Effect of SO₃ on modification of C₃S and property in high magnesium content clinker

Modification of C₃S and impact properties of cement clinker by addition of SO₃ into high MgO content were investigated. Modification of C₃S in clinker was characterized with XRD. Paste compressive strength and combined water were measured. Results showed: 1% and 2% addition of SO₃ had no negative impact on the formation of C₃S with the evidence of low f-CaO content in clinker; addition of SO₃ could improve the later strength of clinker. The paste compressive strength in 3 and 28 d were separately improved by 8% and 5% with 2% addition of SO₃. The degree of hydration was enhanced by increasing the SO₃ addition with high ettringite content hydration products.