Mitigating calcium oxychloride formation in cementitious paste using alternative supplementary cementitious materials

Supplementary cementitious materials (SCMs) are known to reduce calcium oxychloride (CAOXY) contents in cementitious pastes. However, when availability or cost precludes the use of traditional SCMs, such as fly ash, mitigation could be provided through alternative materials. Fly ash (FA), rice husk ash (RHA), bottom ash (BA), limestone filler (LS), nepheline syenite filler (NS), sandstone filler (SS), and silica flour (SFL) were evaluated for CAOXY mitigation in cementitious paste using low-temperature differential scanning calorimetry, reactivity testing, thermogravimetric analysis, and compressive strength testing. The order of CAOXY mitigation from least to most effective is SS, LS, SFL, NS, BA, FA, and RHA.