Integrated Research on Carbon Composite Materials. Volume 2. Structural Mechanics

Abstract

Optimization studies (minimum weight design) OF STIFFENED CYLINDERS SIMILAR TO THE FUSELAGE COMPONENT WERE CARRIED OUT BY TWO DIFFERENT TECHNIQUES. The behavior of composite structural elements was investigated in plate-buckling and post- buckling studies, buckling of stiffened plates with cutouts, and application of shell theory to anisotropic cylinders. Micromechanics studies of fibrous composites included development of a photoelastic technique for analyzing frozen stresses, a discrete element microstress analysis of unidirectional fiber composites, an application of the theory of physically nonlinear elastic solids to composite materials, and an investigation of the multiple circular inclusion problem in plane elastostatics. Failure of composite structural elements was investigated through studies of the failure mechanism for off- axis composites, the fracture toughness of composites, the effect of fatigue and sustained loads of cross-plied composites, the notch sensitivity of cross-plied composites, and the effect of a variety of known intentionally interjected defects on the fracture strength. Multiaxial stress testing of composite cylinders was included. The effects of circular and square cutouts in flat panels and in a stiffened panel, and methods of reinforcement of cutouts were investigated and correlated with predications based on discrete element analysis.

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1971
Accession Number
AD0882535

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Creep
  • Elastic Properties
  • Failure Mode And Effect Analysis
  • Finite Element Analysis
  • Geometry
  • Materials
  • Materials Laboratories
  • Materials Processing
  • Materials Science
  • Materials Testing
  • Mechanical Properties
  • Mechanical Working
  • Mechanics
  • Stress Strain Relations
  • Tensile Strength
  • Three Dimensional
  • Two Dimensional

Readers

  • Computational Modeling and Simulation
  • Materials Science (Mechanical Engineering).
  • Structural Dynamics.