Or you can use a vinyl concrete patching agent and a trowel to fill for a wider crack you will need to use a small mallet. Sikadur Concrete Fix is a two-part epoxy adhesive and filler that can be used as a bonding paste for bridging joints for concrete and most building materials. For cracks smaller than a quarter of an inch, specialists use concrete seals or a liquid-based concrete crack filler. After using the filler to patch the crack, it may be necessary to paint the surface to mask the new filler.
Epoxy injections are also a common method of repairing cracks. Several companies like Slabtec offer structural concrete repair and epoxy-based products that can repair anything from structural cracks to hairline cracks. Pour enough dry concrete mix into a 5-gallon bucket to repair cracks and patch damaged areas. If the area to be repaired is not large or deep, a sand mix or a concrete resurfacer that does not contain gravel can be used.
A standard concrete mix containing gravel works best for patching large or deep areas. In the Australian market, elastomeric masonry crack filler is most commonly applied with a caulking gun to fix narrow cracks in concrete. The quality of the concrete is determined by the particular ratio of sand to the entire collection and water. In addition, if the floor in any part of the building has cracked or has been found to be uneven, an expert should be called in to repair the underlying issues and problems and level the concrete properly.
To repair cracks in a concrete floor, first ensure that the area is free of dust, grease and surface contaminants. It is possible that the subfloor has been compacted and the concrete has been subjected to extreme weight causing it to sink. In other cases, hairline cracks may appear on the surface just after the concrete has been installed. Before resurfacing, blow or sweep away any leaves or debris, then wet the surface to prevent the concrete from drying too quickly.
Once cracks and other damaged spots have been filled, use the trowel to remove excess concrete and smooth the surface. When the carbonation process is prolonged, the concrete can absorb carbon dioxide (CO gas from the atmosphere). Concrete cracked only at the surface, or with hairline cracks where both sides of the crack are still level, can be successfully repaired. There is no doubt that small cracks (hairline cracks) are often repaired with a vinyl patching material used over the crack and levelled with a flexible blade or trowel.
Concrete has a comparatively higher compressive strength, but a significantly lower yield strength. Cracks in concrete can be caused by tree roots and soil movement, as well as by freeze-thaw cycles in winter and expansion during the summer. In the case of hairline cracks, the application of repair putty or crack filler is usually not effective, as the putty tends to flake off the surface over time.