Clinker ash is coal ash that has collected in the water tanks at the bottom of boilers in a coal-fired power station and is crushed to the size of sand or gravel. It has a porous and complex particle shape, is lightweight, has excellent permeability, and high shear strength. The purpose of this study is to compare the mechanical properties of clinker ash and construction-generated soil in alternating layered and mixed conditions, and to investigate the slope stability when these materials are used as embankment materials. Mechanical properties were investigated by triaxial compression tests, and slope stability was investigated by circular slip analysis. As a result, there was no difference in the consolidation termination time, and the volume change was slightly smaller for the layered structure. The shear strength was slightly higher in the layered structure at CA 10-20%, while the mixed structure exhibited less volumetric strain contraction at CA 50%. The stability analysis of the embankment slope indicated that the minimum factor of safety was slightly higher for the mixed structure, but that the mixed structure had greater resistance in the clinker ash layer, and that safety could be improved depending on its placement.
