Análise da durabilidade do concreto com ar incorporado para uso em paredes estruturais

Abstract

The objective of this work is to present a study of durability of concrete walls, using air entraining admixture, under weather actions, on systems commonly used to house’s construction. To achieve this goal, several specific characteristics will be evaluated by the variation of the entrapped air content in the concrete. Service life prediction will be considered through accelerated tests such as the accelerated carbonation test and acid attack. Furthermore, evaluation tests of performance in structures such as testing permeability, made in vertical sealing systems will be done. In addition, compressive strength and water absorption by capillarity will also be checked for the test specimens. For tests performed in the vertical sealing will be used prototypes made in similar dimensions, which reproduce the real conditions of this system. Concretes with 0,0%, 0,5% and 1,0% air entraining admixture contends were evaluated and the 0,5% contend has showed the deepest carbonation and greater weight loss due to acid attack. For the 1,0% contend the results showed a tendency of decreasing pore connection compared to the 0,5% contend, as it obtained a greater resistance to the acid attack and the carbonation, even with a great variability. The results of capillary absorption converged to the same average results according to the type of cure. Thus, in this study the durability of the structure was not affected by the increase of air entrained contend.