Mode I fracture of a biopolymer gel: rate-dependent dissipation and large deformations disentangled

TL;DR

This study introduces a novel experimental setup to analyze fracture behavior in soft biopolymer gels, revealing how high crack velocities lead to extensive high-strain zones and enabling predictions of energy release rate evolution.

Contribution

The paper presents a new experimental method to investigate soft material fracture at small scales and derives a model predicting energy release rate changes with crack velocity.

Findings

High crack velocities cause large high-strain zones near the crack tip.

Energy dissipation is dominated by viscoelastic processes at high velocities.

The derived prediction matches experimental observations of energy release rate evolution.

Abstract

We have designed a new experimental setup able to investigate fracture of soft materials at small scales. At high crack velocity, where energy is mostly dissipated through viscoelastic processes, we observe an increasingly large high strain domain in the crack tip vicinity. Taking advantage of our ability to determine where linear elasticity breaks down, we derive a simple prediction for the evolution of the energy release rate with the crack velocity.