The effect of different ages and water-binder ratios on the mechanical properties of circulating fluidized bed combustion desulfurization slag cement-soil

In this study, the effect of different ages and water-binder ratios on the mechanical properties of circulating fluidized bed combustion (CFBC) desulfurization slag cement-soil were discussed. Particle size distribution analysis, unconfined compressive strength test, scanning electron microscopy (SEM) and X-ray diffraction (XRD) tests were conducted to determine the outcome. The mechanical grinding treatment of CFBC desulfurization slag was found to improve its activity. The mechanical grinding time was controlled at 55 min. The mechanical grinding time did not exceed 75 min. With the increase in the total content of cementing materials, the unconfined compressive strength increased. The different cementing materials content of cement-soil corresponds to an optimal cement-binder ratio. At the age of 60d, the strength of test block which having 25 % and 30 % of total cementing materials respectively were determined to be 1.15 and 1.42 times higher than the cementing materials with 20 % content. Moreover, the strength was greatly improved. The total dosage of cementing materials and water-binder ratio must be controlled in the range of 25 % − 30 % and 1.0–1.3, respectively.