How to install self-leveling compound successfully?

Ground base treatment is an important prerequisite for ensuring the quality of cement self-leveling construction. Whether the surface self-leveling cement can be firmly bonded to the base surface without peeling is closely related to this.

 

1. Ground base treatment

 

Ground base treatment is an important prerequisite for ensuring the quality of cement self-leveling construction. Whether the surface self-leveling cement can be firmly bonded to the base surface without peeling is closely related to this. Therefore, this link must be taken seriously by construction personnel.

(1) Check the ground. First check the original cement floor. It is required to be free of hollowing and sand. The concrete floor strength is generally required to be above C25, and the ground moisture content is less than 8%. The new concrete floor requires a maintenance period of more than 20 days; (2) If there are many and concentrated cracks in the substrate, treat the cracks to avoid defects caused by cracks. After solidification, the next process can be carried out.

(2) Ground rough grinding. Use a grinder to rough grind the ground to remove grease and loose parts. Repair cracks, holes and relatively large height differences and then clean the ground

2. Apply interface agent

 

(1) Apply interface agent. According to the ground conditions, the first coat is to mix the high-efficiency interface agent with water in a proportion (emulsion: water = 1:1-2), and then apply it to the surface with a roller or sprayer. Wait for 3-4 hours, and then apply the second coat. The method is to mix the multifunctional interface agent with water in a proportion (emulsion: water = 1:1-2) or pour the original liquid on the ground. Then sweep it with a broom. Generally, it is applied twice. However, for the part with greater water absorption, it is necessary to apply it several times until the ground is completely sealed;

(2) Wait for the interface agent to dry on the surface. According to the temperature and ventilation conditions of the construction site, the cement self-leveling construction can be carried out when the interface agent is dry on the surface and there is no accumulation of liquid, which usually takes 4-5 hours.

 

3. Mixing

 

Whether the mixing of cement self-leveling is correct directly affects the fluidity, strength and surface color uniformity of self-leveling cement.

(1) The amount of water should be correct. The amount of water added to the self-leveling cement for the surface layer is set to add water (5.3~5.7 kg) per bag, and the water consumption is usually 5.5 kg/bag. During construction, water must be weighed with an electronic scale, otherwise the color difference of the self-leveling cement will be too large after construction;

(2) Stirring should be sufficient. Use a stirrer or double-head mixer with a larger power and a faster speed (generally 750 rpm) for stirring. The stirring time must reach about 3 minutes of continuous stirring to allow the additives in the self-leveling cement to fully dissolve and take effect. This will make the slurry more uniform and more fluid.

 

4. Surface layer cement self-leveling paving

 

(1) Paving process

Pour the stirred surface layer cement self-leveling slurry along a straight line onto the treated base surface according to the construction direction determined at the construction site. Use a special toothed scraper to assist flow and control the construction thickness. Then use a defoaming cylinder to roll in the slurry to remove bubbles in the slurry. For the joint of the two barrels of slurry, roll several times to eliminate the height difference of the interface;

(2) Precautions

① For surface layer cement self-leveling, the construction thickness is more than 5mm, and 12mm is best. This makes it easy to get the ideal flatness and uniformity;

② Note that in the construction of the surface cement self-leveling, the time required for each bag of material from mixing to defoaming should not exceed 15 minutes. The site should be closed immediately after the construction is completed. No walking for 6 hours. Avoid heavy objects within 20 hours. Walking is allowed 24 hours a day;

③ The amount of self-leveling cement is generally 2kg/mm/㎡.

5. Apply surface care agent

About 48 hours after the cement self-leveling construction is completed, apply a water-based transparent topcoat on its surface and it can be opened for use. Notes:

If you want to finally get the perfect self-leveling cement surface effect, you need to pay attention to the following points:

1. If the cracks in the base ground are not treated, the self-leveling cement surface will crack;

2. Insufficient strength of the base ground will cause the self-leveling cement surface to delaminate, hollow, and crack;

3. Improper selection of interface agent or incorrect use method will cause many volcanic holes in the self-leveling cement surface;

4. Water absorption on the ground causes the fluidity to lose too quickly, resulting in roller marks and joints;

5. Unqualified mixer, unweighed water addition, and insufficient mixing time will cause color difference and undispersed raw material particles on the surface;

6. Spraying the topcoat material too early or applying the topcoat material in an improper way will cause spots on the surface.