Abstract:To improve the analysis of fatigue multi-crack propagation problem, a method for fatigue multi-crack propagation simulation based on ordinary state-based peridynamics was established. Based on ordinary state-based peridynamics theory, a plane stress peridynamics model for fatigue crack initiation and propagation was proposed by using peridynamics fatigue theory. Due to the large amount of calculation for the peridynamics fatigue model, a parameter named “critical broken bonds number” was introduced to the model to speed up computation. The balance between computational efficiency and suitable crack path accuracy was studied with different “critical broken bonds number” based on an edge-cracked panel. Results show that the calculation was speeded up when an appropriate broken bond number was used, and the crack extention road also kept a precise shape. The fatigue crack of panel with multiple cracks was simulated by the peridynamics fatigue model with different “critical broken bonds number”, and the fatigue crack paths and a-N curve agreed well with the experimental result. Results show that fatigue crack can propagate arbitrarily by the suggested peridynamics fatigue model without setting extra crack extension criteria or preset crack routes, and it significantly improves fatigue multi-crack propagation simulation.