Reaction Mechanism Analysis of Phosphorus Slag - Fly Ash - Phosphorus Gypsum - Cement Foamed Concrete

In this study, phosphorous slag powder, fly ash and cement were used as composite cementing materials, and phosphogypsum was used as the activator of phosphorous slag powder and fly ash to stimulate their activity. The hydration reaction of cement, phosphorus slag powder, fly ash and phosphogypsum was studied. The results show that the hydration products of cement, cement + phosphorous slag powder, cement + phosphorous slag powder + fly ash, and cement + phosphorous slag powder + fly ash + phosphorous gypsum have the same mineral composition but different relative content. The hydration samples of cement, cement + phosphorous slag powder, cement + phosphorous slag powder + fly ash, and cement + phosphorous slag powder + fly ash + phosphogypsum have certain differences in microstructure and quantity, especially ettringite. Cement hydration can stimulate the activity of phosphorus slag powder and fly ash, in turn, the addition of phosphorus slag powder, fly ash and phosphogypsum can promote the hydration process of cement, improve the quality of hydration products, and improve the density of concrete structure.