Concrete rehabilitation and restoration is a general name for well-defined and approved engineering design for the rehabilitation and treatment of concrete elements and infrastructure damaged by rebar corrosion.
In these cases, corrosion is formed and erosion of rebars can progress to the point of collapse or increased disintegration of the concrete elements. This erosion weakens the concrete element, sometimes to the point requiring structural treatment.
Corrosion in buildings and concrete is manifest in all economic sectors, being the primary cause of damage to the lifecycle of buildings and structures throughout the world. Studies by NACE, the international corrosion organization, estimate corrosion damages in the United States in 2016 at 1.1 trillion dollars.
The phenomenon of corrosion is present in most concrete buildings, albeit at various stages of development. Corrosion accelerating factors, leading to concrete disintegration, are inherent to various environmental conditions, such as: Marine environment saturated with sea-borne chlorides, chemical environment with particles that penetrate concrete, exhaust gases in urban environments causing carbonation of concrete.
Our Company offers a basic treatment procedure for rehabilitation and restoration of concrete element that is based on years of engineering knowledge and experience. However, each project is a case onto itself, requiring specific design and implementation of a rehabilitation system that is adapted to its environment, in accordance with Standard EN1504 and/or other standards. In most projects, close support by a certified structural engineer is provided for monitoring the rehabilitation process.
Basic Procedure of Concrete Rehabilitation
- Excavation or chipping for the removal of loose plaster and concrete until a stable base is obtained.
- Fully exposing the rebars longitudinally and laterally.
- Cleaning the rebars and removing loose scales and corroded parts to obtain clean metal that conforms to the standard.
- If necessary and according to the structural engineer’s instructions, rebars that lost diameter thickness must be replaced. This is done using various techniques as required by the project.
Applying a concrete rehabilitation system:
- Application of an inhibitor layer by impregnation. The purpose of the inhibitor layer is to prevent the formation of future corrosion in existing concrete surfaces and extending the life of the existing structure.
- Washing and clearing the exposed area with pressurized freshwater to remove salts and other contaminating particles.
- Application of anti-corrosive primer on the rebars and on concrete areas that were stripped and are to be patched.
- Placing designated polymer-enriched concrete for the repair and filling of cavities until the original dimensions of the concrete element is obtained. Filler mixture will be thixotropic or grout, as required. Application is manual or by mechanical spraying of filling materials.
- After the technical-constructive process of concrete restoration is completed, a technical-decorative process is implemented. This includes an application of a variety of plaster systems, coatings (paint), dry or wet cladding, according to the requirement of the client or designer.