Patching Concrete is essential to assess the substrate and decide if the patch will last and hold up. Think of trying to compare it as a metaphor like this. Building a house out of rotten wood. Like wood; concrete can get “rotten.” However, we don’t call it that we refer to it as Concrete degradation. Concrete can become damaged for many reasons: fire, aggregate expansion, freeze-thaw effects, bacterial corrosion like with a carpet on top, calcium break down, physical damage and chemical damage. The Concrete Doctors will help you in your investigation to determine the cause of the deterioration. Addressing the general concrete repair includes testing the site physically with light impact or scraping to decide on how to prevent further degradation. If there is exposed steel reinforcement or large cracks, a structural test will need to be performed. Simply filling holes caused by cracking or left after the loss of spalled or damaged concrete will result in the product failure again.
There are numerous techniques available for the repair; however, each situation is not the same and can be treated as such. Concrete is a structural building material that serves as a walking surface, foundation or barring point in most applications. The specifications for repair techniques used are defined by the situation presented. The proper approach will depend on the cause of the initial damage (e.g. salt, impact, extreme loading, shifting, breakdown of reinforcement, chemical) and if the repair is fully load-bearing merely cosmetic.
Repair techniques that improve concrete strength or performance beyond its original condition include replacement and restoration of concrete after spalling—strengthening to restore structural load-bearing capacity and increases resistance to physical or mechanical attack. Repairs for preventing further ruin include polymer base toppings; increasing resistivity; preserving or restoring passivity; sealers that increase resistance salt and chemical attack; and moisture control.
Techniques for filling holes from spalled or damaged concrete include mortar repairs; concrete repairs troweled or sprayed. The filling of cracks or voids in concrete for structural purposes will involve high strength pinning and epoxy injection. For non-structural repairs where further movement is expected because of environment and heave. Application of low viscosity resins or grouts based on epoxy, or micronised cement