Effect of BaO on mechanical and hydration characteristic of C8A6P as predominant mineral in phosphoaluminate cement

Phosphoaluminate cement clinker (PAC) was one type of cementitious material due to its high durability and mechanical performance. As the predominant mineral phase in PAC, the high-temperature formation and property of calcium phosphoaluminate mineral (C8A6P) were related closely with hydration and mechanical characteristic for PAC. Thus, the influence of BaO on the performance of C8A6P mineral phase was investigated carefully in this paper. It was found that BaO of 17.5–20% content could endow C8A6P mineral with predominant mechanical performance. This was due to the fact that C8A6P mineral was activated by BaO. Excessive BaO would lead to the formation of new unexpected phase BaO·Al2O3. The limited solid solubility of BaO in C8A6P mineral was 20%. The addition of BaO changed the ratio of hydration products of C2(A,P)H8 and C(A,P)H10 for C8A6P mineral.