INGENIEUR
Bottom ash from the waste recycling factory
more coarse and bigger in size than FA ranging
from sand to gravel sizes. BA is chemically inert,
highly fused and less pozzolanic compared with
FA. In general, particles of BA are dark, angular
shape with a porous texture and a rough surface.
BA grain sizes are as listed in Table 1.
Figure 1 displays the particle size comparison
of BA and natural sand in a similar range and
correlation. This test was performed by using
sieves of different sizes allowing measurements
of 150μm, 300μm, 600μm, 1.18mm, 2.36mm,
5mm, and 10mm. The density of BA and natural
river sand was determined from their weight and
volume (see Table 2). The smooth curve in Figure 1
shows that BA has the ideal quality to enhance the
strength of concrete. Based on Figure 1 and Table
2 data, BA’s physical characteristics observed
were almost similar to natural river sand with high
content of minerals. BA is therefore a possible
suitable material to be used in construction and
manufacturing as a replacement for natural sand.
According to Novell et al. (1991), BA has a
porous structure with popcorn-like particles and
low specific gravity causing the material to be
degraded easily under loading or compaction.
Earlier studies have shown that BA has a specific
gravity between 1.39 and 2.66. This range
of values arises from different sources of the
material. The specific gravity was determined
using pycnometer and the results were tabulated
in Table 2. The specific gravity of BA coarse
aggregate is lower compared with fine aggregate
and it is more suitable to be used as a construction
mix particle (Andrade et al, 2007). Whereas
fine BA aggregates are suitable for use in road
surfacing and manufacturing bricks.
Table 2: Density and specific gravity of
BA and natural river sand
Parameter
Bottom
Ash
Natural River
Sand
Density, kg/m 3 641.03 1223.78
Specific Gravity 2.21 2.81
Source: https://iopscience.iop.org/
article/10.1088/1757-899X/160/1/012056/pdf
64 VOL 82 APRIL-JUNE 2020