Study on microstructures and macro-properties in cement-based materials adding phosphorous slag

Abstract

Microstructures and macroproperties of cement-based materials adding phosphorous slag were studied in this paper. As the results show that the hydration heat decreased with the increase of the mix amount of phosphorus slag, and the reducing rate of hydration heat was lower than that of volume percentage. Set cement hydration products include more tabularly cumulated Ca(OH)2 crystals. The hydration products start to form compact tabular structures and the number of holes reduces visibly at the age of 28 days. Meanwhile, phosphorous slag concrete has good frost resistance and anti-permeability. Mixing fly ash and phosphorus slag can improve the wear-resisting strength of the concrete. The self-grown volume of phosphorus slag concrete shrinks slightly in the early age the expansion rate tending to be stable. Air shrinkage of the phosphorus slag concrete is slightly lower in the early period, and it is fairly the same as that of the fly ash concrete in late period.