Clay for brick making is prepared differently in a rural environment – manually in small brick yards – and near towns and urban areas mostly in large-scale factories employing heavy duty machinery and equipment. Since modern clay works, quite often cannot satisfy the demand for brick and tiles, rural brick makers are increasingly playing an important role as suppliers and thus, are confronted with the demand for good quality fired clay products.
Brick makers are faced with the challenges of producing bricks of satisfactory quality efficiently, economically and sustainably and with particular regards to mitigating environmental damage.
The main technical problems that brick making units suffered from are poor quality, weak bricks, a high breakage rate, no standardization and a complete lack of knowledge and experience of how to correctly use bricks in construction. The poor quality and high breakage rate were normally caused by selecting inferior quality clays and/or faulty production techniques during the clay preparation, moulding, drying and firing stages.
Before sending the soil to the laboratory the first is to test the soil sample using simple field tests that require no special equipments. These tests are quite satisfactory but occasionally the results of these field tests can be quite misleading if the person have no experience in brick making.
The second method is to check the soil in the laboratory for suitability in brick making. The results of the tests are usually quite accurate and can be very informative if they are interpreted well.
The last and the most important (usually ignored by all) is to simulate the laboratory conditions into pilot plant scale. Most of the soil testing units do not perform this step due to paucity of the required facilities. However pilot trials are extremely necessary to have a feel of the production process and to actually feel the product expected during the actual production process.