3rd Edition

Vibrations of Shells and Plates

By Werner Soedel Copyright 2004

    With increasingly sophisticated structures involved in modern engineering, knowledge of the complex vibration behavior of plates, shells, curved membranes, rings, and other complex structures is essential for today’s engineering students, since the behavior is fundamentally different than that of simple structures such as rods and beams. Now in its third edition, Vibrations of Shells and Plates continues to lay an analytical and computational foundation for the study of vibration in these structures.

    Vibrations of Shells and Plates, Third Edition is updated with substantial new material reflecting advances made over the past decade since publication of the second edition. The author demonstrates how the vibration behavior of shells and plates differs from that of beams through theoretical development and examples. He also explains complicating effects on vibration such as the influence of rotation, shear, rotatory inertia, moment loading, residual stresses, and composite layers. New material includes the parabolic cylindrical shell, natural frequencies and modes, power series method, and explicit strain energy equations for many standard cases.

    Intended for graduate and post-graduate study in vibration, acoustics, noise control, and stress analysis, this textbook provides a strong foundation in vibration theory, offers analytical solutions that illustrate actual behavior of structures, and prepares students to perform finite element and finite difference analysis.

    Preface to the Third Edition
    Preface to the Second Edition
    Preface to the First Edition
    Historical Development of Vibration Analysis of Continuous Structural Elements
    References
    Deep Shell Equations
    Shell Coordinates and Infinitesimal Distances in Shell Layers
    Stress-Strain Relationships
    Strain-Displacement Relationships
    Love Simplifications
    Membrane Forces and Bending Moments
    Energy Expressions
    Love’s Equations by Way of Hamilton’s Principle
    Boundary Conditions
    Hamilton’s Principle
    Other Deep Shell Theories
    Shells of Nonuniform Thickness References
    Radii of Curvature
    References
    Equations of Motion for Commonly Occurring Geometries
    Shells of Revolution
    Circular Conical Shell
    Circular Cylindrical Shell
    Spherical Shell
    Other Geometries
    References
    Nonshell Structures
    Arch
    Beam and Rod
    Circular Ring
    Plate
    Torsional Vibration of Circular Cylindrical Shell and Reduction to a Torsion Bar
    References
    Natural Frequencies and Modes
    General Approach
    Transversely Vibrating Beams
    Circular Ring
    Rectangular Plates That are Simply Supported Along Two Opposing Edges
    Circular Cylindrical Shell Simply Supported
    Circular Plates Vibrating Transversely
    Examples: Plate Clamped at Boundary
    Orthogonality Property of Natural Modes
    Superposition Modes
    Orthogonal Modes from Nonorthogonal Superposition Modes
    Distortion of Experimental Modes Because of Damping
    Separating Time Formally
    Uncoupling of Equations of Motion
    In-Plane Vibrations of Rectangular Plates
    In-Plane Vibration of Circular Plates
    Deep Circular Cylindrical Panel Simply Supported at All Edges
    Natural Mode Solutions by Power Series
    On Regularities Concerning Nodelines
    References
    Simplified Shell Equations
    Membrane Approximations
    Axisymmetric Eigenvalues of a Spherical Shell
    Bending Approximation
    Circular Cylindrical Shell
    Zero In-Plane Deflection Approximation
    Example: Curved Fan Blade
    Donnell-Mushtari-Vlasov Equations
    Natural Frequencies and Modes
    Circular Cylindrical Shell
    Circular Duct Clamped at Both Ends
    Vibrations of a Freestanding Smokestack
    Special Cases of the Simply Supported Closed Shell and Curved Panel
    Barrel-Shaped Shell
    Spherical Cap
    Inextensional Approximation: Ring
    Toroidal Shell
    The Barrel-Shaped Shell Using Modified Love Equations
    Doubly Curved Rectangular Plate
    References
    Approximate Solution Techniques
    Approximate Solutions by Way of the Variational Integral
    Use of Beam Functions
    Galerkin’s Method Applied to Shell Equations
    Rayleigh-Ritz Method
    Southwell’s Principle
    Dunkerley’s Principle
    Strain Energy Expressions
    References
    Forced Vibrations of Shells by Modal Expansion
    Model Participation Factor
    Initial Conditions
    Solution of the Modal Participation Factor Equation
    Reduced Systems
    Steady-State Harmonic Response
    Step and Impulse Response
    Influence of Load Distribution
    Point Loads
    Line Loads
    Point Impact
    Impulsive Forces and Point Forces Described by Dirac Delta Functions
    Definitions and Integration Property of the Dirac Delta Function
    Selection of Mode Phase Angles for Shells of Revolution
    Steady-State Circular Cylindrical Shell Response to Harmonic Point Load with All Mode Components Considered
    Initial Velocity Excitation of a Simply Supported Cylindrical Shell
    Static Deflections
    Rectangular Plate Response to Initial Displacement Caused by Static Sag
    The Concept of Modal Mass, Stiffness Damping, and Forcing
    Steady State Response of Shells to Periodic Forcing
    Plate Response to a Periodic Square Wave Forcing
    Beating Response to Steady State Harmonic Forcing
    References
    Dynamic Influence (Green’s) Function
    Formulation of the Influence Function
    Solution to General Forcing Using the Dynamic Influence Function
    Reduced Systems
    Dynamic Influence Function for the Simply Supported Shell
    Dynamic Influence Function for the Closed Circular Ring
    Traveling Point Load on a Simply Supported Cylindrical Shell
    Point Load Traveling Around a Closed Circular Cylindrical Shell in Circumferential Direction
    Steady-State Harmonic Green’s Function
    Rectangular Plate Examples
    Floating Ring Impacted by a Point Mass
    References
    Moment Loading
    Formulation of Shell Equations That Include Moment Loading
    Modal Expansion Solution
    Rotating Point Moment on a Plate
    Rotating Point Moment on a Shell
    Rectangular Plate Excited by a Line Moment
    Response of a Ring on an Elastic Foundation to a Harmonic Point Moment
    Moment Green’s Function
    References
    Vibration of Shells and Membranes Under the Influence of Initial Stresses
    Strain-Displacement Relationships
    Equations of Motion
    Pure Membranes
    Example: The Circular Membrane
    Spinning Saw Blade
    Donnell-Mushtari-Vlasov Equations Extended to Include Initial Stresses
    References
    Shell Equations with Shear Deformation and Rotary Inertia
    Equations of Motion
    Beams with Shear Deflection and Rotary Inertia
    Plates with Transverse Shear Deflection and Rotary Inertia
    Circular Cylindrical Shells with Transverse Shear Deflection and Rotary Inertia
    References
    Combinations of Structures
    Receptance Method
    Mass Attached to Cylindrical Panel
    Spring Attached to Shallow Cylindrical Panel
    Harmonic Response of a System in Terms of Its Component Receptances
    Dynamic Absorber
    Harmonic Force Applied Through a Spring
    Steady-State Response to Harmonic Displacement Excitation
    Complex Receptances
    Stiffening of Shells
    Two Systems Joined by Two or More Displacement
    Suspension of an Instrument Package in a Shell
    Subtracting Structural Subsystems
    Three and More Systems Connected
    Examples of Three Systems Connected to Each Other
    References
    Hysteresis Damping
    Equivalent Viscous Damping Coefficient
    Hysteresis Damping
    Direct Utilization of Hysteresis Model in Analysis
    Hysteretically Damped Plate Excited by Shaker
    Steady State Response to Periodic Forcing
    References
    Shells Made of Composite Material
    Nature of Composites
    Lamina-Constitutive Relationship
    Laminated Composite
    Equation of Motion
    Orthotropic Plate
    Circular Cylindrical Shell
    Orthotropic Nets or Textiles Under Tension
    Hanging Net or Curtain
    Shells Made of Homogeneous and Isotropic Lamina
    Simply Supported Sandwich Plates and Beams Composed of Three Homogeneous and Isotropic Lamina
    References
    Rotating Structures
    String Parallel to Axis of Rotation
    Beam Parallel to Axis of Rotation
    Rotating Ring
    Rotating Ring Using Inextensional Approximation
    Cylindrical Shell Rotating with Constant Spin About Its Axis
    General Rotations of Elastic Systems
    Shells of Revolution with Constant Spin About Their Axes of Rotation
    Spinning Disk
    References
    Thermal Effects
    Stress Resultants
    Equations of Motion
    Plate
    Arch, Ring, Beam, and Rod
    Limitations
    Elastic Foundations
    Equations of Motion for Shells on Elastic Foundations
    Natural Frequencies and Modes
    Plates on Elastic Foundations
    Ring on Elastic Foundation
    Donnell-Mushtari-Vlasov Equations with Transverse Elastic Foundation
    Forces Transmitted Into the Base of the Elastic Foundation
    Vertical Force Transmission Through the Elastic Foundation of a Ring on a Rigid Wheel
    Response of a Shell on an Elastic Foundation to Base Excitation
    Plate Examples of Base Excitation and Force Transmission
    Natural Frequencies and Modes of a Ring on an Elastic Foundation in Ground Contact at a Point
    Response of a Ring on an Elastic Foundation to a Harmonic Point Displacement
    References
    Similitude
    General Similitude
    Derivation of Exact Similitude Relationships for Natural Frequencies of Thin Shells
    Plates
    Shallow Spherical Panels of Arbitrary Contours (Influence of Curvature)
    Forced Response
    Approximate Scaling of Shells Controlled by Membrane Stiffness
    Approximate Scaling of Shells Controlled by Bending Stiffness
    References
    Interactions with Liquids and Gases
    Fundamental Form in Three-Dimensional Curvilinear Coordinates
    Stress-Strain-Displacement Relationships
    Energy Expressions
    Equations of Motion of Vibroelasticity with Shear
    Example: Cylindrical Coordinates
    Example: Cartesian Coordinates
    One-Dimensional Wave Equations for Solids
    Three-Dimensional Wave Equations for Solids
    Three-Dimensional Wave Equations for Inviscid Compressible Liquids and Gases (Acoustics)
    Interface Boundary Conditions
    Example: Acoustic Radiation
    Incompressible Liquids
    Example: Liquid on a Plate
    Orthogonality of Natural Modes for Three-Dimensional Solids, Liquids, and Gases
    References
    Discretizing Approaches
    Finite Differences
    Finite Elements
    Free and Forced Vibration Solutions
    References
    Index

    Biography

    Werner Soedel