# 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…

## 2 Citations

### Emerging contact force heterogeneity in ordered soft granular media

- PhysicsMechanics of Materials
- 2021

### Experimental observations of marginal criticality in granular materials

- Materials ScienceProceedings of the National Academy of Sciences of the United States of America
- 2022

Significance Amorphous materials, such as grains, foams, colloids, and glasses, are ubiquitous in nature and our daily life. They can undergo glass transitions or jamming transitions to obtain…

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