Title: A Study on the Effect of Some Ions Contained in Seawater on Hydrated Cement Compounds

Author(s): C. P. Ftikos and G. Parissakis

Publication: Symposium Paper

Volume: 100

Issue:

Appears on pages(s): 1651-1666

Keywords: cement pastes; chlorides; compressive strength; C3A; C-S-H; electron microscopes; hydration; portland cements; sea water; portland pozzolan cements; Santorin earth; sulfate attack; X-ray diffraction; Materials Research

DOI: 10.14359/2208

Date: 4/1/1987

Abstract:
The present paper concerns the study on the action of SO42-, Cl-, and Mg2+ ions, which are contained in seawater, and the influence of them on hydrated cement compounds, of pure cements of different C3A content and cement pozzolan pastes, by x-ray diffraction and scanning electron microscopy. Compressive strength development has also been measured. The study shows that these ions affect the compressive strength development after six months, independently of C3A content, in pure cements. It is also shown that the presence of chlorides promotes the formation of chloroaluminates, and more penetration of Mg2+ ions, which leads to the formation of porous C-S-H compounds. Cements with a good interground pozzolan are more resistant to this attack.