Effects of Curing Methods on Hydration and Mechanical Properties of Magnesium Silicate Cement

doi:10.16552/j.cnki.issn1001-1625.2024.1633

Abstract

Abstract: As a new type of green and low-carbon building material, magnesium silicate cement (MSHC) has the advantages of light, porosity, low alkalinity and low hydration heat, but it also has some problems such as slow development of mechanical properties in the early stage and easy cracking in the later stage. In this paper, the effects of curing methods such as high temperature (50 ℃) curing, high water absorbent resin (SAP) curing, SAP+high temperature (50 ℃) curing on the mechanical properties of MSHC were discussed, and the mechanism was analyzed by XRD, SEM, comprehensive thermal analysis and solid state nuclear magnetic resonance silicon spectroscopy. The results show that compared with high temperature (50 ℃) curing or SAP curing alone, SAP+ high temperature (50 ℃) curing can significantly improve the early compressive strength of MSHC, promote hydration reaction, and its 3 and 28 d compressive strength can reach 34.8 and 61.0 MPa, respectively. High temperature curing accelerates the formation of MgO-SiO₂-H₂O (M-S-H) gel. SAP+high temperature (50 ℃) curing method can more effectively promote the hydration of MgO and generate more M-S-H gel.

Key words: magnesium silicate cement, curing system, SAP, mechanical property, degree of hydration, comprehensive thermal analysis, solid state nuclear magnetism

CLC Number:

TQ177
TQ172

LI Xiangguo, BAO Luchao, HE Chenhao, ZHANG Chengshan, LYU Yang. Effects of Curing Methods on Hydration and Mechanical Properties of Magnesium Silicate Cement[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2025, 44(7): 2368-2377.

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