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A series of basic concepts established in the atmospheric corrosion specialty regulations (ISO 9223: 2012, ISO 9225: 2012 and ISO 9266: 2012 Standards) are summarized in this work. In this work, a series of basic concepts established in the atmospheric corrosion specialty regulations (ISO 9223: 2012, ISO 9225: 2012 and ISO 9266: 2012 Standards) are summarized. The concepts are taken into account when carrying out a study of atmospheric corrosion or corrosive aggressiveness of the atmosphere for the metallic materials most used in the construction industry (carbon steel, zinc, copper and aluminum). Some experiences obtained that are not included in the regulations of the specialty are described, derived from the latest studies carried out in the tropical coastal climate of Cuba. This indicates the need to execute whenever possible, the first variant for estimating the corrosive aggressiveness of the atmosphere based on the typical description of the atmospheric environment together with the third variant, based on the determination of the direct measurement of the annual corrosion rate in specimens of standardized dimensions. For certain conditions described, there has been a large difference between the estimation, making use of the indirect annual values of corrosion rate determined by the dose / response functions as the second variant and the third variant for determining the corrosive aggressiveness of the atmosphere for the carbon steel and galvanized steel. [ABSTRACT FROM AUTHOR]

Atmospheric corrosion of carbon steel AISI-1018 was studied in a coastal zone of tropical climate of Cuba with the presence of technologies aimed at the oil extraction and refining in operation. Two outdoor exposure sites were placed in the study zone. Wooden racks with device for determination of aggressiveness agent's monthly and averages annual, a sensor for the measurement of relative humidity-temperature complex, as well as fifteen specimens of carbon steel AISI-1018 for determination of corrosion rate monthly and annual, were installed in each exposure site placed at distance from the sea of 70 and 50 m without shielding effect. Corrosivity category of the atmosphere estimated from the typical characterization of the atmospheric environment and from the indirect values of corrosion ratewas similarity to determine from the annual values of corrosion rate determined directly for carbon steel at the two exposure sites in the study zone. Corrosivity categories of the atmosphere determined was high (C4). The atmospheric corrosion of carbon steel is influenced not only by the wet deposition of sulfate ions, but also by the wet deposition of chloride ions at both exposure sites. The relative humidity-temperature complex had a higher influence on the atmospheric corrosion of carbon steel at the exposure site placed at a higher altitude on sea level in the study area. The effect of height on sea level also influenced in a different classification of the types of atmosphere between the two exposure sites. [ABSTRACT FROM AUTHOR]

Reinforced concrete structures exposed to aggressive coastal environment of Cuba have presented service life term much lower than fifty years. Deterioration problems are mainly due to high intensity of atmospheric corrosion phenomenon in the reinforcement steel embedded in reinforced concrete. Costs in the maintenance and repair works in reinforced concrete structures continue to be very significant. Average annual values of chloride deposition rate transported in the marine aerosol occupy the third place worldwide specifically in zones very near from the sea. However, due to high levels of relative humidity, Cuba occupies a supreme place worldwide in the obtaining of Corrosivity categories of the atmospheres between very high (C5) and extreme (CX) in the coasts north and south. All this justifies the obtaining of innovations based on the technological requirements regarding with the concrete quality increase to build reinforced concrete structures highly resistant to aggressive coastal environment in Cuba. Results obtained are allowing nowadays, for all enterprise and entities in the country in the construction field to carry out the design, construction and investment works with the technological requirements that allow to increase the durability of the reinforced concrete structures with service life term higher of 50 years for all the built heritage and that is built, without additional costs in repair work. [ABSTRACT FROM AUTHOR]

A study about atmospheric corrosión in the Port of Mariel of Cuba was carried out. Research related to atmospheric corrosión in Cuba, have been carried out in the coastal tropical climate without the presence of a large industrial potential as in the study zone selected. Seven exposure sites to different distance from the sea were selected, where for determination and evaluation of chloride and sulphate ions or sulfurs compounds deposition device were placed, as well as probes of different metallic materials more using in the construction industry. A sensor to measure the relative humidity temperature complex in one of the exposure site was placed during the year of study. The results showed that corrosión aggressivity levels estimations from deposition behavior of the aggressive agents and climatic parameter were corresponded with corrosión aggressivity determination from corrosión rate obtained during the year of the study in the four metallic materials tested more use in the construction industry more the galvanized steel. It demonstrated that copper, zinc and aluminum were the metallic materials most affected. The most influential factor in atmospheric corrosión in the five metallic materials was the chloride deposition under a industrial coastal atmosphere, followed by sulfur compounds deposition and the relative humidity temperature complex [ABSTRACT FROM AUTHOR]

An atmospheric corrosion study in the zone of higher generation of wind energy in Cuba was carried out. Five exposure site outdoor to different distances from the sea in the study zone during one year were place. The atmosphere in the study zone was very aggressivity from behavior of climatic parameters and deposition of air pollutants. However, the corrosivity of the atmosphere estimation from corrosion rate values obtained of the dose/response functions was a necessary but not sufficient tool in the study zone for carbon steel, galvanized and copper, confirmed with the visual observation of the metallic probes. It confirms the need to determine the corrosivity of the atmosphere from the direct measurement of the corrosion rate over a one year time. Other factors as adsorption competitive process between chloride and sulphate deposition in the marine aerosol that influenced in the atmospheric corrosion in the carbon and galvanized steel and aluminum in the tropical coastal climate Cuba were showed. The direct influence of the sulphate ions or sulfurs compounds depositions of corrosion atmospheric copper was demonstrated. [ABSTRACT FROM AUTHOR]

The study of the carbon steel atmospheric corrosion at three areas of the coast North western of Cuba was carried out (coast, industrial-coast and industrial) by means of loss weight of steel probe tests, during 24 months. The atmospheric pollutants were also determined as well as the meteorological variables that bigger influence exercice on this type of corrosion. For the evaluation of the morphology of the layers of oxides, a microscope metallographic of reflected light was used coupled to a computer. As main results, the evaluation of atmosphere aggressiveness was obtained, being classified the three study stations as a very high corrosiveness; they were also classified keeping in mind the atmospheric pollutants and the humectation time. It was also analyzed the influence of the pollutants and meteorological parameters on the corrosion speed, obtaining the better adjustment equations for the monthly and trimester tests. From kinetic study of steel corrosion, it was corroborated that it fulfills the bilogarítmic equation C = AtB in the study stations. The constant A value, in the same ones was similar, while the exponent n in the three cases was > 0.5. For this reason the products of corrosion do not present protector properties. The increment of the corrosion speed in the rehearsed metals was adjusted to the exponential equation C = aex/t being proven that the time from which the corrosion begins to spread quickly is bigger in the stations with industrial atmosphere in comparison with the coastal station. According to the evaluation of the oxide layers it was evidenced that in the three research stations, the corrosion products, in a general way, presented a very porous superficial structure, with numerous cracks; they are not also very compact and adherent. [ABSTRACT FROM AUTHOR]