Open AccessAcid attack on hardened cement paste by acids forming low soluble calcium salts
Author(s) -
V. Pavlı́k
Publication year - 2019
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/549/1/012020
Subject(s) - corrosion , cement , calcium , diffusion , materials science , chemistry , matrix (chemical analysis) , metallurgy , chemical engineering , composite material , physics , engineering , thermodynamics
Solutions of acids have very aggressive effect on the cement matrix in concrete. Aggressiveness of the solutions increases with concentration of an acid but also depends on the acid type. The corrosion effect of solutions of various types of acids and their mixtures on hardened cement pastes is described in the paper. The results confirmed, that the rate of corrosion of hardened cement paste in solutions of strong acids (HCl, HNO 3 ) was faster than in solutions of weak acids. However, the rate of corrosion of hardened cement paste was lower in solutions of acids that produce low soluble calcium salts, because calcium salts filled the pores in the layer of corrosion products and thus increased its diffusion resistance.