When load significantly increases, a common solution is installing additional foundations in the form of bored-injection piles, which can reach up to 20 meters in length. Boreholes for such foundations can be drilled not only through the old foundation but also adjacent to it. These piles are reinforced and filled with a special concrete mix known for its water retention and high elasticity.