Nâng cao tuổi thọ công trình bê tông cốt thép

Abstract

Research on corrosion and anti-corrosion for concrete, reinforced concrete to enhance durability and prolong the life span of structures is a matter of concern to many scientists and agencies throughout the country. The raise of quality and life time of buildings is also considered to improve the corrosion resistance for concrete and steel in reinforced concrete structures. Many studies have reached a unified conclusion about the cause of corrosion is due to the hydration products of cement dissolved in the environment or interact with salts, acids in environment to create compounds with properties of strong melting or volume expansion causes destruction of the internal structure of concrete. In our country the issue of corrosion and corrosion protection of concrete and reinforced concrete structures has only focused on constructions in the marine and coastal environment but has not paid much attention to the corrosion protection issues for concrete and reinforced concrete constructions in other environments. Along with the concrete erosion by environmental agents, there is also a corrosion of reinforcement in concrete environment. That is an oxidation process, followed by the breakdown of passive protection layer of reinforcement due to penetration of chlorur ion or carbon dioxide. At the iniation this corrosion does not happen on the surface of steel, but only propagates when a threshold limit value is reached. Within the scope of this article, basic mechanisms of these types of corrosion will be displayed and solutions to improve the service life of reinforced concrete structures according to EN 1054 will be applied.