Effect of Calcined Coal Gangue on the Mechanical Property and Microstructure of Magnesium Phosphate Cement

Abstract:

Calcined coal gangue was used as active addition of magnesium phosphate cement (MPC). Influence of calcined coal gangue addition on the setting time, mechanical property, mineral phase, and microstructure of MPC had been studied. The prescription was designed as following: the ratio of mono ammonium phosphate to magnesia was 0.25 in mass, additive amount of calcined coal gangue was 0%, 10%, 20%, 30%, 40% to the total mass of magnesia and mono ammonium phosphate respectively, borax additive amount was 0.06 to other raw materials. The result show that calcined coal gangue could extend the final setting time and improve the early strength of MPC. The MPC obtained its maximum compressive strength of 94.9 MPa and 95 MPa with the calcined coal guage content is 0% and 10% respectively. The particles of calcined coal gangue powder filled in the voids of cement matrix as framework and had effect on microstructure. Furthermore, calcined coal guage might participate the hydration reaction in a long age and form a cementing product which result in improvement of MPC’s long time strength.

• Periodical: Applied Mechanics and Materials (Volumes 174-177)
• Pages: 943-946
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.174-177.943
• Online since: May 2012
• Authors: Lei Hou, Jin Hong Li, Ling Xin Tong, Qi Zhang
• Keywords: Calcined Coal Gangue, Magnesium Phosphate Cement, Mechanical Strength, Microstructure

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DOI: 10.1016/s0008-8846(00)00419-1

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