PERFORMANCE CONCRETE CONTAINING COAL BOTTOM ASH ON THE STRENGTH PROPERTIES UNDER ELEVATED TEMPERATURE AND VARIOUS COOLING METHOD

In recent years, excessive quantities of industrial by-products dumped from coal-thermal power plants have resulted in environmental contamination and landfills. Recycling industrial waste will help to minimise the consumption of cement in concrete. Hence, carbon dioxide emission from cement production can be reduced simultaneously. The current trend in the construction industry has also highlighted the use of silica-rich supplementary cementitious materials from industrial wastes in concrete production. Numerous studies have also validated the properties of these potential waste materials. Yet, there is less information on coal bottom ash (CBA) performance in concrete exposed to elevated temperature as partial cement replacement. Therefore, this study was done to investigate the strength performance of CBA subjected to elevated temperature with a different cooling method. Several tests were conducted to examine the performance of CBA concrete at elevated temperatures of 200o C, 400o C and 600o C; compressive strength, visual appearances and mass loss. The test of concrete specimens with a replacement proportion of 5%, 10%, 15% and 20% is measured and compared with those of the control concrete specimens. Replacement level of 5% with CBA had shown comparable strength value with the control specimen, even after the elevated temperature up to 600o C. In addition, the characteristics of CBA particles having high water absorption properties have strongly influenced the overall strength performance in concrete. Therefore, it is strongly suggested to reduce the particle size of CBA before being utilised in concrete.