Waste Rubber Tires: A Partial Replacement for Coarse Aggregate in Concrete Floor Tile Production

Abstract

Concrete tile is one of the most used construction materials in the world. Cement and aggregate, which are the most important constituents used in concrete tile production, they are the vital materials needed for the construction industry. This led to a continuous and increasing demand of natural materials used for their production. Parallel to the need for the utilization of the natural resources emerges a growing concern for protecting the environment and a need to preserve natural resources (such as aggregate) by using alternative materials which are recycled or waste materials. In this research, a study was carried out on the use of used rubber tires as a partial replacement for coarse aggregates in concrete tile production using locally available waste tires. A review of relevant literatures was done to study previous works in the subject matter. The research was carried out by conducting tests on the raw materials to determine their properties and suitability for the experiment. Concrete mix designs are prepared using the DOE method and a total of 12 mixes were prepared consisting of two concrete grades (C25 and C30). The specimens were produced with percentage replacements of the coarse aggregate by 10, 20, 30, 40 and 50% of rubber aggregate with and without supper plasticizer (admixture). Moreover, a control mix with no replacement of the coarse aggregate was produced to make a comparative analysis. The prepared samples consist of concrete cubes, cylinders and beams. Laboratory tests were carried out on the prepared concrete samples. The lists of tests conducted are; material property, slump, unit weight, compressive strength, splitting tensile strength and flexural strength tests. The data collection was mainly based on the tests conducted on the prepared specimens in the laboratory. The test results were compared with the respective conventional concrete properties and show that there is a reduction in compressive strength of the concrete due to the inclusion of rubber aggregates. This is improved by using admixture to some extent, but lower density and enhanced ductility are the same, and there was a slight increase in flexural strength without admixture. The overall results show that it is possible to use recycled rubber tires in concrete tile production as a partial replacement for coarse aggregates. Nevertheless, the percentage of replacement should be limited to 10%.