Influência da carbonatação no ensaio de esclerometria

Abstract

Carbonation is a physicochemical process where there is a neutralization of the solution present in the concrete pores. In the carbonation process, occurs th e reaction of alkaline ions present in cement with gases present in the atmosphere. Due to the reduction of the concrete alkalinity, the reaction results in the degradation of the passivating layer that surrounds the reinforcement, which may cause the corr osion formation process to begin. This work aims to characterize the influence of carbonation on the sclerometer test by characterizing the sclerometric index, the compressive strength and the analysis of the influence of carbonation on the sclerometer tes t performed on the produced specimens. In this work, an experimental program was carried out, in which twelve specimens were produced and divided into four groups of three samples. Each group was exposed to CO2 for different periods, which were respectivel y 0, 15, 30 and 120 minutes. The concrete was produced with CP V ARI cement and did not undergo a curing process, and the CO2 exposure process was performed after the specimens were deformed. The results indicate that as carbonation increases, the sclero metric index and the compressive strength decrease. However, the proportion of the increase in carbonation and the reduction in the sclerometric in dex and compressive strength are highest in the first thirty minutes of exposure to CO2. For the sclerometric index, 55.9% of the total reduction occurred in the first thirty minutes. While for compressive strength, 83.8% of the total reduction occurred in this same period. Among the conclusions presented in this paper, it is important to emphasise that the highe st reduction rate of the sclerometric index and the compressive strength occurred during the period of greatest CO2 diffusion.