2.4. Physical properties of sintered fly ash samples
Dry density (apparent specific gravity) and water absorption of sintered fly ash samples were determined by measuring the dry mass mdry, immersed mass mimm and 24 h saturated surface-dry mass msat (Neville, 1994). Using Archimede’s principle individual particle densities were calculated from mdry msat − mimm (g cm−3) and the 24 h water absorption value was calculated from msat − mdry mdry × 100% Sample shrinkage was determined from the differences in green
and fired sample diameters.
2.5. Micro-structural and mineralogical characterisation of sintered fly ash samples
Fracture surfaces of crushed sintered samples were gold-coated and examined by scanning electron microscopy (SEM, JEOL, JSMT220A).Sintered samples were ground to