An efficient hierarchical modeling framework for predicting the low velocity impact response of 3D braided composites

Abstract Three‐dimensional (3D) braided composite materials have great advantages in improving the damage tolerance of aeronautical structures. However, the complex meso‐structure has always made it a challenge to predict anti‐impact behaviors. To tackle this issue, the present work provides an efficient hierarchical modeling framework regarding the low velocity impact (LVI) modeling of 3D braided composites. In the present framework, the mechanical properties of fiber bundles are predicted using micromechanics theory. Two sets of mesoscale representative volume elements (RVEs) are constructed based on the actual braided architecture: the inner RVE and the surface RVE. Meso‐scale analysis was verified through comparison with the coupon level test, demonstrating the difference in mechanical behaviors between the two RVEs, both of which were taken into consideration in the macro‐scale FEM analysis. The results demonstrate that the predicted LVI mechanical responses and damage patterns fit well with the experimental results of 3D braided composites, with a deviation of less than 10% on the impact duration time, maximum contact force, and deflection. This study provides insights into understanding the LVI failure mechanism of 3D braided composites, and guidance for designing and optimizing 3D braided composite structures.