Stress-stress Correlations Reveal Force Chains in Gels

Abstract

We investigate the spatial correlations of microscopic stresses in soft particulate gels, using 2D and 3D numerical simulations. We use a recently developed theoretical framework predicting the analytical form of stress-stress correlations in amorphous assemblies of athermal grains that acquire rigidity under an external load. These correlations exhibit a pinch-point singularity in Fourier space leading to long-range correlations and strong anisotropy in real space, which are at the origin of force-chains in granular solids. Our analysis for the model particulate gels at low particle volume fractions demonstrates that stress-stress correlations in these soft materials have characteristics very similar to those in granular solids and can be used to identify force chains. We show that the stress-stress correlations can distinguish floppy from rigid gel networks and the intensity patterns reflect changes in shear moduli and network topology, due to the emergence of rigid structures during solidification.

11 pages, 9 figures

References in corpus (6)

• Stress localization, stiffening and yielding in a model colloidal gel
• Self-assembly and cooperative dynamics of a model colloidal gel network
• Tensor Electromagnetism and Emergent Elasticity in Jammed Solids
• Direct Imaging of Contacts and Forces in Colloidal Gels
• Microscopic interactions and emerging elasticity in model soft particulate gels
• Relating Microstructure and Particle-level Stress in Colloidal Crystals Under Increased Confinement

Cited by in corpus (7)

• Schramm-Loewner evolution in 2d rigidity percolation
• Evidences of conformal invariance in 2d rigidity percolation
• Multiscale stress dynamics in sheared liquid foams revealed by tomo-rheoscopy
• Comparative Analysis of Fluctuations in Viscoelastic Stress: A Comparison of the Temporary Network and Dumbbell models
• Long-Range Correlations in Elastic Moduli and Local Stresses at the Unjamming Transition
• Stress-stress correlations in two-dimensional amorphous and crystalline solids
• A Mechanistic Model of the Organization of Cell Shapes in Epithelial Tissues