# Shear jamming and fragility in dense suspensions

## TL;DR

This paper investigates shear jamming in dense suspensions, revealing that shear-induced jammed states are fragile and depend on flow history, with simulations showing distinct microstructural signatures.

## Contribution

It provides the first detailed simulation-based analysis of fragile shear-jammed states and their microstructural characteristics in dense suspensions.

## Key findings

- Shear-jammed states are fragile and unstable under incompatible stresses.
- Flow-induced microstructures determine the stress response.
- Simulations distinguish shear-jammed states from isotropic jammed states.

## Abstract

The phenomenon of shear-induced jamming is a factor in the complex rheological behavior of dense suspensions. Such shear-jammed states are fragile, i.e., they are not stable against applied stresses that are incompatible with the stress imposed to create them. This peculiar flow-history dependence of the stress response is due to flow-induced microstructures. To examine jammed states realized under constant shear stress, we perform dynamic simulations of non-Brownian particles with frictional contact forces and hydrodynamic lubrication forces. We find clear signatures that distinguish these fragile states from the more conventional isotropic jammed states.