Abstract

Carbonation of concrete is the second reason of corrosion on reinforced concrete structures. This has led to study the methods that might be useful for defining, from the phase of project, the conditions that a certain concrete must have, besides resisting mechanically, to be resistant to external attacks like it is the effect of the CO 2 of industrial environments. With the purpose of establishing a simple method of testing that complements the compressive strength, and that allows to predict the useful life of the concrete in terms of its carbonation, possible relations were studied between four parameters: depth of carbonation, capillary absorption, porosity and compressive strength. Samples were made by concretes with w/c 0.45-0.53-0.59. The three concretes were prepared under the same procedures and with the same cement, sand, gravel and additives. The samples were tested to compressive strength, capillary absorption and porosity, at different times of accelerated carbonation in a chamber designed for such purpose. The results showed a direct relation between coefficient of capillary absorption and depth of accelerated carbonation on a concrete. The tests of porosity did not show any correlation with the depths of carbonation and with the coefficient of absorption either. Finally it was found that the coefficient of absorption can be used as tool for the development of a new method of quality control for concrete durability.