Effect of Long-Term Storage of Silicate Brick in Water on its Strength

Abstract

The article is devoted to the study of long-term storage of silicate brick in stationary water conditions on its strength and phase composition. The relevance of these studies is due to the fact that there are a lot of opinions that silicate materials have low water resistance which significantly limits their application range and reduces their popularity among builders. It has been found that after nine years storage in water and followed drying the silicate brick’s strength is practically equal to the initial strength. The data on the phase composition of newgrowths in silicate brick newly made in different production periods and the phase composition of silicate hydrates of bricks water conditioned are presented in the article. Comparison of the X-ray and differential thermal analyzes results of silicate bricks samples after 9 years of water conditioning and samples of newly made silicate bricks showed that highly basic calcium silicate hydrates predominate in a newly made sample, and in a 9-year-old sample silicate hydrates are mainly represented by tobermorite, while the total content of the СSH phase is the same. The content of calcium hydroxide in a newly made sample is higher but this may be due to the completeness of Ca(OH)2 binding in a particular sample but not to its leaching. The fact that leaching of Ca(OH)2 from silicate brick in still water does not occur also can be proved because the water of brick samples storage does not turn pink when phenolphthalein is added. These results allow us to conclude that long-term storage of silicate products in still water does not have any effect on the deterioration of silicate bricks.