Civil Engineering Reference
In-Depth Information
Table 2.26 Physical properties of porous ceramic waste aggregate, natural coarse aggregate and
a commercial lightweight aggregate (Suzuki et al.
2009
)
Properties
Ceramic waste
aggregate
Natural coarse
aggregate
Natural fine
aggregate
Commercial
lightweight aggregate
Specific gravity
2.27
2.92
2.62
1.27
Water absorption
capacity (%)
9.31
0.88
2.41
12.2-22.3
Fineness modulus
6.66
6.51
3.21
6.47
Crushing rate
21.4
7.86
-
37.0
Fig. 2.11 Grading curve of
porous coarse ceramic
aggregate (PCCA) and of
natural coarse aggregate
(Suzuki et al.
2009
)
production of concrete. These are: ceramic bricks; white stoneware once fired;
sanitary ware; white stoneware twice-fired. The major oxide constituents present in
these waste types are silica and alumina. The major mineral phases present in all
the waste types are quartz and feldspars. All the waste types were crushed with a
jaw crusher to make the ceramic aggregate. The coarse and fine sized aggregates
and ceramic powder were obtained after sieving. The densities of sand and coarse
sized ceramic waste were 2,210 and 2,263 kg/m
3
respectively. The water
absorption capacities of sand and coarse sized ceramic aggregates were 6.1 and
6.0 % respectively.
De Brito et al. (
2005
) reported the use of ceramic hollow bricks fragments from the
making of partition walls as a coarse aggregate for the production of non-structural
concrete for pavement slabs. To characterise ceramic waste aggregate along with
natural aggregate, the volume index of the different size fractions, the compacted
oven dry bulk density of both types of aggregates, the compacted air-dried and water
saturated bulk densities of waste ceramic aggregate, the specific densities of both
types of aggregates at dry and saturated surface dry conditions, and the water
absorption capacity were measured. The results are presented in Table
2.28
.
The volume index indicates the shape of the particles: aggregates nearly
spherical have an index near 1, compared to elongated ones with a smaller index.
From the results of volume indices of various size fractions, the authors conclude
that the grinding process of the recycled aggregates is a critical parameter since it
strongly affects the volume index and therefore deserves further study. From the
