The combined effects of mechanical vibration and particle's geometry on entanglement, and strength in staple-like entangled granular materials: Experiments and DEM Simulations
ORAL
Abstract
Entangled granular material exhibits unusual and attractive properties and mechanisms: rare combination of high tensile strength and toughness, capabilities for reversible assembly and disassembly enabling full recyclability, damage tolerance. In this study, we used experimental tensile testing with discrete element method (DEM) simulations to investigate how mechanical vibrations, acting as an external stimuli, influence local entanglement, and tensile force chains and thereby control the tensile strength and deformability of staple-like entangled granular materials. Our results reveal that prolonged vibrations increase the entanglement density up to a steady state value, at which point the rate of entanglement equals the rate of disentanglement. Both experiments and simulations demonstrate a strong correlation between entanglement density and the tensile strength of the bundle. Vibrations can be also used to heal entangled granular matter—large defects within the bundle, several times the particle size, can be completely restored through mechanical vibration under confinement. Conversely, when the confinement is removed, we show that vibrations can completely and rapidly disassemble entangled bundles into individual particles, offering exciting perspectives in terms of reconfigurability, recyclability, as well as programmable assembly and disassembly.
*This work was supported by the US National Science Foundation (Mechanics and Materials and Structures CMMI-2033991 and CMMI-2517927). DEM simulations were performed on the Alpine high performance computing resource at the University of Colorado Boulder. Alpine is jointly funded by the University of Colorado Boulder, the University of Colorado Anschutz, Colorado State University, and the National Science Foundation (Award 2201538).
–
Publication:[1] Pezeshki, S. and Barthelat, F. (2025). Combined effects of particle geometry and applied vibrations on the mechanics and strength of entangled materials. arXiv preprint arXiv:2510.09933 (Under Review- Journal of Applied Physics) [2] Pezeshki, S., Sohn, Y., Fouquet, V., & Barthelat, F. (2025). Tunable entanglement and strength with engineered staple-like particles: Experiments and discrete element models. Journal of the Mechanics and Physics of Solids, 200, 106127. [3] Sohn, Y., Pezeshki, S. & Barthelat, F. (2025). Tuning geometry in staple-like entangled particles: "pick-up" experiments and Monte Carlo simulations. Granular Matter 27, 55.
