INVESTIGATION OF CRUSHED RED BRICKS AS LIGHT WEIGHT AGGREGATES IN CONCRETE

Abstract

Lightweight aggregate is a type of coarse aggregate that is used in the production of lightweight concrete products such
as concrete block, structural concrete, and pavement [1]. Most lightweight aggregate is produced from materials such
as clay, or shale. Blast furnace slag, natural pumice, vermiculite, and perlite can be used as substitutes; however, the
light weight aggregate has properties similar to natural aggregate, but it produces less dense and therefore yields a
lighter concrete product. The self-weight of normal concrete is estimated by more than 75% of the total dead load and
more than 50% of the total load of the structure [2]. So the use of light weight concrete will reduce the total load of
structure as well as the design cost. It can also be used in concrete block to reduce the self-weight of partition walls.
Sample of waste traditional red bricks has been crushed to the normal sizes of aggregate particles similar to natural
aggregate used. Then same mixes design are prepared for normal and crushed bricks aggregate to detect and compare
the weigh and properties of fresh and hardened concrete. The results have showed that the weight of concrete reduced
by 26%, that is mean one quarter of the normal concrete, when crushed bricks used as light weight aggregate, while
the strength is reduced by 24% at 28days. Also the workability is reduced when using light weight concrete in spite of
using saturated and surface dry crushed bricks as light weight aggregate and this may be due to angular shape and
surface texture.
It is recommended to use waste traditional red brick as crushed light weight aggregate since it reduces the self-weight
of concrete by one quarter which may suit block manufacturing as well as low strength concrete.