Journal article

Self-assembly in a near-frictionless granular material: conformational structures and transitions in uniaxial cyclic compression of hydrogel spheres

David M Walker, Antoinette Tordesillas, Nicolas Brodu, Joshua A Dijksman, Robert P Behringer, Gary Froyland



We use a Markov transition matrix-based analysis to explore the structures and structural transitions in a three-dimensional assembly of hydrogel spheres under cyclic uniaxial compression. We apply these methods on experimental data obtained from a packing of nearly frictionless hydrogel balls. This allows an exploration of the emergence and evolution of mesoscale internal structures - a key micromechanical property that governs self-assembly and self-organization in dense granular media. To probe the mesoscopic force network structure, we consider two structural state spaces: (i) a particle and its contacting neighbours, and (ii) a particle's local minimal cycle topology summarized by a cyc..

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Awarded by US Army Research Office

Awarded by Australian Research Council Discovery Projects

Awarded by Future Fellowship

Awarded by NASA

Awarded by NSF

Awarded by Division Of Materials Research

Funding Acknowledgements

We thank the anonymous reviewers for useful suggestions which helped improved the quality of the paper. This work was supported by US Army Research Office (W911NF-11-1-0175, W911NF-1-11-0110), the Australian Research Council Discovery Projects 2012 (DP120104759) and a Future Fellowship (FT120100025), NASA grant (NNX10AU01G), NSF grant (DMR12-06351), the W. M. Keck Foundation and the Melbourne Energy Institute.