A REVIEW ON MECHANICAL CHARACTERISTICS OF NORMAL CONCRETE PARTIALLY REPLACED WITH RECYCLED CERAMICS AGGREGATES

Abstract

The quantities of ceramic wastes in our nation have been on the increase significantly (approx. 45.9 tonnes annually in Nairobi) without consideration for potential reuse or recycling, increasing the risk to public health due to the scarcity of land area. This growing problem can be alleviated if new disposal options other than landfill can be found. In addition, increased construction activity and continuous dependence on conventional materials of concrete are also leading to scarcity of these materials resulting to increased construction cost. This study aims at reviewing the past research work on the use of ceramic waste aggregate as possible partial substitute for conventional coarse aggregate in concrete. From the review, an optimum mechanical strength of recycled ceramics in concrete was identified. Recycled ceramics originates mostly from broken or leftover tiles, sanitary and kitchenware. Two different ceramics were considered as partial substitute for coarse aggregate in concrete under this review, i.e. crushed clay bricks and tiles. The replacement proportions varied from 0%, 17%, 33%, 50%, and 67% by weight for natural aggregates, while other components kept constant. A detailed analysis of the results of previous work is presented for concrete design mixes. Final tests results of this work are of importance in assessing the mechanical properties determined through splitting tensile tests, flexural tests, compressive tests and bond strength development tests at 7, 14, and 28 days. Tests results showed positive response for mechanical properties of the new concrete. The review indicates that considerable knowledge and expertise has been accumulated on the use of waste ceramic products as partial occupant of natural aggregates in concrete technology. This therefore provides better and efficient recycling and utilization of waste ceramics in our environment.