POZZOLAN CONTAINING ANDRADITE AND METHOD FOR PRODUCING POZZOLAN CONTAINING ANDRADITE FORMED IN SITU

摘要

The present application relates to a pozzolanic material containing at least 2% andradite (Ca₃Fe₂(SiO_-4)₃) formed in situ in its composition. The pozzolan is produced from red clay, which, after mixing with limestone (50-97% red clay and 3-5% limestone), is calcined at a temperature between 900 and 1300°C, with the in situ formation of andradite occurring. The method in question allows the use of red clay with a high Fe³⁺ content by means of the conversion of hematite (Fe₂O₃) into andradite. The final material has a gray colour and does not alter the colour of cement when added to it.