Magnesium oxychloride cement concrete

Abstract

The scope of magnesium oxychloride (MOC) cement in concrete works has been evaluated. MOC cement concrete compositions of varying strengths having good placing and finishing characteristics were prepared and investigated for their compressive and flexural strengths, E-values, abrasion resistance etc. The durability of MOC concrete compositions against extreme environmental conditions viz. heating-cooling, freezing-thawing, wetting-drying and penetration and deposition of salts etc were investigated. The results reveal that MOC concrete has high compressive strength associated with high flexural strength and the ratio of compressive to flexural strength varies between 6 and 8. The elastic moduli of the compositions studied are found to be 23-85 GPa and the abrasion losses between 0⋅11 and 0⋅20%. While alternate heating-cooling cycles have no adverse effect on MOC concrete, it can be made durable against freezing-thawing and the excessive exposure to water and salt attack by replacing 10% magnesium chloride solution by magnesium sulphate solution of the same concentration.

Recent development in magnesium oxychloride cement

“…As a potential building material, MOC exhibits comparatively high flexural strength (≥4 MPa), high compressive strength (≥69 MPa), and high elastic modulus (70–85 GPa) . The strength development of MOC is mainly affected by the formed hydration products and microstructure of MOC.…”

Growth and characterization of the NiAl–NiAlNb eutectic structure

“…A promising method of obtaining NiAl-based alloys with improved mechanical properties is the use of controlled solidification of eutectic alloys, which would generate a composite structure formed by NiAl and another phase, preferably more ductile. In order to examine possible eutectic transformations, several authors have investigated alloys composed of NiAl and refractory metals, like Cr, Mo, Ta, W and Nb [6][7][8][9][10][11]. Based on the above information, the purpose of this work is to investigate the obtaining of composite materials formed in the Ni-Al-Nb system, determine the composition and temperature of the L-NiAl+ NiAlNb eutectic transformation and evaluate its solidification microstructures.…”

Preparation and properties of modified magnesium oxysulfate cement derived from waste sulfuric acid

“…Magnesium oxysulfate cement, an air-dried magnesia-based cementing material similar to magnesium oxychloride (MOC) cement, is usually prepared using a combination of the active magnesia (MgO) and magnesium sulfate solutions (Beaudoin and Ramachandran, 1978;Daspoddar et al, 1992;Misra and Mathur, 2007). Owing to its superior properties compared with ordinary Portland cement, such as its low density, fire resistance, and low thermal conductivity, MOS cement can be used to render wall insulation panels, interior plaster, fire resistant materials and to decorate panels.…”