Reactivity of blended SCMC for sustainable ternary cements

Abstract

The Cement industry is responsible for huge CO2 emission; still, numerous efforts are being applied to increase the efficiency of cement plants. The CO2 emissions from cement production can also be reduced by replacing clinker content with supplementary cementitious materials (SCMs). Ternary cements are one of the most efficient ways to reduce the clinker content up to 50% without affecting the performance of cement. Before replacing clinker with any of the SCM’s, their reactivity must have to be studied properly. This paper will focus mainly on the reactivity of blended SCMs for ternary cements. Reactivity of different blends having calcined clay with limestone and fly ash with slag was studied in the presence of calcium hydroxide using isothermal calorimeter. The effect of different proportions of calcium hydroxide, accelerators, and temperature on reactivity was also studied. Additionally, the compressive strength of cement mortar cubes having 50% replacement of OPC was studied and further, the reactivity data of blends from calorimeter was compared with the compressive strength of mortars. It was observed that the compressive strength of calcined clay and limestone cement with different proportions was ranging from 38.17 to 32.70 MPa. Where as in the case of fly ash and slag cement having different proportions was ranging from 29.26 to 43.73 MPa. A reasonable good correlation was observed with the calorimeter energy data and strength.