Table Of ContentMECHANICS OF FIBROUS COMPOSITES
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British Library Cataloguing in Publication Data
Datoo, Mahmood Husein
Mechanics of fibrous composites.
1. Composite Materials I.
Title
620.118
ISBN 1-85166-600-1
Library of Congress Cataloging-in-Publication Data
Datoo, Mahmood Husein.
Mechanics of fibrous composites/Mahmood Husein Datoo.
p. cm.
Includes bibliographical references and index.
ISBN 1-85166-600-1
1. Fiber reinforced plastics. I. Title.
TA455.P55D27 1991
620.1'923-dc20 91-2204
CIP
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Preface
Contents
Preface ............................................................................................................vii
1 Introduction ..................................................................................................1
1.1 Fibrous Composites ........................................................................................................1
1.2 FRP Constituents ............................................................................................................2
1.3 Reinforcement Types ......................................................................................................6
1.4 Types of Materials ..........................................................................................................9
1.5 Terminology .................................................................................................................11
2 Ply Stiffness Analysis .................................................................................14
2.1 Isotropic Ply ..................................................................................................................16
2.2 Specially Orthotropic Ply ..............................................................................................24
2.3 Generally Orthotropic Ply .............................................................................................34
2.4 Transformation of Elastic Constants .............................................................................45
2.5 Typical Elastic Properties .............................................................................................66
3 Ply Strength Analysis ...................................................................................68
3.1 Isotropic Ply ..................................................................................................................68
3.2 Orthotropic Ply .............................................................................................................74
3.3 Failure Criteria ..............................................................................................................75
3.4 Sign of Shear Stresses ...................................................................................................92
3.5 Choice of Failure Criterion ...........................................................................................96
3.6 Typical Strength Properties ...........................................................................................97
4 Layered Laminate ......................................................................................99
4.1 Beam Constitutive Equation .........................................................................................99
4.2 Laminate Constitutive Equation ..................................................................................113
4.3 Laminate Notation ......................................................................................................129
4.4 Equivalent Elastic Constants .......................................................................................136
xi
xii Contents
5 Laminate Stiffness Analysis ...................................................................149
5.1 Stiffness Formulation Procedure ....................................................149
5.2 Laminate Configuration Types ......................................................153
5.3 Symmetric SOPL: Isotropic Plies ..................................................155
5.4 Symmetric SOPL: Specially Orthotropic Plies ..............................163
5.5 Symmetric SOPL: Generally Orthotropic Plies .............................170
5.6 Symmetric MOPL: Isotropic Plies .................................................177
5.7 Symmetric MOPL: Generally Orthotropic Plies ...........................185
5.8 Symmetric MOPL: Cross-ply .........................................................191
5.9 Symmetric MOPL: Angle-ply ........................................................201
5.10 Symmetric MOPL: Quasi-isotropic .............................................216
5.11 Antisymmetric MOPL: Cross-ply ................................................225
5.12 Antisymmetric MOPL: Angle-ply ...............................................231
5.13 Estimated Membrane Elastic Constants .......................................236
5.14 Laminate Stiffness: Summary ......................................................245
6 Laminate Strength Analysis ..................................................................248
6.1 First-Ply-Failure (FPF) Procedure .................................................248
6.2 FPF: Symmetric Laminate—Membrane Load ...............................253
6.3 FPF: Symmetric Laminate—Bending Load ..................................260
6.4 FPF: Unsymmetric Laminate—Membrane Load ..........................265
6.5 Last-Ply-Failure (LPF) Procedure ..................................................269
6.6 LPF: Complete Ply Failure—Membrane Load ..............................273
6.7 LPF: Partial Ply Failure—Membrane Load ...................................302
6.8 LPF: Complete Ply Failure—Bending Load ..................................333
6.9 Estimated Laminate Strength .........................................................355
6.10 Laminate Strength: Summary .......................................................364
7 Residual Stresses ......................................................................................367
7.1 Compound Isotropic Beam .............................................................367
7.2 Laminate Thermal Stresses ............................................................374
7.3 Determining Thermal Residual Stresses ........................................389
7.4 Constant Temperature Distribution ................................................391
7.5 Hygroscopic Diffusion Mechanism ...............................................422
7.6 Laminate Hygroscopic Stresses .....................................................426
7.7 Constant and Linear Moisture Distribution ...................................431
7.8 Influence on Laminate Strength .....................................................471
7.9 Typical Physical Properties ............................................................482
8 Thin-Walled Composite Sections ...........................................................483
8.1 Assumptions and Axes Systems .....................................................484
8.2 Axial Force .....................................................................................485
8.3 Symmetrical Bending .....................................................................497
8.4 Unsymmetrical Bending .................................................................508
8.5 Shear Forces ...................................................................................517
