# Mean-field scenario for the athermal creep dynamics of yield-stress fluids

## TL;DR

This paper presents a mean-field elasto-plastic model for athermal yield-stress fluids that captures their transient creep dynamics, including re-acceleration and fluidization phases, with results depending on initial conditions.

## Contribution

It introduces a novel mean-field framework that reproduces experimental creep behaviors and elucidates the physical processes during fluidization in yield-stress materials.

## Key findings

- Reproduces non-linear shear-rate response to shear-stress.
- Identifies distinct re-acceleration and fluidization phases.
- Fluidization time depends on initial conditions and static yield stress.

## Abstract

We develop an elasto-plastic description for the transient dynamics prior to steady flow of athermally yielding materials. Our mean-field model not only reproduces the experimentally observed non-linear time dependence of the shear-rate response to an external shear-stress, but also allows for the determination of the different physical processes involved in the onset of the re-acceleration phase after the initial critical slowing down and a distinct well defined fluidization phase. The evidenced power-law dependence of the fluidization time on the distance of the applied to an age dependent static yield stress is not universal but strongly dependent on initial conditions.