Application of Building Block Approach on Crashworthiness Design of Composite Vehicular Structures

Abstract

Firstly, the representative volume element (RVE) model was established at the microscale, a three-dimensional micromechanical material constitutive relationship was defined as the user defined material subroutine (UMAT) in ABAQUS/Standard, which was able to accurately capture mechanical behaviors of both matrix and fiber materials. Constrained by periodic boundary conditions (PBCs), the RVE model can be used to predict elastic properties as well as strength properties of the composite laminates. Then, the accuracy of the RVE model was validated by comparing the tensile responses between predictions and experiments. Next, comparisons in the flexural responses of carbon fiber reinforced plastic (CFRP) laminates, lateral and axial crushing behaviors of CFRP tubes between single-layer and multi-layer modeling approaches were investigated at the mesoscale, respectively. Numerical results indicated that the single-layer model was efficient to predict the mechanical indictors while the multi-layer method can reliably predict both mechanical indictors and deformation patterns. Finally, the validated finite element model (FEM) and material constitutive model were employed to investigate the material cost and crashworthiness characteristics of the composite bumper subsystem of the electric vehicle under the frontal crash condition at the macroscale.