Evolution law and transformation mechanism of force chains in the flow of photoelastic particles under a flexible barrier

Abstract

The essence of large deformation flow in loose geological bodies lies in the breaking and rebuilding of force chains at the microscopic scale. Therefore, it is crucial to investigate force chains during particle flow processes. This study focuses on particle flow during the ore drawing process, develops a photoelastic experiment model, investigates the evolution law of force chains, reveals the transformation mechanism of strong and weak force chains, and provides insights for removing particle blockage in mining engineering. The results show that strong force chains are primarily located on both sides of the model, with fewer numbers, and extend toward the side boundaries in a direction close to 70°. Weak force chains are predominantly distributed in the middle section of the model, with numerous and uniformly developed directions. In addition, under the effects of self-organization and hetero-organization, the particles' sliding and rolling cause the buckling of force chains and the rearrangement of particles, resulting in the transformation between strong and weak force chains and accelerating the particles' flow. The research results deepen the understanding of the granular material large deformation flow-slip problem and provide a reference for similar engineering analyses.