Civil Engineering Reference
In-Depth Information
(a)
0-40mm
(b)
10-25 mm
(c)
4-12 mm
Fig. 3.2 Compositions of CDW with different size range Gonzalez-Fonteboa and Martinez-
Abella (
2008
)
Table 3.3 Composition of two size fractions of CDW aggregate (Sani et al.
2005
)
Constituents
Amount (%) in
Sand (0-5 mm)
Gravel (5-15 mm)
Masonry
32
25
Inert
30
29
Concrete
35
45
Bitumen
2
0.5
Wood, glass, plastic etc.
1
0.5
CDW aggregates may comprise three types of particles: some particles of
natural coarse aggregates are held together and surrounded fully or partially by a
layer of mortar and some lumps of mortar embedded with varying proportions of
smaller natural aggregates (Akbarnezhad et al.
2011
).
3.4 Attached Mortar Contents in CDW Aggregate
and Methods of Evaluation
The properties of CDW aggregate are dependent on the amount of mortar content
in the CDW aggregate. The amount of mortar content in CDW is dependent on the
number of crushing processes in the production plants. The attached mortar con-
tent in the CDW aggregate can be reduced by increasing the number of crushing
processes. However, increasing the number of crushing processes increases the
