US EPA

4966906 

Journal Article 

Impact of four kinds of alkanolamines on hydration of steel slag-blended cementitious materials 

Yang Songge; Wang Jianfeng; Cui Suping; Liu Hui; Wang Xueli 

2017 

Yes 

Construction and Building Materials
ISSN: 0950-0618
EISSN: 1879-0526 

131 

655-666 

10.1016/j.conbuildmat.2016.09.060 

WOS:000392770300064 

The impact on hydration of four kinds of alkanolamines (triethanolamine (TEA), triisopropanolamine (TIPA), diethanol-isopropanolamine (DEIPA) and methyldiethanolamine (MDEA)) in a steel slag cementitious system was reviewed. Isothermal calorimetry studies provided information on the hydration heat release rate and the cumulative energy released by blend cement systems. Mortar strength, quantitative X-ray diffractometry, mercury intrusion pore size distribution analysis, scanning electron microscopy and thermogravimetric analysis were used to analyze the mechanism of strength enhancement and microstructure of hydrates that were impacted by alkanolamines. Alkanolamines prolonged the hydrated induction period in the steel slag-cement system, and enhanced the second exothermic peak of hydration at dosages of 0.01%, 0.03% and 0.05%. The second hydration rate was decreased by TEA, DEIPA and MDEA, and increased by TIPA at alkanolamine dosages of 0.1% and 0.2%. The compressive strength and non evaporable water content were enhanced by the four types of alkanolamines (dosage of 0.03%) at 3 d, 7 d and 28 d, which allowed TEA and DEIPA to contribute to strength development and the hydration reaction over TIPA and MDEA. The CH content, porosity and pore size were decreased by alkanolamines at different ages. Alkanolamines promoted the formation of ettringite and an alumina-ferric oxide-monosulfate phase, and the C-S-H morphology was also changed by different kinds of alkanolamines. (C) 2016 Elsevier Ltd. All rights reserved. 

Steel slag blend cementitious material; Alkanolamine; Hydration; Induction period; Microstructure