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

• A peridynamic framework combined with an incubation time fracture criterion is developed to model dynamic crack propagation in brittle materials. • The model reproduces the experimentally observed trends in the relationship between instantaneous stress intensity factor and crack propagation velocity. • The stress intensity factor exhibits a transient increase and approaches an approximately constant level once the crack velocity stabilizes. • Microbranching emerges naturally at higher crack velocities, while the stress intensity factor shows an extended range associated with crack growth. • Dynamic crack propagation is influenced by incubation time effects. 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 (ITFC). Results of numerical modeling indicate that ITFC model reproduces the trend between stress intensity factor and crack propagation velocity observed in the experiments conducted by Ravi-Chandar and Knauss. Moreover, for higher crack propagation velocities, micro-branching is obtained numerically. These results provide new insights into the nature of the crack-velocity dependence of the Mode-I SIF.