Effects of Calcined Muck-Dolomite on Strengths and Expansion Properties of Cement Mortar

CHEN Deng; SONG Xu-yan; HE Zhi-hai

doi:10.11988/ckyyb.20191066

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Journal of Changjiang River Scientific Research Institute ›› 2021, Vol. 38 ›› Issue (1) : 146-150. DOI: 10.11988/ckyyb.20191066

HYDRAULIC STRUCTURE AND MATERIAL

Effects of Calcined Muck-Dolomite on Strengths and Expansion Properties of Cement Mortar

CHEN Deng^1,2, SONG Xu-yan¹, HE Zhi-hai³

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Abstract

Dolomite was modified through calcination mixed with muck. The effects of calcined muck-dolomite on the strength and expansion properties of cement mortar were investigated. The hydration products of cement containing calcined muck-dolomite were examined by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS). Results show that β-C2S and C12A7 were generated in calcined muck-dolomite, and the content of β-C2S and C12A7 increased with the rising of calcination temperature. The incorporation of calcined muck-dolomite improves the strengths of blended cement mortar effectively at later age. Cement mortar containing 10% calcined muck-dolomite even gain a higher strength at 90 d than pure cement mortars. In addition, the hydration of MgO in calcined muck-dolomite gave rise to Mg(OH)₂, resulting in the expansion of cement mortars, and the expansion rate augmented with the increase of dosage of calcined muck-dolomite. The research finding is of referential value for promoting the application of dolomite in cement concrete and for reducing the pollution of construction wastes.

Key words

muck / dolomite / calcination / strength of cement mortar / expansion properties

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CHEN Deng, SONG Xu-yan, HE Zhi-hai. Effects of Calcined Muck-Dolomite on Strengths and Expansion Properties of Cement Mortar[J]. Journal of Changjiang River Scientific Research Institute. 2021, 38(1): 146-150 https://doi.org/10.11988/ckyyb.20191066

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