ABSTRACT
This study aims to investigate the reuse of resources of the co-firing fly ashes from a bubbling fluidized boiler to produce controlled low-strength material (CLSM). First, we made a pozzolanic-activity test to confirm if the fly ash can be used as a raw material for making cementitious materials. After that we make samples of cementitious materials with the co-firing fly ashes taking different percentages of weights in them (5%, 10%, 15% and 20% for each) and use them to undergo the various tests including initial set time, slump flow, compression, X-ray diffraction experiments and SEM microstructure of mercury.
The result shows that the strength activity index (SAI) of the co-firing fly ashes is greater than 75 percent of the materials that can be used as the raw materials and meet the ASTM C311 standard. The results above show that co-firing fly ashes from a bubbling fluidized bed boiler can be utilized as substitution materials for cementitious materials in the controlled low-strength materials. The best substitution percentage is 15 percent.
