Computational Methods for Debonding in Composites

Contents
1 Computational Methods for Debonding in Composites ............ 1
RenédeBorstandJorisJ.C.Remmers
1.1 Introduction . . ............................................ 1
1.2 LevelsofObservation...................................... 3
1.3 Zero-ThicknessInterfaceElements .......................... 5
1.4 Solid-LikeShellFormulation ............................... 12
1.5 The Partition-of-Unity Concept .............................. 15
1.6 DelaminationinaSolid-LikeShellElement................... 21
1.7 ConcludingRemarks ...................................... 23
References..................................................... 24
2 Material and Failure Models for Textile Composites .............. 27
Raimund Rolfes, Gerald Ernst, Matthias Vogler, and Christian Hühne
2.1 Introduction . . ............................................ 28
2.2 Multiscale Analysis ....................................... 29
2.2.1 Homogenization .................................. 31
2.2.2 VoxelMesh ...................................... 32
2.2.3 MicromechanicalUnitCell ......................... 33
2.2.4 MesomechanicalUnitCell.......................... 34
2.3 MaterialModels .......................................... 37
2.3.1 Isotropic Elastic-Plastic Material Model
for Epoxy Resin ................................... 37
2.3.2 Transversely Isotropic Elastic-Plastic Material Model
for Fiber Bundles ................................. 44
2.3.3 TransverselyIsotropicDamageFormulation........... 50
2.4 ResultsofMicromechanicalUnitCellComputations............ 51
2.4.1 ComparisonwithTestResultsfromWWFE ........... 52
2.4.2 Results of Micromechanical Unit Cell
forHomogenization ............................... 54
2.5 Conclusion............................................... 55
References..................................................... 55
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