In many areas, but most of all in construction, reliable solid soils are very important and necessary. This is a guarantee that any building, from a private house to a large production workshop, will maintain its integrity for many decades. Unfortunately, the place allotted for construction is not always stable. Being close to the groundwater surface swamps the soil, making it unsuitable for the construction of even small buildings.
Soil stabilization methods
There are several ways to stabilize soil, fix it, reduce compressibility and increase strength. One of them is to increase the cohesion between particles without disturbing the soil structure. Most popular methods:
- Soil claying.
- Silicization of soils.
- Cementation.
- Thermization.
- Electrochemicalization.
The choice of a specific method depends on the type of soil. Most often, silicification is used to strengthen the soil as the simplest option for solving such a serious issue. What is thismethod, what are its advantages and features? More on that later.
Silicization of soils
Important detail: soils impregnated with oil products or resins are not subject to silicification.
Using this method, it is possible to strengthen both water-saturated soils and dry sands, microporous subsidence and other types of bulk soils. The technology of soil silicification is very simple: to make the soil more reliable and durable, a certain substance is injected into it. It cements the pores in the soil, due to which the bond between the particles increases and the soil becomes much stronger.
On sandy soils and loess, the single solution method is usually used. If sandy soils are saturated with moisture or are quicksand, their condition can only be changed using the two-solution silicification method. It is possible to fix soils with silicification only if the base has a filtration coefficient of 3-78 m3/day.
What is special? The peculiarity of soil silicization is that, penetrating into the soil, substances envelop small components, gluing and binding them. To complete the whole process, holes are prepared in the ground or wells are drilled. After that, a solution is prepared in the required volume and pumped into the soil through injection pumps.
One solution silicification
On silty sands and other types of unstable soils, it is the one-solution method of soil silicification that is used. To do this, in the soil of the desired piece of landserve a solution of liquid glass mixed with sulfuric or phosphoric acid.
Note: earlier, ammonium sulphate could serve as another component. But it has been banned by new environmental service regulations.
After single-solution silicification, the soil becomes more stable, but its strength is not enough for the construction of large structures.
One liquid glass can also serve as a stabilizing substance. This option is used on loess planting soils. A reaction occurs between liquid glass and water-soluble s alts of the soil, resulting in the formation of a gel.
Two solution method
Two-solution silicification of soils differs from the previous version in that the selected components are injected into the soil not simultaneously, but in turn: first liquid glass, and then calcium chloride. After a chemical reaction, a new substance is formed. This is silica gel. Its main quality is intensive hardening, which is carried out during the first day. Further, the hardening rate decreases significantly, and it ends in 80-90 days. During this time, the strength of the soil increases significantly and reaches at least 4.5 MPa.
Main features of the two-solution method
Silikatization of soils by this method has its advantages and disadvantages. Undeniable benefits:
- The ability to fix the soil at a sufficiently large radius from the well.
- No need to usespecial machinery, sophisticated equipment.
- Possibility to significantly improve soil quality.
Unfortunately, there are also disadvantages, but they are few:
- Costly – Chemical components are not cheap.
- The hardening process takes a long time.
When is silicification recommended?
Fixation of soils with silicification is recommended in the following cases:
- During the construction of highways.
- In the construction of industrial, warehouse and office premises, private houses, infrastructure and other facilities.
- When laying railway lines.
- During the construction of hydraulic structures.
- When it is necessary to compact loess soils.
- For strengthening worked out soils, etc.
The use of the two-mortar method guarantees the strength of the soil, so that buildings and other structures will not shrink, crack or heel.
What does soil silicification give?
Silikatization of soils allows:
- Increase the bearing capacity of the soil under the foundations of the foundations of structures and buildings.
- Compact decompacted soils, strengthen it during the repair of the foundation under buildings and structures.
- Consolidate the base soil in cases where it is planned to lay utilities or repair them. It is recommended to carry out this procedure on decompacted soils and when excavating pits.
- Eliminateor prevent unpredictable shrinkage of foundations on decompacted soils.
- Strengthen the slopes of the pits.
- Set up an impervious curtain.
- Repair the tilt of an emergency building or structure.
