Properties of Cement Mortar Containing Rubber Ash as Sand Replacement

Discarded scrap tyres have become one of the major environmental problems nowadays. There has been increasing public worry about the mining of natural resources in recent years. In order to minimize the consumption of natural resources, rubber ash has been postulated as a potential material for partial replacement of sand in concrete materials especially for applications which are subjected to impact and vibration such as road and bridge construction. Thus, it contributes to the development of the construction industry in a sustainable way. This paper mainly emphasizes on the use of rubber ash from waste tyres in cement mortar. 100mm cubic specimens were produced by adding rubber ash volume ratios of 0%, 3%, 5% and 7% as sand replacement in M30 quality cement mortar. A compressive stress test and a density test were conducted at the end of 7, 14, and 28 days. The result shows that 5% is the optimum value for sand replacement in the cement mortar. Therefore, rubber ash is acceptable to be used as sand replacement.