Stablilisation and Reinforcement Technologies

Technologies of consolidation and soil reinforcement are used to increase the mechanical and hydraulic quality of the land with the eventual goal that it can safely withstand more rigorous construction projects.

The aforementioned technologies can be split into the following groups:

• Cement and chemical injections
– Injection technology involves injecting cement and chemical mixtures to saturate the soil porosity and cracks in the rocks. These injections are administered into the ground by drilling holes with specialised tube fitted with valves. The management of the injection process can be manual or automated.

• Jet Grouting
– With this technology, high kinetic energy jets of fluid are injected into the ground to determine factors such as its porosity and solidity, and how it mixes with the injected fluid. The applications for this technique include column foundation treatments, vertical cut-offs, underpinning, consolidation treatments prior to tunnel excavation …

• Artificial soil freezing
– Freezing of the soil temporarily improves soil characteristics and represents an alternative to other conventional technologies. Freezing can be done by via the direct or open cycle method, infusing the soil with liquid nitrogen extracting heat and lowering the temperature to -196o C. The resulting nitrogen is dispersed into the atmosphere, leaving an underground temperature of between -120oC and -60oC. An alternative is the indirect or closed cycle method, which uses a brine solution in the place of liquid nitrogen as the cooling fluid. The brine solution is released into a closed circuit of freezing pipes which navigates the soil in question. The brine solution takes heat from the soil and, now warmer, returns to a refrigeration plant where it is re-cooled and prepared for a new cycle.

• Deep Soil Mixing
– This technique is effected by driving one or more hollow metal rods, each possessing a cutting tool, into the ground and subsequently withdrawing them, resulting in improved soil quality.

• Cutter Soil Mixing (CSM)
– This methodology is obtained by applying hydromill technology to soil mixing. A cutter machine, fitted with drums rotating on a horizontal axis, produces rectangular panels of mixed soil, which optimizes the final technical results and minimizes construction times and wastage.