Concrete is the most commonly used construction material in the world with a worldwide consumption of about 12.5 B tonne. It is the most versatile and economical construction material known to humanity. It is used as plain concrete, reinforced concrete and prestressed concrete. In all cases, the failure is initiated by ingress of liquids into concrete. In most cases, the ingress is accelerated by surface cracking induced by shrinkage and creep. In some cases, by stress. The liquids can cause chemical degradation or physical degradation due to freezing and thawing. In plain concrete applications, the failure occurs by surface degradation and spalling. In the case of reinforced concrete, most common failure is due to corrosion of reinforcement. In reinforced concrete, the structural elements are allowed to crack under service loads. The cracking at service loads is not detrimental to these elements as long as there are no intrusions. However, almost all structures are exposed to various types of chemicals and vapors and these foreign elements initiate the degradation. Large amounts of resources are being expended for repair and maintenance concrete structures. Researchers are actively looking for solutions to minimize the problem and identify effective restoration techniques. The results presented in this paper focuses on a coating system that minimizes the liquid intrusion into concrete. This solution is based on the hypothesis that: most if not all degradation of concrete problems can solved if liquids are not allowed to enter the concrete structural elements and at the same time have an outlet for liquids that are already inside. In other words, the surface of the concrete structures should have the least permeability, but should be able to release the vapor pressure created by the water that enters into the system at weak locations. Durability and fracture of concrete and other materials including coatings are also discussed.
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