Abstract:
With technological advancement on the rise, manual crushing of bricks is gradually being
replaced by machine crushing to obtain coarse aggregates for construction. However,
properties of the brick aggregates obtained from these two methods vary which in turn,
may affect the properties of the concrete matrix as well. This study represents a
comparison between the machine crushed and manually crushed brick aggregates to be
used as coarse aggregates in preparation of concrete. Four types of bricks, namely first
class, second class, picket (over burnt) and ceramic were investigated, and each was
crushed both manually and mechanically to a usable form of aggregates. The physical and
mechanical properties of the brick aggregates derived from the two methods were tested
and compared. In all types of brick, aggregates size, shape and strength properties such as
flakiness and elongation indices, aggregate impact and crushing values and Los Angeles
abrasion value showed lower values for manually crushed aggregate indicating better
properties compare to machine crushed aggregates. This was evident while comparing
compressive and tensile strength of concrete prepared with both manually and machine
crushed first class and picket brick aggregates. Concrete with manually crushed brick
aggregates showed marginally higher compressive and tensile strength in both types of
brick aggregates.
