Avaliação de pastas de cimento portland cp ii - f com adição de diferentes proporções de peróxido de hidrogênio (H²O²)

Abstract

The present work is related to the addition of hydrogen peroxide in the hydration of masses of Portland cement type CPII - F, in the proportions of 5%, 10% and 15% (m / m). The influence of the same is made through the hydration of the cementitious masses was analyzed through the characterization of the resistance to axial compression and the absorption of water by capillarity. The two main measures are the water sources adsorbed, weakly bound and chemically combined with the gypsum and decomposition products of the aluminates and hydrated silicates of the cement. The third and fourth parts are attributed to the dehydroxylation of 𝐶𝑎(0𝐻)2 and the decarbonation of 𝑐𝑎𝑐𝑜3, respectively, and to the exterior of the reaction of the hydrogen peroxide compound (𝐻2𝑂2). Results related to cement paste aditivated have lower compressive strength, but larger void indices, being themselves the product of hydration of the same. It was also possible to verify that the addition of hydrogen peroxide to the mass curing process gradually increased with the increase in the content, after 28 days of continuous preparation with gradual increases, even with the presence of hydrogen peroxide. Based on the obtained data it was possible to infer that in the proportions used hydrogen peroxide increases the number of voids of the pulp progressively in high concentrations, but if used in smaller quantities can be used as an additive, the advantage being the use in various surfaces in need of a less dense and with more porosity, for example: acoustic coating, thermal coating, among others.