CREEP BUCKLING OF A NONLINEARLY VISCOELASTIC BEAM-COLUMN.

Abstract

The stability of an initially crooked, simply-supported, H-section beam-column, subjected to an axial compressive load, is investigated. The material of the column is taken to behave as a general nonlinear viscoelastic solid. It is assumed that the constitutive relation of the material can be represented by a Volterra-Frechet functional polynomial. Conditions sufficient to assure instantaneous, short term and long term (i.e., asymptotic) stability are established. It is shown that complete knowledge of the material creep functions (i.e., the kernels appearing in the functional polynomial representation of the stress-strain relation) is not required in order to determine stability conditions. A program of experiments to characterize the material for stability studies is presented. A formal analogy for instantaneous and short term stability conditions is established between the column under consideration and an initially straight, concentrically loaded column fabricated from an imaginary, non-linearly viscoelastic material. The relationship between the actual visco-elastic material under consideration and the imaginary viscoelastic material is explicitly given. A further analogy-this one between the asymptotic stability of the column under consideration and the stability of a fictitious, nonlinearly elastic column - is also established. (Author)

Document Details

Document Type
Technical Report
Publication Date
Mar 01, 1967
Accession Number
AD0813360

Entities

People

  • J. L. Sackman
  • J. N. Distefano

Organizations

  • University of California, Berkeley

Tags

DTIC Thesaurus Topics

  • Buckling
  • Elastic Materials
  • Materials
  • Mechanical Properties
  • Physical Properties
  • Polynomials
  • Stability Conditions
  • Stress Strain Relations
  • Stresses

Fields of Study

  • Mathematics

Readers

  • Calculus or Mathematical Analysis
  • Structural Dynamics.