Injection is one of the most effective types of repair and restoration work and is widely used for samples and updating brickwork. This technique allows you to prevent further destruction of the wall and is able to significantly extend the service life of the structure.
Causes and consequences of masonry destruction
Violation of the outer and internal integrity of brick masonry occurs for many reasons. The most common of them are the incorrect calculation of the maximum permissible load on the foundation and the violation of the construction technology. In addition, the laying begins to collapse with the inhomogeneity of the soil, the absence of compensatory seams and the close occurrence of the upper aquifers. And among the reasons noted the shrinkage of the foundation, the violation of the depth of it and the deformation processes in the beams arising from the impact of moisture.
Excessive Snow Cover Weight Load. Thick snow reservoir has a significant pressure on the supporting structures, resulting in their weakening and destruction. Often the reason for the start of violation of the integrity of the masonry is the flowing roof. Water penetrates inside brick walls and deractifically acts on the material.
The destruction of masonry occurs gradually, and the voltage arising in the first stage is absolutely unnoticed for a third-party look. Only a professional, who, for the emergence of microcracks, can recognize the beginning of destructive processes. Over time, microcracks grow up, they are connected to each other, form the network and attack the vertical seams, which, in turn, threatens a serious impairment of the building. The most negative consequence of such processes is the unimpeded passage of cold air inside the walls, entailing their freecy.
With the onset of heat, the brick begins to disappear, with the result that the wall reuses and becomes a favorable environment for the appearance of mold. In addition, the decorative coating also begins to crack and peel, and the plaster and ceramic tile – fall off. At the initial stages of the destruction of masonry, when the visible deformation processes are not yet observed, the rusty stains can begin on the walls. This speaks about running corrosion processes on fittings or mortgage parts located inside the wall. To combat the destruction of brick walls, as well as to increase their strength and durability, enjoy the method of injection – consistent injection in the masonry of various materials.
The essence of the method
The essence of the method is that inside the brick wall through the holes done – the sheets – under high pressure supplies certain compositions. Mixture injection occurs through thin pipes equipped with packers (injelers), and is carried out due to the construction syringe or pumps. The mixtures penetrate inside the problem area and fill it all empties, pores and cracks. As a result, a reliable obstacle is created for the penetration of water inside, and the process of destruction stops.
The frozen mass has a moderate reinforcing effect and strengthens the insulating properties of the bases of grounded objects. The method of injection allows to avoid the overhang of capital walls and extend the life of the structure. In addition to repair work, the method is used to arrange intrauterine waterproofing in the construction of the metro tunnels, storage facilities with drinking water, underground parking, pools and sewer collectors.
To restore brickwork, five mixtures are used, differing in the method of application, operational properties and functional purposes.
Mic cement mixtures are widely used for injection and are compounds, the basis of which is a granular cement clinker of fine grinding. This composition occupies all microfucts inside the wall, and after solidification, a substance is formed, similar to its working characteristics with concrete. The advantages of such mixtures is the absolute environmental purity due to the absence in their composition of poisonous and toxic impurities, simplicity of the preparation of solution and low cost. In addition, mic cement mixtures are fully compatible with silicate and polymeric resins, which allows them to use them with a particularly complex repair of the lower row of masonry. The consultation of the material includes a long time to frost. In some cases, it can reach four hours – time depends on the outer temperatures and the consistency of the prepared mixture.
Polyurethane resins are represented by moisture-eating compositions consisting of hydroactive polyurethane, and able to effectively eliminate water leaks. This is due to the ability of the material at the slightest contact with moisture instantly foaming and to form a spongy structure. By the intensity of foaming resin are divided into two types. The first is represented by one-component compositions that can increase their original volume of 50 times. Second-type resins have a two-component performance and are used if necessary for the formation of elastic filling with minimal foaming, but high rigidity. Such formulations are somewhat losing the resins of the first type by the number of foam obtained, they are able to increase their volume of only 20 times.
The advantages of polyurethane resins are high adhesion with most surfaces, the ability to regulate the intensity and polymerization rate, resistance to chemicals and absolute harmlessness to human health. In addition, the material does not give a shrinkage and quite resistant to vibration. Special flaws in polyurethane resins are not marked. The material completely copes with the functions entrusted to it and has only positive feedback.
Epoxy resins are two-component low viscosity mixtures, consisting of polyester polyols and modified isocionate. The material does not contain solvents and polymerizes during the day. The composition is used to seal out the exterior seams of the facade, elimination of cracks, enhancing the masonry and restoration of the integrity of the walls. The advantages of epoxy resins are high adhesive properties, no shrinkage and high mechanical strength. Among the minuses note the high cost of the material and a long time of full polymerization.
Methyl acrylate gels are capable of increasing the volume during frozen, and are used to restore brick walls and increase their waterproofing properties. Injection acrylic is able to update places, and in the early stages of destruction and align the masonry. The pluses of the mixture are good adhesion, resistance to acids and solvents, the ability to operate on wet surfaces, good turnover and low cost of compositions. The minus is the possibility of using funds only at the initial stages of masonry destruction.
With too launched the condition of the brick, the use of methylacrylate will already be ineffective.
Silicate resins are two-component compositions, which are based on liquid glass. The means is resistant to deformation on the shift and perfectly opposes the effects of alkalis, salts and acids. Silicate injection can be made of partial repair of masonry without resorting to her dismantling. The pluses of the material include low cost, fast harmony and no shrinkage. Special flaws in the material are not noted, with the exception of the installation process, which consists of two separate stages, on the first of which it is necessary to fill the cracks with liquid glass, and on the second – calcium chloride.
Technology repair work
Repair of brickwork by injection begins with the preparation of the working surface. From the walls should be removed lubricant, plaster, bitumen, paint, clean it from dirt and dust, and if necessary. Loose cracks with swept edges need to be calculated, and the entire area can be rich in water. Wetting it is better to carry out with the help of a sprayer, and in the case of its absence – by means of a wet rag or sponge.
After the water is completely absorbed into the surface, you can proceed to the formation of the holes. You need to make them at an angle of 60 degrees to the wall of the wall at the calculation of two pieces per fracture. The diameter of the holes is usually 20 mm, and the depth varies from 5 to 15 cm. When filling with a solution of all masonry, the distance between adjacent shpuras should not exceed 15-20 cm. After all the holes are formed, they should also be moistened.
In order for the tubes to be reliably fixed in the holes, it is recommended to strengthen them with cement mortar.
When the composition freezes, you can start filling the cracks using the construction syringe or hand pump. The choice of tool is entirely dependent on the volume and complexity of the work. So, to eliminate small cracks with epoxy resins, it makes no sense to acquire a special pump, while to repair serious destruction of masonry using cement solutions without its help can not do. Downloading is recommended to be performed in the direction of bottom, moving from the center of the working area to its edges. Then, after the time required to frost the composition, it should be carefully removed from the holes fixing devices, to liveraind the deepening with cement mortar and make the finish finish.
The process of injection of brickwork is a unique solution to the problem of restoring collapsing structures. The filling allows you to do without dismantling and partial disassembly of bearing walls, makes it possible to quickly and inexpensively.
See further details.