Peridynamic modeling of the crack velocity dependence via an incubation time fracture criterion

TL;DR

This paper models the relationship between crack velocity and stress intensity factor in dynamic fracture mechanics using a peridynamic approach, incorporating an incubation time fracture criterion, and compares results with experimental data.

Contribution

It introduces a peridynamic model with an incubation time fracture criterion to analyze crack velocity effects, revealing new insights into SIF variation and micro-branching.

Findings

Significant variation in SIF at nearly constant crack velocities.

Micro-branching occurs at higher crack velocities, increasing SIF scatter.

Numerical results align with experimental observations.

Abstract

This study investigates one of the central problems of dynamic fracture mechanics, namely the dependence of the instantaneous stress intensity factor (SIF) on the crack propagation velocity. For this purpose, the well-known experiments by Ravi-Chandar and Knauss on brittle, amorphous Homalite-100 polymer plates are modeled using a peridynamic approach. The numerical model integrates the previously proposed remote stress fracture criterion into an incubation time fracture criterion. Results of numerical modeling indicate a significant variation in SIF values at an almost constant crack propagation velocity. Moreover, for higher crack propagation velocities, micro-branching is obtained numerically, leading to a larger scatter of SIF values. These effects were also observed in the experiments of Ravi-Chandar and Knauss, which provides new insights into the nature of the crack-velocity dependence of the Mode-I SIF.