Effect of delayed addition time of synthesized SSPF condensate on the durability of sulphate resisting cement pastes incorporating micro-silica

The work aimed to evaluate the effect of delayed addition time of SSFP condensate on the physico-mechanical characteristics and durability of 10% micro-silica (MS)-sulphate resisting (SRC) cement pastes immersed in 4% MgCl2 or 4% MgSO4 solutions or at elevated temperatures up to 800 °C. The results show that the compressive strength and bulk density increase, whereas, the total porosity decreases with 1.5% SSPF at 10 min delayed addition time (optimum mix) up to 90 days. The compressive strength of thermally treatment cement pastes with 1.5% SSFP increases up to 450 °C, then decreases up to 800 °C. Presence of 1.5% SSFP with 10 min delayed addition time work together to produce a compact cementing structure, which decreases the accessibility of the penetration of chloride as well as sulphate ion penetration and enhances the durability, hence the total chloride and sulphate contents diminished.