STRENGTH ACTIVITY INDEX AND PROPERTIES OF SPENT BLEACHING EARTH ASH
Keywords:Spent bleaching earth ash, Pozzolan, Strength activity index, Cement replacement
Spent bleaching earth ash (SBEA) is a recycled product from spent bleaching earth (SBE) waste. Despite the disposal of SBE waste at landfills which can cause pollution, the waste can be processed to produce SBEA which is currently used in the construction industry. The strength activity index of ground spent bleaching earth ash (GSBEA) has been investigated in this study. The chemical, mineralogical, physical, and microstructural properties of GSBEA have been determined. The GSBEA was used at 10, 20, 30, 40, and 50% as partial cement replacement. The strength activity index (SAI) of GSBEA was determined according to ASTM C311 at 7, 28, and 90 days. SA scanning electron microscope equipped with energy dispersive x-ray spectroscopy (SEM/EDX) was used to determine the effect of GSBEA on the microstructural properties of mortar paste at 90 days. The GSBEA can be used up to 40% due to its better performance in SAI values compared to other mortars which were 100.58%, 135.17%, and 136.17% at 7, 2,8 and 90 days respectively. This finding is supported ban a SEM/EDX micrograph image of a mortar containing 40% of GSBEA, which revealed the calcium silicate hydrate formation after 90 days of curing.