1st Edition

The Behavior of Sandwich Structures of Isotropic and Composite Materials

By Jack R. Vinson Copyright 1999

    The Behavior of Sandwich Structures of Isotropic and Composite Materials presents the mathematics, descriptions, and analytical techniques in the growing field of sandwich structures. From a background in sandwich structures to thermoelastic problems of sandwich structures and sandwich shell theory, the book provides the knowledge needed to analyze, design, and optimize various sandwich structures.

    As one would expect from a book on sandwich structures, this volume discusses special failure modes such as face wrinkling and core shear instability. Coverage includes not only honeycomb cores, but also foam, web, and truss cores. An important topic in composite structure design, optimization is explored in two chapters on sandwich plates and sandwich shells. The author presents the optimization techniques in closed form and the methods are applicable to material selection and geometric design. The book also contains a set of problems and references at the end of each chapter. This text is ideal for engineers-in-training, as well as practical engineers who desire a comprehensive understanding of sandwich structures technology.

    SANDWICH STRUCTURES: ORIGINS, ADVANTAGES, AND USES
    Description of Various Sandwich Constructions
    Advantages of Sandwich Construction over Construction Monocoque Thin Walled Construction
    Origins of Sandwich Construction
    Uses of Sandwich Construction
    Present Approach to Analysis
    Problems
    References

    ANISTROPIC ELASTICITY AND COMPOSITE LAMINATE THEORY
    Introduction
    Derivation of the Anisotropic Elastic Stiffness and Compliance Matrices
    The Physical Meaning of the Components of the Orthotropic Elasticity Tensor
    Methods to Obtain Composite Elastic Properties from Fiber and Matrix Properties
    Thermal and Hygrothermal Considerations
    Time-Temperature Effects on Composite Materials
    High Strain Rate Effects on Material Properties
    Laminae of Composite Materials
    Laminate Analysis
    [A], [B], and [D] Stiffness Matrices for a Mid-Plane Symmetric Sandwich Structure
    Piezoelectric Effects
    Problems
    References

    DERIVATION OF THE GOVERNING EQUATIONS FOR SANDWICH PLATES (PANELS)
    Introduction
    Plate Equilibrium Equations
    The Bending of Composite Material Laminated and/or Sandwich Plates: Classical Theory
    Classical Plate Theory Boundary Conditions
    Analysis of Composite Materials Laminated and/or Sandwich Panels Including Transverse Shear Deformation Effects
    Boundary Conditions for a Plate Using the Refined Plate Theory
    Laminated or Sandwich Plate on an Elastic Foundation
    Laminated or Sandwich Plates Subjected to Dynamic Loads
    Problems
    References

    BEAMS, COLUMNS, AND RODS OF COMPOSITE MATERIALS Development of Classical Beam Theory
    Some Simplified Sandwich-Beam Solutions
    Eigenvalue Problems of Sandwich Beams: Natural Vibrations and Elastic Stability
    Other Considerations
    Problems
    References

    ENERGY METHODS FOR SANDWICH STRUCTURES
    Introduction
    Theorem of Minimum Potential Energy
    Analysis of a Beam in Bending Using the Theorem of Minimum Potential Energy
    Reissner's Variational Theorem and Its Applications
    Static Deformation of Moderately Thick Beams
    Flexural Vibrations of Moderately Thick Beams
    Flexural Natural Frequencies of a Simply Supported Beam Including Transverse Shear Deformation and Rotatory Inertia Effects
    Minimum Potential Energy for Rectangular Plates
    A Rectangular Composite Material Plate Subjected to Lateral and Hygrothermal Loads
    In-Plane Shear Strength Determination of Composite Materials in Laminated and Sandwich Panels
    Problems
    References

    SOLUTIONS FOR RECTANGULAR SANDWICH PLATES
    Introduction
    Navier Solutions for Rectangular Sandwich Plates
    Levy Solutions for Plates of Composite Materials
    Perturbation Solutions for the Bending of a Composite Material Sandwich Plate, with Mid-Plane Symmetry and No Bending-Twisting Coupling
    Isotropic Sandwich Panels Subjected to a Uniform Lateral Load
    Minimum Weight Optimization for a Sandwich Panel Subjected to a Distributed Lateral Load
    Analysis of an Isotropic Sandwich Plate on an Elastic Foundation Subjected to a Uniform Lateral Load
    Static Analysis of Sandwich Plates of Composite Materials Including Transverse Shear Deformation Effects
    Exact Solution
    Other Considerations
    Problems
    References

    DYNAMIC EFFECTS ON SANDWICH PANELS
    Introduction
    Natural Flexural Vibrations of Sandwich Plates: Classical Theory
    Natural Flexural Vibrations of Sandwich Plates Including Transverse Shear Deformation Effects
    Forced-Vibration Response of a Sandwich Plate Subjected to a Dynamic Lateral Load
    Dynamic Response of Sandwich Plates to Localized Loads
    Large Amplitude Nonlinear Oscillations of Sandwich Plates Simply Supported on All Edges
    Linear and Nonlinear Oscillations of Specially Orthotropic Sandwich Panels with Various Boundary Conditions
    Vibration Damping
    Problems
    References

    THERMAL AND MOISTURE EFFECTS ON SANDWICH STRUCTURES
    General Considerations
    Derivation of the Governing Equations for a Thermoplastic Isotropic Plate
    Boundary Conditions
    General Treatment of Plate Nonhomogeneous Boundary Conditions
    Thermoelastic Effects on Beams
    Self-Equilibrium of Thermal Stress
    Rectangular Composite Material Plate Subjected to Lateral and Hygrothermal Loads
    References

    ELASTIC INSTABILITY (BUCKLING) OF SANDWICH PANELS General Considerations
    The Buckling of an Orthotropic Sandwich Plate Subjected to In-Plane Loads Classical Theory
    Elastic Stability of a Composite Sandwich Panel Including Transverse Shear Deformation and Hygrothermal Effects
    The Buckling of an Isotropic Plate on an Elastic Foundation Subjected to Biaxial In-Plane Compressive Loads
    The Buckling of Honeycomb Core Sandwich Panels Subjected to In-Plane Compressive Loads
    The Buckling of Solid- or Foam-Core Sandwich Panels Subjected to In-Plane Compressive Loads
    Buckling of a Truss-Core Sandwich Panel Subjected to Uniaxial Compression
    Elastic Stability of a Web-Core Sandwich Panel Subjected to a Uniaxial Compressive In-Plane Load
    Buckling of Honeycomb-Core Sandwich Panels Subjected to In-Plane Shear Loads
    Buckling of Solid-Core or Foam-Sandwich Panel Subjected to In-Plane Shear Loads
    Buckling of a Truss-Core Sandwich Panel Subjected to In-Plane Shear Loads
    Buckling of a Web-Core Sandwich Panel Subjected to an In-Plane Shear Load
    Other Considerations
    Problems
    References

    STRUCTURAL OPTIMIZATION TO OBTAIN MINIMUM-WEIGHT SANDWICH PANELS
    Introduction
    Minimum Weight Optimization of Honeycomb-Core Sandwich Panels Subjected to a Unidirectional Compressive Load
    Minimum Weight Optimization of Foam-Core Sandwich Panels Subjected to a Unidirectional Compressive Load
    Minimum Weight Optimization of Truss-Core Sandwich Panels Subjected to a Unidirectional Compressive Load
    Minimum Weight Optimization of Web-Core Sandwich Panels Subjected to a Unidirectional Compressive Load
    Minimum Weight Optimization of Honeycomb-Core Sandwich Panels Subjected to In-Plane Shear Loads
    Minimum Weight Optimization of Solid- and Foam-Core Sandwich Panels Subjected to In-Plane Shear Loads
    Minimum Weight Optimization of Truss-Core Sandwich Panels Subjected to In-Plane Shear Loads
    Minimum Weight Optimization of Web-Core Sandwich Panels Subjected to In-Plane Shear Loads
    Optimal Stacking Sequences for Composite Material Laminate Faces for Various Sandwich Panels Subjected to Various Loads
    Problems
    References

    SANDWICH SHELLS
    Introduction
    Analysis of Sandwich Cylindrical Shells under Axially Symmetric Loads
    A General Solution for Orthotropic-Sandwich Cylindrical Shells under Axially Symmetric Loads
    Shells with Mid-Plane Asymmetry
    Other Considerations
    Problems
    References

    BUCKLING OF SANDWICH CYLINDRICAL SHELLS
    Buckling of a Solid- or Foam-Core Sandwich Cylindrical Shell with Isotropic Faces Subjected to an Axially Symmetric Compressive End Load
    Buckling of a Solid- or Foam-Core Sandwich Cylindrical Shell with Orthotropic Composite Faces Subjected to an Axially Symmetric Compressive Load
    Buckling of a Honeycomb-Core Sandwich Cylindrical Shell with Composite Faces Subjected to an Axially Symmetric Compressive End Load
    Overall Buckling of Sandwich Cylindrical Shells Subjected to an Overall Bending Moment
    Buckling of a Sandwich Cylindrical Shell Due to External Pressure
    Buckling of a Sandwich Cylindrical Shell Due to Torsion
    Dynamic Buckling
    Problems
    References

    MINIMUM WEIGHT OPTIMIZATION OF SANDWICH CYLINDRICAL SHELLS
    General Discussion
    Minimum Weight Optimization of a Solid Foam-Core Sandwich Cylindrical Shell with Isotropic Faces Subjected to an Axially Compressive Load
    Minimum Weight Optimization of a Solid- or Foam-Core Sandwich Cylindrical Shell with Orthotropic Composite Material Faces Subjected to an Axially Compressive Load
    Minimum Weight Optimization of a Honeycomb-Core Sandwich Cylindrical Shell with Composite Material Faces Subjected to an Axially Symmetric Compressive Load
    Problems
    References

    APPENDIX 1: Core Materials
    APPENDIX 2: Face Materials
    APPENDIX 3: American Society for Testing Materials (ASTM) Standards for Sandwich Structures and Materials

    INDEX

    Biography

    Vinson, JackR.

    "Most composite textbooks focus on basic laminate theory. This is an important subject, but it will only get you so far. At some point, you will need to move beyond simple point stress analysis and start looking at complex structures.
    One of Jack Vinson's earlier books, The Behavior of Structures Composed of Composite Materials, has long been on my list of essential references. It starts with a brief review of lamination theory, then gets right into the analysis of beams, plates, and shells. It is a graduate level textbook, but could be targeted to advanced seniors.
    The Behavior of Sandwich Structures picks up where The Behavior of Structures leaves off. It essentially covers the same types of structures, but at a more advanced level. It also covers some new subject areas like structural optimization.
    Any sandwich structure, whether it has isotropic or anisitropic facesheets, can be treated as a composite. Traditional composite theories can be used, with the important addition of transverse shear effects.
    Governing differential equations are given for beams, plates, and shells. Several solution methods are outlined, including both direct solutions and energy methods. Solutions for some specific geometries and boundary conditions are worked out in full, but most are left as an excercise (this is a textbook, after all). Governing equations and solutions cover static and dynamic loads, thermal and moisture effects, and eigenvalues (natural frequencies and stability).
    As one would expect from a book on sandwich structures, special failure modes such as face wrinkling and core shear instability are discussed. Core materials aren't limited to honeycomb, but also include foam-cores, web-cores, and truss-cores.
    One of the more important topics in composite structure design is optimization, and Dr. Vinson provides two chapters on the subject: one for sandwich plates; and one for sandwich shells. The optimization techniques are all closed form, so you won't see much on layup optimization, but the methods are applicable to material selection and geometric design. After working through some optimization solutions, some general design guidelines become apparent.
    Aside from the primary technical content, Sandwich Structures contains a list of homework problems (again, it's meant to be a textbook) and references at the end of each chapter. Many of the references are to other works by Dr. Vinson, but that just shows he is the right person to author this book.
    If you've read any of my earlier reviews, you know that I'm quite picky when it comes to typography and grammar. In that sense, this book was a pleasant change: I found only a few typos in equations, and even fewer obvious grammatical errors. … the binding is of good quality.
    Even if you aren't designing sandwich structures, you will still find this book useful. Because sandwiches are treated like composites, the theories and solutions can be applied to monocoque structures. And if you are designing sandwich structures, then this book will make your job a lot easier."
    -About.com book review