Grouting concrete with rotary machines
Concrete surfaces after their manufacture need additional protection. Therefore, special additives have been developed that are applied directly to the material that has just been poured. After this, the concrete is ground by a helicopter - with one or two-rotor machine.
General information
Currently, this method is considered the most advanced and inexpensive to process concrete surfaces.
The result is a smooth, durable and dust-free floor that gets:
- moderate oil and petrol resistance;
- different colors.
The big positive moment of the grinding technology with troweling machines is getting the finished coating simultaneously with the laying of the concrete mix. This makes it possible to accelerate the completion of the construction of the object and save on finishing coatings. On the scale of large areas, the price of the effect can be more than one million rubles.
| Application | Experienced builders try to apply this technology wherever possible. The process of grouting and grinding a concrete surface with a hardener can be considered universal. For warehouses, production premises (workshops) and parking lots, the method is ideal. |
| Not applicable | In especially clean laboratory rooms, in areas with an aggressive environment and where special requirements are imposed on the color of the coating. It is not recommended to make floors of concrete with grouting and grinding in household and residential premises, because they are “cold”. |
Remember that technology can only be applied on wet concrete. Therefore, in advance, take care of the preparation process, you can also find a specialized organization engaged in laying concrete floors, or purchase equipment and try to do the troweling with your own hands.
The main difficulty of the process is grouting and grinding, since it is difficult to predict how concrete will behave. Therefore, it is important to feel what to do, and this comes with experience.
Using disc-blade machines
The technology of concrete grouting by helicopter consists of two stages:
- Grind the concrete surface.
- Apply dedusting strengthening impregnation.
Grouting is necessary in order that the concrete "milk", which protrudes on the surface of the concrete mix after its treatment by vibro-mechanical method, did not flake off when operating the floor. In this case, disk-blade trowels or "helicopters" are used. In the process, they compact the concrete surface and bring it to a mirror shine.
Tip: always place when grouting concrete spare equipment in case the main fails.
If the surface is subject to high requirements for abrasion and strength, topping, topping is used - a dry reinforcing mixture, which is based on cement. Also added to the composition of quartz or other components with enhanced abrasion resistance and hardness.
At the first stage, a special topping, for example, “Refloor RF” must be rubbed into the newly laid and leveled concrete. On the second - additionally dedust with impregnation, which will help stabilize the surface and reduce the formation of cracks to a minimum value. It also binds at a chemical level the salts located in the concrete structure and causing the formation of dust, as a result of which the surface becomes dustless.
Tip: Often you can’t independently dismantle concrete rails or structures, in this case reinforced concrete cutting is used with diamond circles.
Roughing grout
Before starting the grouting of concrete, it is recommended to take a technological break. This will allow the material to gain initial strength. Break time depends on the temperature and humidity of the environment and can be 4-20 hours.
Usually, this is enough for the concrete to set in such a way that, when stepping on its surface, there will be a trace of a depth of 2–3 mm. Now you can begin a rough grouting of the surface of the newly laid material.
You can make it a disk or trowels with floating blades for 2 passes. The direction of movement in this case on the second pass should be perpendicular to the direction of movement during the first.
Tip: first of all treat concrete surfaces that are located next to columns, pits, doorways and walls, because this is where the mixture hardens first.
In this case, grouting can also be done with the help of edge smoothing machines, which are equipped with a freely rotating wheel.
When using topping, it is carefully sprinkled over the surface, ensuring uniform layer thickness. This can be done by hand or use a special trolley for wastage.
Its construction is as follows:
- load topping available container;
- grinding the mixture in the container - auger;
- adjusting the level of wastage - metering valve;
- that there are no deep tracks on the surface - wide wheels.
Tip: there is a need to manufacture a through channel in concrete? Diamond drilling of holes in concrete with necessary crowns for diameter will help you.
Instructions for making topping:
- Add in the first stage 2/3 of the total consumption per 1 sq. Km. m;
- Make a coarse grouting with a concrete shuttering machine. Carry out the process until the topping absorbs moisture from the concrete mix, which will become noticeable by darkening of the surface.
- Immediately after this, add the remaining 1/3 parts so that he has time to soak in the moisture from the cement “milk” before the water evaporates.
- Proceed to the second coarse grout, as soon as the mixture is saturated with moisture, according to the principle described above.
Tip: instead of purchasing the equipment in the property, you can rent trowels on concrete for rent.
Most often the floor with topping can be observed:
- in warehouses where heavy loading and unloading equipment is used;
- in production workshops;
- in the markets;
- in shopping centers;
- parking;
- on other objects where there is an increased pedestrian and traffic load.
Grout Finishing
In the process of rough grouting, the concrete gradually increases its strength. Take into account that the moment when it is necessary to carry out a final grout is determined visually and only a specialist can do it.
Tip: one of the signs is that the surface of the concrete floor looks pretty smooth after the grouting, but the blades of the mechanism do not collect cement “milk” from it.
The process is carried out using finishing blades trowels for at least 2 passes. It is best to use equipment that has intersecting blades, which greatly simplifies the process.
On each approach it is necessary to make two passes, while the direction of movement in the second case should be perpendicular to the first. Usually, with the first approach, there should be a distance of 5–10 mm between the edge of the blades and the level of the floor, and 20–25 mm with the second approach.
So it is possible to bring the surface of the floor to a mirror shine. Grind until the material attains such a level of strength, when no traces remain on it.
Tip: on a large area it is better to use a double rotor industrial machines.
Conclusion
Grinding of concrete allows to achieve surface hardening, add and improve its characteristics. Work should be carried out only on raw material until the desired results are shown. It is best to use special rotor mechanisms for this. The video in this article will help you find additional information on this topic.