When signs of cracks are found on a concrete, the condition of the concrete is first evaluated by a professional repairer to determine if the damage is structural or superficial and if it is a structural crack, it should be likely a large diagonal crack running across a concrete beam, which is a delicate and critical job that can be repaired by an engineer. During the evaluation procedure, a hammer is used by pinging the concrete surface to determine if there are delaminated areas, which produces a dull, hollow sound, and when there are delaminated areas, these are outlined by a spray paint. When the concrete damages have been evaluated, the extent of the damage is measured and documented by taking notes on the evaluation, as well as taking photos of them.
It is important to determine the problem and cause of the concrete damage so the right repair method can be applied, so these are the common problems and their causes: corrosion of reinforcing steel, which is caused by the presence of chloride ions in the concrete that react with the steel that eventually results to rusting; freeze-thaw disintegration, which results when the concrete is porous such that water seeps in and freezes and breaks the concrete surfaces; alkali-aggregate reaction, which is a result of reactive aggregate in the concrete that forms a gel around the aggregate particle, such that when the gel gets wet it expands the aggregate and the expansion destroys the concrete; drying shrinkage cracks, which is a condition when the concrete has more moisture content, such that when water evaporates there is tendency for the concrete to shrink; plastic shrinkage cracks, which is a condition when the concrete surface dries out first before the concrete can gain strength, a pattern of cracks will form on the surface; blisters or delamination, which is a condition which results into bubbled concrete surfaces caused by premature finishing and sealing of the concrete surface, which seals in air and bleed water; and cracks from structural loads. Know more about Miami Concrete Restoration.
If the result of the evaluation and determining the problem points out to a surface repair, the next step is to find out the type of repair to be done, such as: full-depth repair, which is cutting out the damaged concrete, replacing the reinforced steel and replacing the concrete; partial depth repair, which is cutting around the edges of the damaged area, removing the damaged concrete, cleaning or replacing the reinforced steel, then placing a repair mortar; and overlays, which is an effective procedure to cover up a surface problem for as long as the surface preparation is used.
For simple cracks at home, an easier method to permanently repair the cracks is by using low-pressure injection of an epoxy or polyurethane foam material and this method can also be used for the repair of concrete floor cracks. Check out Miami Terazzo Restoration for more info.