Jordan Journal of Civil Engineering

Paper Detail

A Study to Improve Clay Soil by Using Calcite Additive in Ceramic Tile Manufactory

Volume 11, No. 3, 2017
Received: 2017/06/11, Accepted:


Maiasa Melhem; Ibrahim Hammoud;


Many researchers have studied the important effect of calcium carbonate addition on fine soils. They have proved a reciprocal relation between calcium carbonate (calcite) content in clay and its plasticity index. We aim in our research to support the industry by improving available raw materials through adding artificial or natural additives, which positively affect the specifications of the final product. So, we focus on changing the plasticity of clay which is considered a very important property in the manufactory of ceramic tiles. The samples of clay have been chosen from some Syrian clay sites. This clay was previously unacceptable in ceramic industry, because it couldn’t achieve the minimum requirements for ceramic tile industry standards. We have classified the soils according to the Unified Soil Classification System (USCS) after applying the essential tests on clay soil. Then, we have prepared the reference ceramic tile samples (without additives) and compared them with the other samples (with calcium additives from 5% up to 30%) by applying technical tests such as: water absorption, flexural strength and linear shrinkage tests. We have achieved remarkable improvements. Flexural strength has increased while water absorption has decreased. The best percentage for calcium carbonate additive is about 5%, which ensures technical properties’ matching with international standards. All changes on strength, shrinkage and water absorption values became steady after a percentage of 25% of calcite additives. The efficiency of the additives correlates both chemically and mineralogically with soil composition.


Ceramic tile, Clay, Calcite, Flexural strength, Linear shrinkage, Water absorption