Evaluation of the degree of activation of a thermally treated clay used as an addition for the manufacture of an eco-cement

Abstract

The pozzolanic activity is the chemical process which generates,during the hydration of cement, new calcium silicate hydrates(CSH). This work aims to activate thermally clay in order toobtain an artificial pozzolan which can be incorporated tomanufacture cement obeying to standards. The optimization ofthe calcinations is achieved by varying the temperature andholding time and through monitoring structural changes by DSC,TGA, FTIR as well as by assessing the evolution of mechanicalstrengths. It is shown that the optimal pozzolanicity is obtained ifthe clay is calcined at 700 ° C for 5 hours