TWO TYPES OF C(A)SH IN THE HARDENED CEMENT PASTES USING LOW HEAT / ORDINARY PORTLAND CEMENT EVALUATED BY NITROGEN SORPTION

摘要

In this study, we revaluated the Tennis and Jennings’ model of two types of calcium silicate hydrates in Portland cement based on nitrogen sorption measurement on low heat / ordinary Portland cement with W/C ratio = 0.55. Optimized results indicate that the ratio of low-density C(A)SH to total amount of C(A)SH increases with progression of the hydration in the case of ordinary Portland cement. Whereas this ratio for low heat Portland cement paste increases until degree of hydration of cement gets around 0.6～0.7, then decreases at higher degree of hydration.