Contact force measurements and local anisotropy in ellipses and disks

@inproceedings{Wang2021ContactFM,
  title={Contact force measurements and local anisotropy in ellipses and disks},
  author={Yinqiao Wang and Jin Shang and Yujie Wang and J. Zhang},
  year={2021}
}
Experimental measurements of contact forces are limited to spheres and disks in three and two dimensions, making the evaluation of shape effect and universality of force distributions and comparison between experiments and theories extremely difficult. Here we present precise measurements of vector contact forces in photoelastic ellipses and disks subject to isotropic compression and pure shear. We find the local, instead of the global, stress ratio controls the width of force distributions for… 

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