High-fidelity damage modelling of CFRP laminates for impact and crashworthiness applications – dynamic tube crushing simulations

D E Sommer,H Cui,O Falcó,G Quino,D Thomson,N Petrinic,F Gálvez Díaz-Rubio,D.A Cendón Franco

doi:10.1051/epjconf/202125002014

Abstract

Drop weight impact experiments were conducted on angle-ply carbon fibre reinforced polymer (CFRP) composite crush tubes. The dynamic response was modelled using explicit finite element methods and continuum damage mechanics and cohesive zone modelling in both Abaqus/Explicit and LS-DYNA. User-defined constitutive models for the intra-ply behaviour were used and a fibre-aligned meshing technique was implemented. The results of the experiments and simulations are compared to evaluate accuracy of the different modelling techniques, highlighting the advantages and drawbacks of each approach. Among these, the choice of meshing strategy is shown to be especially important in capturing the physical propagation of cracks and damage mechanisms in CFRP laminates.

Highlights

For the finite element analysis of composite laminates under high energy dynamic loading, where significant damage may be expected, an accurate prediction of the damage modes such as transverse matrix cracks, axial splits, fibre kinking, crushing and delamination can be just as important as the prediction of the dissipated energy
The choice of meshing strategy is shown to be especially important in capturing the physical propagation of cracks and damage mechanisms in carbon fibre reinforced polymer (CFRP) laminates
The use of unaligned meshes, even when paired with advanced 3D damage models, has shown limited ability to describe the propagation of matrix cracks through the material, which can severely affect the accuracy of the model beyond the initial onset of damage

Summary

Introduction

For the finite element analysis of composite laminates under high energy dynamic loading, where significant damage may be expected, an accurate prediction of the damage modes such as transverse matrix cracks, axial splits (fibre/matrix shearing), fibre kinking, crushing and delamination can be just as important as the prediction of the dissipated energy. In terms of energy absorbtion, CFRP are presented as a good candidate owing to their enhanced capability with high specific strength, stiffness and fracture toughness. The competition between the different energy-dissipating damage modes on composite, present a difficult challenge for accurate predictions of both strength and failure mechanisms. The use of unaligned meshes, even when paired with advanced 3D damage models, has shown limited ability to describe the propagation of matrix cracks through the material, which can severely affect the accuracy of the model beyond the initial onset of damage. Previous numerical modelling work on the crushing of CFRP tubes has shown that even coarse, unaligned meshes can produce reasonable results in terms of the overall force-

Methods

Results

Conclusion