Particle breakage investigation of construction waste recycled aggregates in subgrade application scenario

Abstract

This paper investigated the particle breakage of recycled aggregates from construction and demolition wastes used as subgrade materials. The laboratory tests include two steps, namely, specimen preparation and dynamic triaxial tests. From the view of particle breakage, multiple specimens with different gradations and compositions were analyzed comparatively using two preparation methods, including impact compaction and vibrating compaction. In the dynamic triaxial tests, the permanent deformation, volumetric strain and particle breakage indexes under different loading conditions were measured, and the prediction model was established to determine the stress state-breakage indexes via the correlation analysis. The gradation of tested aggregates designed by the continuous equation after experiments can be calculated by the measured breakage indexes. Relative breakage rates would be close to the upper limit value with the increasing of the loading cycles, and a determination method of the stable gradation was proposed based on the fractal theory.