The design before the construction of epoxy flooring and the organization of professional construction team control the whole process of checking and handling the correct construction organization and quality supervision. Before the construction of epoxy floor paint, it is necessary to clearly understand and check the condition of the base layer. The following describes the requirements and common treatment methods for the ground base layer of the general epoxy floor industrial floor paint coating.
1) Cement base surface is firm, firm and can not afford shelling. Mortar shelling should be eliminated. Concrete layer and mortar leveling layer should be poured together. If the concrete layer is poured first, the thickness of the mortar layer is not less than 40MM, and the thickness of the forklift lane is thicker. The slope should meet the design requirements, and the allowable deviation is 2% and not more than 30MM.
(2) No sand on the surface, high hardness and no cement powdering are required. The newly poured cement mortar should be fully maintained. The cement base surface is flat, without rugged, honeycomb linen, cement bumps, other coatings, latex paint, foam sugar and other residues. (3) The surface is dry, the moisture content is less than 6%, no oil pollution, and the PH value should be 6.0-8.0. After the maintenance period of cement ground, the base can no longer be washed or wetted with water 5 D before construction.
2. The inspection and pretreatment of the base is the basis of epoxy floor coatings. Detailed inspection and analysis are needed to determine the treatment measures.
(1) Measure the compressive strength. The compressive strength of industrial floors should not be less than 24 MPa. In order to meet some important requirements, higher strength may be needed. Strength measurement should be carried out by rebound meter or coring.
(2) Determine the bond strength. The low strength layer formed by cement slurry is usually in the thickness of several millimeters on the surface of concrete base. The stress caused by shrinkage, temperature change or repeated action of load caused by hydration reaction of cement will lead to the decrease of bond strength. The bond strength should not be less than 1.5 MPa.
(3) Water content of grass-roots. Only when the moisture content of cement base is not more than 6%, can the coating be applied, so the measurement of moisture content is particularly important. The best method to determine the moisture content of the base course is the plastic film covering experiment method, that is, at least 1mX1m polyethylene film is sealed on the concrete surface with tape, and after at least 24 hours, the moisture content is determined according to the amount of condensation water appearing on the plastic film.
(4) Environmental temperature. Ignoring the temperature factors of construction environment can lead to quality defects of epoxy floor, such as reduced bond strength, watermarking, voids, irregular surface and hardening. Therefore, the environmental temperature (air temperature), the surface temperature of the grass-roots, dew point temperature and other data, in the construction must be measured several times a day.
(5) grass-roots clean-up. For oil, oil or organic acid, inorganic acid or cement slurry pollution, if not thoroughly removed, will affect the bonding performance of epoxy floor paint coating. Therefore, the surface must be cleaned mechanically and checked by measuring the bond strength.
3. Grass-roots treatment
(1) In order to achieve good results in the construction of epoxy floor coating, cement leveling layer should be first applied to leveling the ground that has not yet been leveled. When the cement is initially solidified, the civil engineer uses professional ground machinery to grind the ground. The surface of epoxy-coated floor will be smoother, brighter and the service life will be improved after basic treatment and re-coating.
(2) After the cement layer is dried (about 28 days), the whole ground is polished with a grinder to make the surface smooth and the cement capillary holes open.
(3) For the base layer with oil contamination (edible oil, engine oil), the surface treatment agent is sprayed on the surface wetted with water and scrubbed repeatedly until there is no oil contamination.