Study of changes in concrete durability during the operation of buildings

Abstract

Abstract The purpose of this study is to select the best methodologies for determining the condition of concrete structures. Semi-destructive concrete exposure methods were used to determine resistance parameters: the impact echo test to determine internal structure, the Figg test for air permeability, the initial surface adsorption test for water adsorption, titrimetric for chloride amounts, and a chemical and physical method to determine carbonation levels. In addition, two situations were simulated: a fire and a pipe burst and their impact on the condition of reinforced concrete structures. It was shown that the exposure to temperatures decreases the level of acidity, resulting in increased corrosion of steel. During a pipe burst, the amount of chlo-rides increases, which affects the reinforcement, oxidizing it. A search for possible correlation between concrete structure and carbonation, air permeability and water adsorption was also carried out. It was found that there is an almost linear dependence of these parameters on the presence of cracks, the deterioration of the structure leads to an increase in the transport properties of concrete, which becomes a danger to steel.