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The Purpose of Concrete Coating

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Coating of concrete performed by applying liquid or semi-solid materials to a concrete surface. The concrete coating can be paints, cement-based topping, overlay, and epoxy aggregate system. The purpose of the concrete coating is to stop the ingress of water inside concrete. The prevention of water ingress will prevent the ingress of aggressive chemicals such as chloride and sulfate. Chloride diffuses into concrete in solution. The ingress of chloride will adversely affect concrete durability. Chloride will cause steel corrosion. Corroded steel will expand and exert stresses on concrete which can cause concrete cracking and spalling. Also, the effective cross-section and tensile strength of steel will be reduced. The ingress of sulfate will affect concrete durability also. Sulfate will react with concrete causing destructive expansion. 
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The concrete coating should prevent the ingress of water. If the water gets behind the coating under unknown conditions. The water will be trapped between the coating and concrete surface. The vapour pressure of trapped water will reduce the adhesion of the coats to concrete surface, and the coating will start to peel off. Moreover, the water will create a suitable environment for the growth of mould (fungal hyphae) on a concrete surface. 

The selected surface treatment should be impermeable to liquid water but permeable to water vapor. The discharging of water vapor is important to avoid the undesirable effects such as loss of coating adhesion and growth of mould on the concrete surface.  





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My name is Mohammad Hamdan, and I am a Civil/bridge Engineer with extensive professional background and experience in the field of construction. I have 10+ years of experience in the construction field. During my professional career, my emphasis has been placed on structural projects, mainly bridges, infrastructure and roads. Reading and practicing the design of structures is my passion.i was lucky to be a part of a big team that executed major highway interchanges. I believe in spreading the knowledge, thus, i compose these courses to share my experience and knowledge. My course focuses on the practical side of construction field. On other word, i am sharing some of what new engineers need to know about construction field. Beside working on construction field, i love writing some articles on my website ( curious civil engineer) Moreover, i wrote some engineering papers, you can check them  by searching my name on Google (Mohammad mamon Hamdan)