DEVELOPMENT OF EXPERIMENTAL STRESS ANALYSIS METHODS TO DETERMINE STRESSES AND STRAINS IN SOLID PROPELLANT GRAINS. PHOTOELASTIC ANALYSIS OF FLEXURAL WAVES IN A BAR.

Abstract

A complete, direct, full-field optical determination of dynamic stress distributions is illustrated. The method is applied to the study of flexural waves propagating in a photoelastic, urethane rubber bar. A displacement type of transverse, dynamic loading (which has approximately the form of a decaying sine wave) is applied at one end of the bar. The loading pulse can be repeated with good precision. Individual isochromatics and isoclinics are obtained using a still camera with a short duration (0.5 microsecond) flash. A series of isochromatics have also been obtained with a Fastax high speed motion picture camera. Photoelastic data is supplemented by isopachic patterns obtained by a modified method of holographic interferometry recently developed by the authors. As an example of complete determination of stress distributions a vectorial representation of the principal stresses at one instant is given. Comparisons are made with approximate theories of flexural waves. (Author)

Document Details

Document Type
Technical Report
Publication Date
Apr 01, 1969
Accession Number
AD0688149

Entities

People

  • Augusto J. Durelli
  • J. A. Clark

Organizations

  • The Catholic University of America

Tags

DTIC Thesaurus Topics

  • Cameras
  • Motion Picture Cameras
  • Motion Pictures
  • Propellant Grains
  • Propellants
  • Sine Waves
  • Solid Propellants
  • Stress Analysis
  • Stresses
  • Waves

Fields of Study

  • Physics

Readers

  • Geodesy
  • Image Processing and Computer Vision.
  • Mechanical Engineering/Mechanics of Materials.