In concrete production, shape of aggregate reflects the quality of concrete produced. The well-shaped aggregates are said to produce high quality concrete by reducing water to cement ratio. On the contrary, poor-shaped aggregates often require higher water to cement ratio in concrete production. Conventionally, the quality of concrete is determined by calculating the ratio aggregate classifying systems of well-shaped aggregate to poor-shaped aggregate contained in concrete. This procedure is slow, highly subjective and laborious, which is inefficient and expensive.
As a major factor in the production of high quality concrete, the aggregates need to be classified before used. The conventional classification method of the aggregates is done manually. The method is slow, highly subjective and laborious. The method can be replaced by using digital image processing technique and neural network, known as automatic classifier.
Quarries provide earth materials such as rotary kiln processing system sand, clay, gravel and crushed rocks that will be processed further into raw material inputs for buildings and construction, agriculture and industrial processes. The demand for these materials is derived by the demand for the goods and services that these materials provide, with each user industry defining specifications fit for their final products (Rajeswari et al., 2004). The rapid growth from construction sector automatically accelerates and gives rise for higher demand for aggregates which is the major constituent of construction particularly for concrete.
At least three-quarters of the volume of concrete is occupied by aggregates and hence it is not surprising to know that its quality is of considerable importance (Neville, 1995). Report from Rajeswari (2004), showed that the nature and the degree of stratification of rock deposit, the type of crushing plant used and the size reduction ratio as amongst the key factors that greatly influence the shape of aggregate particles and the quality of fresh and hardened concrete. The ability to produce high strength concrete with good bonding characteristics and at the same time maintaining the workability of fresh concrete and adequate strength for the hardened concrete is an excellent contribution to the science of concrete technology which is known racing for higher strength. Similarly, report from Hudson (1995, 1996) clearly showed that improvement in the shape of aggregates nickel ore beneficiation had been proven to be a major factor in the reduction of the water to cement ratio needed to produce a concrete mixture. This high quality aggregate also has the ability to decrease the cost of production and placement of concrete and hence increase the characteristics of the concrete such as strength and its overall quality.