Inhalt

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   Title page
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   Acknowledgment
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   Abstract
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   Kurzzusammenfassung
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   Contents
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   Abbreviations
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   Symbols
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  1 Introduction
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   1.1 Potential of continuous fiber thermoplastic composites
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   1.2 Motivation
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   1.3 Objective
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   1.4 Procedure
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  2 Theoretical background
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   2.1 Fiber composite materials
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   2.1.1 Fibers
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   2.1.2 Matrix
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   2.2 Energy absorption characteristics of fiber composites
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   2.2.1 Flat specimens
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   2.2.2 Self-supporting specimens
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   2.3 Size effect
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   2.4 Lamina stress-strain law
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   2.5 Failure of composite materials
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   2.5.1 Failure surface testing
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   2.5.2 Failure criteria
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   2.6 Explicit finite element method
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   2.7 User-defined material modeling (VUMAT)
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   2.8 Elasto-plasticity
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  3 Experimental material testing
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   3.1 Material
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   3.2 Tensile test
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   3.2.1 Test specimen
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   3.2.2 Test procedure
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   3.2.3 Results
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  3.3 Compression test
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   3.3.1 Test specimen
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   3.3.2 Test procedure
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   3.3.3 Results
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   3.4 Shear test
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   3.4.1 Test results
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   3.4.2 Cyclic shear test
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   3.5 Intra-laminar fracture energy
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   3.5.1 Tensile fracture energy
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   3.5.2 Compression fracture energy
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   3.6 Axial crushing behavior
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  4 Continuum damage mechanics
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   4.1 Basics of CDM
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  4.2 Ls-Dyna CDM model MAT_Laminated_Composite_Fabric
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   4.2.1 Fiber response
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   4.2.2 In-plane shear response
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   4.3 Abaqus CDM model ABQ_PLY_FABRIC
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   4.3.1 Fiber response
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   4.3.2 In-plane shear response
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  4.4 Validation
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   4.4.1 Three-point bending of rectangular specimen
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   4.4.2 U-profile
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   4.5 Conclusion
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   5 Shear modeling
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   5.1 Testing
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   5.1.1 Frame shear test
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   5.1.2 Rail shear test
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   5.1.3 Compression shear
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   5.1.4 Results and comparison
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  5.2 Improved shear modelling
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   5.2.1 Results
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   5.3 Validation
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   5.4 Conclusion
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  6 Strain-rate modelling
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  6.1 Test
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   6.1.1 Tensile strain-rate dependency
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   6.1.2 Shear strain-rate dependency
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  6.2 Strain rate-dependent modeling
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   6.2.1 Strain rate dependency in the fiber direction
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   6.2.2 Strain rate dependency along in-plane shear
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   6.2.3 Implementation as user-defined material subroutine
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   6.3 Validation
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   6.3.1 FEM model setup
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   6.3.2 Results
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   6.3.3 Discussion
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   6.4 Conclusion
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  7 Failure surface
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   7.1 Testing
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   7.2 Conclusion
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  8 Size effect
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   8.1 Size effect in tension
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   8.2 Size effect in bending
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   8.2.1 Pin-end buckling test
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   8.3 Proposed method for scaling strength in user-material subroutine
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   8.4 Conclusion
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  9 Axial crush simulation
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   9.1 Inter-laminar fracture energy measurement
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   9.1.1 DCB test
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   9.1.2 ENF test
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  9.2 Delamination modeling
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   9.2.1 Constitutive model of cohesive elements
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   9.2.2 Parameter calibration
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   9.2.3 Single-element simulation
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   9.2.4 Influence of cohesive modeling on composite response
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  9.3 Validation
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   9.3.1 DCB simulation
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   9.3.2 ENF simulation
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   9.4 Axial crush simulation
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   9.4.1 Conclusion
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  10 Summary and Outlook
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   10.1 Summary
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   10.2 Outlook
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   11 Bibliography
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  12 Annex
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  12.1 Test results data
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   12.1.1 Frame shear
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   12.1.2 Rail shear
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   12.1.3 Compression shear
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   12.1.4 High-speed tensile test
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   12.1.5 High-speed shear test
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   12.1.6 Off-axis tests
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   12.1.7 DCB test
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   12.1.8 ENF test
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  12.2 Specimen photos
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   12.2.1 Tensile test specimens
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   12.2.2 Compression tests specimens
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   12.2.3 Tensile-shear test specimens
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   12.2.4 Intralaminar fracture energy specimens
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   12.2.5 Axial crash of corrugated specimens
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   12.2.6 Rail shear tests specimens
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   12.2.7 Tensile shear specimens
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   12.2.8 Compression shear specimen
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   12.2.9 High speed tensile test specimens
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   12.2.10 High-speed shear specimen
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   12.2.11 Off-axis tensile test specimen
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  12.3 CAD drawings
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   12.3.1 CLC fixture
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   12.3.2 Clevis design for intra-laminar fracture energy
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   12.3.3 Frame shear fixture
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   12.3.4 Rail shear fixture
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   12.3.5 Pin-end buckling fixture