Concrete coating systems

Steel, whether in structural form or as a sheet, can be protected by many different coating systems, such as paint, plastic materials, concrete and other metals, either singly or in combination (such as a metal coating followed by a paint system, or a plastic coating). Examples of this compound type of... 

Surface preparation depends on coating formulation and intended usage. This could vary on steel substrates from a commercial to a white metal blast. Profile is also essential to obtain ultimate adhesion. The depth of profile required is proportional to the total dry film thickness of the coating system. On concrete surfaces, the general requirement is to remove latents and contaminants and this can be accomplished by chemical preparation, scarifying or abrasive blasting. 

UV-curable concrete floor coatings provide a durable, high-performance, and eco-friendly solution. These thin-film coating systems cure instantly, thereby minimizing the downtime of any facility. Other benefits of these coatings include excellent chemical resistance, little odor, the ability to coat in cold conditions, and ease of cleanup [33],... 

Organic coatings are used to block the penetration of carbon dioxide or chloride ions. They form a continuous polymeric film on the surface of the concrete, of a thickness ranging from 100 to 300 pm. The binder can already be present in the liquid paint as a polymer, or the polymer can be formed due to chemical reactions between monomeric components that are mixed just before application. Modem coating systems are usually built up of several layers applied consecutively. They are compatible with the alkalinity of the concrete and are based on various types of polymers (e. g. acrylate, polyurethane, epoxy), pigments and additives, and are made suitable for application by the addition of solvents or diluents. 

Polymeric anodes are used to mitigate the corrosion of reinforcing steel in salt-contaminated concrete. The system consists of a mesh type of anodes with a conductive polymer film coating on copper conductors. 

Architectural paints are applied in situ with brushes or rollers in Europe, but spray application is widely used in the USA on concrete and wooden buildings. Paints on windows and doors are brush applied. Structural components (e.g., doors, windows, radiators) that receive primers or complete coating systems during production or in the workshop are dipped or sprayed. 

Floating platforms are generally protected by CP (sacrificial anodes or impressed current) combined with a high-quality paint system. Pipelines with an organic coating and an external concrete coating are also protected by sacrificial anodes. 

BS EN 1062-3 (1997). Paints and Varnishes - Coating Materials and Coating Systems for Exterior Masonry and Concrete. Part 3 Capillary Absorption and Permeability to water, British Standards Institute, London. 

Chem. Descrip. Waterborne aliphatic urethane polymer emulsion Uses Urethane for metal primers, topcoats, floor coatings, etc. binder for pigmented and clear coat systems for wood, metal, concrete, other substrates... 

Uses Acrylic for hydraulically setting systems, syn. resin plasters, concrete coatings, emulsion paints... 

The common coating systems for concrete are listed in Table 14.19.1.2. Synflietic resins (e.g., chlorinated rubber, styrene resins, acrylic resins) contain normally 40-60% solvents and form a thin film. Several coats must be applied. Reactive resins may require little or no solvent. 

Table 14.19.1.2. Survey of often used coating systems for concrete...

Regardless of which coating system is selected, surface preparation is important. An abrasive blast, even on concrete, is required. In addition, all surface contaminents must be removed. When coating concrete a thicker film is required. System F in Table 14.2 is recommended for optimum protection. 

RP0591-91 Coating for Concrete Surfaces in Non-immersion and Atmospheric Service—Item 21052-P RP0692-92 Application of a Coating System to Exterior Surfaces of Steel Rail Cars—Item 21058-P TM0170-70 Visual Standard for Surfaces of New Steel Air-blast Cleaned with Sand—Item 21201-P TMO175-75 Visual Standard for Surfaces of New Steel... 

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