Concrete placementLaying of concrete in Moscow and the Moscow region — one of the directions of work of the SNEP-Stroy company having a wide experience in the field of the device of industrial floors and bulk floor coverings. Laying of concrete is always an extremely important stage of installation of polymer coatings and, especially, industrial concrete floors, since in the latter case, the concrete base with a hardened top layer serves as a direct floor covering, ready for high mechanical loads for a long period of operation.
In the technology of concrete laying in Moscow and Moscow region, used by specialists of the company "SNEP-Stroy" can be identified several important stages.
Laying of concrete floors is made both on concrete plates, and on a ground surface. In both cases, the main work is preceded by an important preparatory stage of leveling the terrain. Compaction of soil, laying sand cushion (0.5 to 1 m), followed by compaction — this is the preparation of the soil base.
Dismantling subjected to destruction and laying new concrete slabs, sealing of cracks, removal of the height differences with the help of milling machines, leveling screed, concrete dust industrial vacuum cleaner is a necessary operation if the concrete placement is carried out on the existing concrete Foundation.
Following the preparatory work, it is time for the waterproofing device in order to protect the structure of the concrete floor from the influence of moisture from the soil or prevent the loss of moisture from the freshly laid concrete mixture. As a waterproofing layer are usually bitumen rolls or plastic film.
concrete floor formwork Installation
Large-scale projects involve the installation of concrete ties on rectangles of a certain area calculated based on the characteristics of the object and the performance of the team. The lines of the perimeter formwork usually coincide with the lines of the expansion joints.
Reinforcement prevents cracks in the concrete, so as reinforcement, depending on the expected load on the concrete floors can act:
a road grid with a cell size of 150?150 mm, or 100?100 mm-classic version;
reinforcement cage made of reinforcement rods with a diameter of 8 to 16 mm — at a high level of mechanical loads. The height of the concrete screed should be at least 12 cm;
metal fiber-to protect concrete from stretching.
The device of the formwork and rebar precedes the main phase of work — the laying of the concrete mixture. Determining the grade and composition of the concrete mix is a professional task, which requires taking into account several important factors: the type of construction, the intensity of the seal, the method of transportation and the method of laying concrete. If it is supposed laying of concrete floors with the strengthened top layer, our experts use concrete of brand not lower than M300 and will organize delivery of concrete mix of the corresponding quality to object in concrete mixers. When the entrance of the machine directly to the place of laying concrete is difficult or impossible, the floor mixture is fed from the concrete pump.
Concrete hardening is a difficult technological process, which is extremely important from the point of view of high-quality, reliable concrete floors. More information about the device of concrete floors with a hardened top layer can be found in the article "Hardening of concrete". Here we restrict ourselves to the components of the complex of measures for strengthening of concrete pavement leveling of the surface, grout, concrete, polymer impregnation, the introduction of the dry hardening mixture, topping, finishing grout the concrete surface, dust removal, coating with special protective varnish.
cutting of the expansion joints
Experts identify three types of expansion joints on the concrete screed, which have their own technological features and serve different purposes:
Insulation seams are laid along the building structures, walls, around the columns just before pouring the floor mixture to avoid the negative impact of deformations from the building structures on the concrete screed.
The expansion joints specify the exact line cracking of the screed during curing, eliminating the possibility of formation of random cracks on concrete surface. Temperature-shrinkage joints are cut at the end of the finishing treatment of the concrete coating, but not later than 72 hours, to a depth of 1/3 of the screed height.
Structural joints perform the function of shrinkage, but they can be judged, where the work of the team was finished laying concrete per shift. Structural seams it is expedient to arrange in places of contact of" cards " of a concrete coupler with different terms of laying.
Filling of seams with the sealing cord and sealing serve as the final stage in the process of laying of concrete floors and is made after time of endurance of concrete. In order for the concrete to gain maximum strength, it takes 28 days, however, if necessary, modern technologies can reduce this period. The choice of the type of sealant is again made on the basis of data on operating conditions, since the seams must be reliably protected not only from contamination, but depending on the nature of the loads — from water penetration, the impact of aggressive media, heavy mechanical loads.