Enhancement and mechanism of hydrated calcium silicate crystal seed on the strength of fly ash-cement mortars
TANG Xiao
LIU Xiaoxuan
SHI Zuoyan
CHEN Xulin
WANG Yong
Abstract：In this study,the effects of hydrated calcium silicate crystal seed(C-S-H seed)on the compressive strength of fly ash-cement mortars and activity index of fly ash were studied.The activiation effect of C-S-H seed on the reactivity of fly ash was studied by measurement of pozzolanic reactivity of fly ash in saturated Ca(OH)2 solution,and its action mechanisms were ana-lyzed.The results show that the C-S-H seed not only effectively improves the early compressive strength of fly ash-cement mor-tars,but also improves its 28 d compressive strength.When the content of calcium silicate hydrate in fly ash-cement mortar reached 1.5％,the ld,7d and 28 d compressive strength of fly ash-cement mortars increased by 69.7％,24.8％and 23.7％,respec-tively.The pozzolanic reaction of fly ash in saturated Ca(OH)2 solution can be significantly promoted by the C-S-H seed.At 7 d of reaction,the content of Ca(OH)2 decreased by 5.35 percent point,the content of chemically bound water increased by 1.05 per-cent point,and the surface of fly ash particles was obviously dissolved and covered with large amount of reaction products.
Keywords：C-S-H seedfly ash-cement mortarcement hydrationpozzolanic reaction activationcompressive strength
Publication Date：2024-10-25
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：5( 37-41 )