Upper and Lower Bounds for the Eigenvalues of Vibrating Beams with Linearly Varying Axial Load

Abstract

Previous investigations have demonstrated the importance of the effect of linearly varying axial or in-plane loading on the vibration characteristics of beams and flat plates. It has already been established that the problem reduces to solving for the eigenvalues of a fourth order, variable coefficient differential equation that can not be solved in closed form. Beginning with a variational representation of the eigenvalue problem, methods are discussed by which both upper and lower bounds for the eigenvalues may be formed, The true eigenvalues may thus be estimated as being bracketed by the upper and lower bounds which are shown to approach each other. The bounds for the eigenvalues may also be estimated by an averaging procedure which may or may not compare favorably with the true values depending on the values of the loading parameters. Finally, numerical values for upper bounds, lower bounds, and average lumped end-load eigenvalues are computed on an IBM 7090 Computer.

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Document Details

Document Type
Technical Report
Publication Date
Nov 01, 1966
Accession Number
ADA394967

Entities

People

  • Guy Fauconneau
  • William M. Laird

Organizations

  • University of Pittsburgh

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Aerospace Industry
  • Axial Loads
  • Bibliographies
  • Boundaries
  • Buckling
  • Coefficients
  • Computers
  • Data Processing
  • Differential Equations
  • Eigenvalues
  • Eigenvectors
  • Engineering
  • Equations
  • Frequency
  • Real Variables
  • Resonant Frequency
  • Vibration

Readers

  • Linear Algebra
  • Regression Analysis.
  • Structural Dynamics.