In the study of the physics of

granular material A granular material is a conglomeration of discrete solid, macroscopic particles characterized by a loss of energy whenever the particles interact (the most common example would be friction when grains collide). The constituents that compose ...

s, a force chain consists of a set of particles within a compressed granular material that are held together and jammed into place by a network of mutual compressive forces. Between these chains are regions of low stress whose grains are shielded for the effects of the grains above by

vaulting In architecture, a vault (French ''voûte'', from Italian ''volta'') is a self-supporting arched form, usually of stone or brick, serving to cover a space with a ceiling or roof. As in building an arch, a temporary support is needed while ring ...

and

arch An arch is a vertical curved structure that spans an elevated space and may or may not support the weight above it, or in case of a horizontal arch like an arch dam, the hydrostatic pressure against it. Arches may be synonymous with vau ...

ing. A set of interconnected force chains is known as a force network. Force networks visualise inter-particle forces, which is particularly informative for spherical particle systems. For non-spherical particle systems force chain networks benefit from being supplemented by traction chain networks. Traction chains visualise inter-particle tractions, which give additional insight in inter-particle contact not captured by force chains, in particular, the role of contact area over which inter-particle forces act. Force networks are an

emergent phenomenon In philosophy, systems theory, science, and art, emergence occurs when an entity is observed to have properties its parts do not have on their own, properties or behaviors that emerge only when the parts interact in a wider whole. Emergenc ...

that are created by the complex interaction of the individual grains of material and the patterns of pressure applied within the material. Force chains can be shown to have

fractal In mathematics, a fractal is a geometric shape containing detailed structure at arbitrarily small scales, usually having a fractal dimension strictly exceeding the topological dimension. Many fractals appear similar at various scales, as il ...

properties. Force chains have been investigated both experimentally, through the construction of specially instrumented physical models, and through computer simulation.

References

External links

Force Chains and Distributions in Bead Packs
Granularity of materials Emergence Fractals {{fractal-stub