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Mechanisms of Degradation of Portland Cement-Based Systems by Sulfate Attack.


pdf icon Mechanisms of Degradation of Portland Cement-Based Systems by Sulfate Attack. (644 K)
Ferraris, C. F.; Clifton, J. R.; Stutzman, P. E.; Garboczi, E. J.

Chapter 22;

Mechanisms of Chemical Degradation of Cement-Based Systems. Proceedings of the Materials Research Society's Symposium on Mechanisms of Chemical Degradation of Cement-Based Systems. November 27-30, 1995, Boston, MA, E & FN Spon, London, England, Scrivener, K. L.; Young, J. F., Editor(s)(s), 185-192 pp, 1997.

Keywords:

portland cement; degradation; sulfate attack; microstructure; mortar; environment influence

Abstract:

Although the chemical mechanisms of sulfate attack have been studied by many researchers, considerable disagreement exists over the mechanics of the associated expansion and cracking processes. Studies were carried out by exposing mortar and concrete specimens of different geometries (prisms, cylinders, and spheres) to sodium sulfate solutions with controlled pH. Relationshios between the formation of reaction products and the expansion of portland cement mortars were investigated by idenfigying the reaction products present as a function of attack depth and amount of expansion. Simulation modeling based on a finite element approach is being performed to elucidate the mechanics of cracking induced by sulfate attack.