J. Paya et al., COMPARISONS AMONG MAGNETIC AND NONMAGNETIC FLY-ASH FRACTIONS - STRENGTH DEVELOPMENT OF CEMENT FLY-ASH MORTARS, Waste management, 16(1-3), 1996, pp. 119-124
Magnetic extractions from aqueous-fly ash suspensions produced magneti
c and non-magnetic fly ash fractions. Several fractions were obtained
from an original fly ash (T0), from T0 and further grinding, and from
a ground fly ash (T6O). Magnetic and non-magnetic samples were charact
erized: chemical composition, granulometric data, specific gravity and
specific surface area. Workability studies on mortars containing thes
e fractions were carried out. Generally, non-magnetic fractions yielde
d mortars with similar or higher flowability than mortars containing t
he corresponding magnetic fractions. On the other hand, compressive st
rength development studies showed that non-magnetic fractions are more
pozzolanic than magnetic ones; moreover, optimum replacing percentage
of cement by fly ash fractions was 45% for non-mechanically treated s
amples, whereas for ground fractions optimum values were 30% for non-m
agnetic samples and 45% for magnetic ones. Copyright (C) 1996 Elsevier
Science Ltd