Hydration characteristics of magnesia-phosphate cements at low temperature

Author(s): H. H. Yi, K. Liu, D. X. Li
Paper category: Proceedings
Book title: Proceedings of the Seventh International Conference on Concrete under Severe Conditions – Environment and Loading
Editor(s): Z.J. Li, W. Sun, C.W. Miao, K.Sakai, O.E. Gjørv, N.Banthia
ISBN: 978-2-35158-124-7
e-ISBN: 978-2-35158-134-6
Publisher: RILEM Publications SARL
Publication year: 2013
Pages: 937-945
Total Pages: 9
Language : English

Abstract: This paper has been conducted to investigate the hydration characteristics of magnesia-phosphate cements (MPC) at low temperature (~0℃). The cement were prepared by mixing dead-burned magnesia (M), and mono-potassium phosphate (mPP), with/without fly ash; in addition, borax (B) and di-potassium phosphate (dPP) were used as the retarders. The MPC materials were curd at low temperature (~0℃), and the setting time, compressive strength, and the linear expansion rate were measured. The hydration behaviors were compared with that of MPC materials curing at a ambient temperature of ~20℃. The results indicate that, through incorporating fly ash, the compressive strength and properties for low temperatures of MPC materials could be improved significantly, the setting reaction of MPC are slowed down in low temperature, however, the long-term mechanical strength are not affected dramatically; The XRD patterns indicate, MgKPO4·6H2O are the main hydrate in MPC materials, and morphology analysis was taken by SEM, in 28d specimen, dense microstructure with deep hydration degree progressively forms, the Surface of fly ash was erosion, the rod-like and tabular MKP crystalline is present.

Online publication : 2013
Publication type : full_text
Public price (Euros) : 0.00