Comparison of Shape Parameters and Laboratory Performance of Coarse Aggregates Produced from Different Types of Crushing Operations

Abstract

The current study compared aggregate shape parameters and laboratory performance of coarse aggregates produced from two different types of crushing operations. The coarse aggregates from two type of crushing operations, (1) a series of jaw (J)-cone(C)-vertical shaft impactors (V), called JCV, and (2) a series of jaw (J) and horizontal shaft impactors (H), called JH, were selected in the present study. The coarse aggregates collected from both crushing operations were separated into five different sizes ranging from 4.75 to 25 mm. The shape parameters [angularity, texture, sphericity, and flatness (F) and elongation (E)] of different sizes of coarse aggregates were measured using the aggregate image measurement system (AIMS) device. Further, the influence of aggregate shape parameters on their packing behavior and stability were evaluated by conducting three laboratory tests: void in coarse aggregate (VCAdrc), angle of repose (AoR), and the direct shear test (DST). The results showed that both the JH and JCV series of crushers produced aggregates with similar angularity; however, significant differences were observed in texture, sphericity, and F and E of aggregates. The aggregates produced from the JH crusher were found to have higher VCAdrc, AoR, and friction angle compared to aggregates from the JCV crusher. The results showed that aggregates obtained from the JH crusher may have better interlocking and stability than aggregates from the JCV crusher.