Abstract
The dephosphorized slag obtained from steel making process is a promising material for use as admixture in portland cement concrete. The synthesized belite (β-2Ca0·SiO2) admixture was developed by burning the dephosphorized slag at 1100°C. This synthesis contains a large amount of β-C2S, synthesized by nothing free-CaO components in the deshosphorized slag. The optimum mixing ratio and amounts of SiO2, CaO and the optimum burning temperature were determined. Though strength of mortar replaced OPC by 10-30mass% of the synthesized belite admixture was low at shorter ages, but it was expected to increases the strength at later ages. The adiabatic temperature rise was showed lower than OPC mortar. These properties was contributed by the existence of β-C2S in the synthesized belite admixture.
