Mechanics of Aeronautical Composite Materials

Description

This book presents the principles of composite laminate sizing widely used for composite structures. The focus is on aeronautics in particular, including the concepts of limit loads and ultimate loads. After a brief overview of the main composite materials used in aeronautics, the basic theory of laminated plates and the associated rupture criteria are given. The author presents two fundamental cases of the sizing of aeronautical composite structures: the calculation of the holed structures and their subsequent multi-bolt joints, and the calculation of the buckling. The concept of damage tolerance is also explored, with a focus on its application for tolerance to impact damage. These notions are fundamental for understanding the specificities of the sizing of aeronautical composite structures. The book also contains corrected exercises for the reader to test their understanding of the different topics covered.;Cover; Half-Title Page; Title Page; Copyright Page; Contents; Foreword; Preface; Introduction; 1. Presentation of an Aeronautical Unidirectional Composite; 1.1. Introduction; 1.2. Carbon/epoxy composite T300/914; 1.3. Polymers; 2. Characteristics of UD Ply; 2.1. State of stress of UD ply; 2.2. Tensile test in the l-direction; 2.3. Tensile test along the t-direction; 2.4. Shear test; 2.5. General case; 3. Characteristics of a UD Ply in a Given Direction; 3.1. Off-axis tensile test; 4. Fracture of a Laminated Composite; 4.1. Fracture of a UD ply; 4.1.1. Longitudinal tension. Cover Half-Title Page Title Page Copyright Page Contents Foreword Preface Introduction 1. Presentation of an Aeronautical Unidirectional Composite 1.1. Introduction 1.2. Carbon/epoxy composite T300/914 1.3. Polymers 2. Characteristics of UD Ply 2.1. State of stress of UD ply 2.2. Tensile test in the l-direction 2.3. Tensile test along the t-direction 2.4. Shear test 2.5. General case 3. Characteristics of a UD Ply in a Given Direction 3.1. Off-axis tensile test 4. Fracture of a Laminated Composite 4.1. Fracture of a UD ply 4.1.1. Longitudinal tension. 4.1.2. Longitudinal compression4.1.3. Transverse tension 4.1.4. Transverse compression 4.1.5. In-plane shear 4.2. Fracture of a laminate 5. Fracture Criteria of a UD Ply 5.1. Maximum stress fracture criterion 5.2. Maximum strain fracture criterion 5.3. Hill's criterion 5.4. Tsai-Wu criterion 5.5. Yamada-Sun criterion 5.6. Conclusion 6. Membrane Behavior of a Laminated Composite Plate 6.1. Generalities and notations 6.2. Membrane behavior, bending behavior and mirror symmetry 6.3. Resultant forces 6.4. Displacement field, stress field and strain field. 6.5. Tension / shear coupling7. Bending Behavior of a Laminated Composite Plate 7.1. Notations 7.2. Resultant moments 7.3. Displacement field, stress field and strain field 7.4. Bending/twisting coupling 8. The Fracture Criterion of a Laminate 8.1. The sizing criterion 8.2. Test on a composite structure 8.3. Sizing principle 8.4. Sizing a given structure for a given loading 8.5. Optimal structure for a given load 9. Damage Tolerance 9.1. The principle of damage tolerance 9.2. Damage during impact and compression after impact 9.3. Sizing for impact damage tolerance. 10. Interlaminar and Out-of-Plane Shear Stress10.1. Tension of a cross-ply laminate [0,90]S 10.2. Tension of a cross-ply laminate [45,-45]S 10.3. Out-of-plane shear stress 11. Holed and Bolted Plates 11.1. Calculating holed composite plates 11.2. Calculating the multi-bolt composite joints 12. Buckling 12.1. Reminder surrounding beam buckling 12.2. Buckling of plates under compression 12.3. Plate buckling under shear loading 13. Miscellaneous Rules for Stacking 14. Exercises 14.1. Experimental determination of the characteristics of a UD material 14.2. Fracture of a laminate. 14.3. Shear modulus14.4. Optimization of stacking sequence 14.5. Composite tube 14.6. Laminate calculation without calculation 14.7. Sandwich beam under bending 14.8. Laminate plate under compression 14.9. Tube under torsion/internal pressure 14.10. Optimization of a fabric with a strain fracture criterion 14.10.1. Part 1: preamble 14.10.2. Part 2: quasi-isotropic stacking sequence 14.10.3. Part 3: stacking sequence optimization 14.10.4. Part 4: stacking sequence optimization under bending 14.11. Open hole tensile test 14.12. Multi-bolt composite joint.