When the floor is being painted in Chongqing, the expansion joint is filled with a rigid resin mortar material epoxy (a solvent-free product) and then treated in accordance with the general coating. From the floor, no cracks are observed in the floor covering before cracks occur. Seam. This method does not guarantee that the floor covering on or near the expansion joint will not crack or scribe. Because this steel is not elastic, it cannot withstand the cracking stress caused by the shrinkage of concrete, so cracking cannot be avoided.
If the owner allows a flat and uniform expansion joint on the floor, after painting the floor, the cutter can cut the expansion joint 2-5 mm wide at the original position of the expansion joint, so that the concrete has an expanding and shrinking space. Uneven cracks appear, reducing roof lining along cracks.
For epoxy floor coatings, the expansion joint is filled and filled with an elastic material (such as polyurethane elastic rubber), and then an intermediate coating and a top coating are applied. The specific operation method is as follows: First, check each expansion joint, clean the expansion joint with a width of 5mm or more, and then fill and smooth the elastic glue. For expansion joints with a width of less than 5 mm, because the seams are too thin to fill, first cut the shape of the ladder to a width and depth (depth better than 1 mm), and make sure that the cut is clean, and then you can pour elastic rubber.
Elastic rubber filling method: According to the product description, the manufacturer of the elastic rubber or the filled glass gun (glue gun) should pay attention to avoid contaminating the rubber outside. If stained, remove it immediately. After filling the space, use a blade to flatten and remove excess glue. The elastic rubber filler has a certain depth to remove dust and other impurities in the space before filling; otherwise, the elastic rubber and concrete may not be able to be firmly attached and disassembled.
Compared to one method, this treatment method is characterized in that the elastic rubber disperses the tension caused by the shrinkage of the concrete and significantly reduces the possibility of cracking of the coating in the expansion joint and the color of the entire surface. It is uniform, but the elastic rubber coating is still rigid. When the concrete shrinks more severely, the floor covering (the intermediate coating and the top layer) on the elastic rubber will still crack, but the cracks will not be very large.