CIFICEN   24414
CENTRO DE INVESTIGACIONES EN FISICA E INGENIERIA DEL CENTRO DE LA PROVINCIA DE BUENOS AIRES
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Hydration of ternary cements elaborated with limestone filler and calcined kaolinitic clay
Autor/es:
TIRONI, ALEJANDRA; SCIAN, A. N.; IRASSAR, E. F.
Lugar:
Beijing (China)
Reunión:
Congreso; 4th International Congress on the Chemistry of Cement (ICCC 2015); 2015
Institución organizadora:
ICCC
Resumen:
This paper describes the performance of ternary blended cements made with calcined clays (CC),limestone filler (F), and two different Portland cements (PC). CC was obtained from kaolinitic clay (low grade of kaolinite, and quartz as main impurity) calcined at 750 ºC during 4 hours. The metakaolinite containing in the CC (44%) has a high pozzolanic activity. Portland cements with low and medium C3A-content were used. Ternary blended cements were prepared replacing CC (0 to 30%) and F (0 to 10 %) by mass in both PCs used.Pozzolanic activity of blended cements was measured using Frattini test and in terms of compressive strength at 2, 7 and 28 days. The microstructural change was followed by XRD to determine the assembly of hydration products, the porosity determined by mercury intrusion porosimetry (MIP) The results of this study show that the pozzolanic activity of CC is more effective for low C3A-content in PC. The presence of limestone filler stimulates the pozzolanic reaction after 7 days for both PCs. The limestone filler in ternary blended cements has a large contribution to compressive strength when the PC used has medium C3A - content. The combination of CC and F increases the amount of AFmphases. At all ages, blended cements with 5% F and 15% CC present the best performance. The C3A content in the Portland cement is a significant variable to be considered for the formulation of blended cements with CC and F. The coupled effect of CC and F increased when increased the C3A-content in Portland cement.