Marine Atmospheric Corrosion of Reference Metals in Tropical Climates of Latin-America

Abstract

This article presents the results obtained at 16 tropical test sites participating in the “Ibero-American Map of Atmospheric Corrosiveness” (MICAT), a project on atmospheric corrosion carried out during the period 1988–1994 at some 70 test sites distributed across 12 countries of the Latin-American region, Spain and Portugal. The tropical climate and its different climatic variants are characterized by high average air temperatures, with considerable daily thermal fluctuations, high average relative humidity, and generally high precipitation volumes. The work is structured in three main blocks: apparently unpolluted atmospheres (i), and marine atmospheres, differentiating between pure marine atmospheres (ii) and those in which both chloride (Cl-) and sulfur dioxide (SO2) pollutants coexist (iii). In each block an attempt was made to determine the role of the tropical climate in the magnitude of corrosion attack shown by four typical reference metals (mild steel, zinc, copper and aluminum) exposed for one-year periods in tropical atmospheric exposure conditions.

Atmospheric Corrosion of Reinforced Concrete Steel in Tropical Coastal Regions

“…Atmospheric corrosivity for metals ranges from C3 to >C5 is according to ISO 9223 standard in tropical coastal atmospheres [1][2]. The influence of atmospheric parameters, chloride deposition rate and other contaminants on metals in tropical climate have been extensively studied; however, in the case of reinforced concrete structure, chloride deposition rate is not directly related to corrosion of the reinforcing steel rebars because the chloride penetration rate into the concrete cover to reach the reinforcing steel rebars surface depends on the concrete properties, particularly it capillarity and porosity [3][4][5][6][7][8][9][10]. The development of the pore structure of hydrating Portland cement systems is fundamental to behavior of concrete exposed to a variety of aggressive environments.…”