Mechanical strength of lightweight cylindrical aggregates

Purpose This study investigates the mechanical behavior of rubberized concrete aggregates, focusing on the effects of lightweight particle content, cohesive strength and compression speed on the compressive strength of lightweight cylindrical aggregates. It addresses a critical gap in understanding inter-grain interactions and material behavior under varying conditions. Design/methodology/approach Three-dimensional discrete element simulations were used to model lightweight cylindrical aggregates including primary particles, divided into heavy and light particles with different stiffness levels. Uniaxial compression tests were performed while systematically varying lightweight particle content, cohesive strength and compression velocity. The study focused on the compressive strength and interactions among heavy–heavy, heavy–light and light–light particles. Findings The results show that increasing lightweight particle content reduces compressive strength while compression speed significantly enhances the mechanical behavior of lightweight cylindrical aggregates. Compressive strength was primarily governed by interactions among heavy–heavy particles, shifting as lightweight particle content exceeds 33%. Remarkably, the normalization between the aggregate compressive strength and the particle cohesive strength may be well expressed as a nearly linear increasing function of the compression velocity for all values of the lightweight particle content. Originality/value Our research emphasizes the potential for tailoring rubberized concrete’s properties by optimizing lightweight particle content, cohesion and loading conditions. These findings provide insights into the design of sustainable concrete materials with applications in lightweight construction.