Inversion of force lines in fiber-reinforced jammed granular material
Pavel S Iliev1, Falk K Wittel2, Hans J Herrmann3,4
1ETH Zurich, Computational Physics for Engineering Materials, Institute for Building Materials, Stefano-Franscini-Platz 3, 8093, Zurich, Switzerland.
The European Physical Journal. E, Soft Matter
|April 24, 2021
Summary
Freestanding gravel columns with string reinforcement exhibit surprising stability and load-bearing capacity. Dynamic simulations reveal unique particle networks and forces distinct from silo confinement.
Area of Science:
- Physics
- Materials Science
- Engineering
Background:
- Freestanding columns constructed from loose granular materials like gravel, reinforced with continuous strings, demonstrate remarkable structural integrity.
- These columns can achieve significant heights and withstand substantial vertical loads, capable of causing fragmentation within the granular core.
Purpose of the Study:
- To investigate the underlying mechanisms responsible for the unexpected stability of gravel-string columns.
- To elucidate the structural and force dynamics governing these freestanding granular structures.
Main Methods:
- Dynamic simulations were employed using polyhedral rigid particles to model the gravel.
- Elastic wire chains were incorporated to represent the string reinforcement.
- Analysis focused on the particle contact network, confining forces, and their interplay.
Main Results:
- The simulations revealed a unique fine structure within the particle contact networks of these columns.
- Distinct confining forces were identified, differing fundamentally from those observed in confined granular systems like silos.
- The study quantifies the load-bearing capacity and stability factors.
Conclusions:
- The inherent stability of gravel-string columns arises from specific particle network configurations and force distributions.
- These freestanding granular structures exhibit behaviors distinct from conventionally confined granular materials.
- The findings offer new insights into granular mechanics and structural design.
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