THE EFFECT OF VARIATIONS IN THE CREEP EXPONENT n ON THE BUCKLING OF CIRCULAR CYLINDRICAL SHELLS IN AXIAL COMPRESSION,

Abstract

The purpose of the investigation is to determine the effect of creep on the load carrying capability of axially symmetric circular cylinders when subjected to uniform axial compression. In particular, the effect of variation of the creep exponent in Odgvist's bi-axial creep law for creep, is investigated. The analysis of the problem is undertaken in the cases in which the creep exponent has the value one and five. Closed form analytical results are presented for the cases in which the creep exponent has the value one, three, and five. Two numerical procedures are developed. The first generates the governing equations of the creep problem symbolically, while the second solves these equations. Numerical results are presented for the cases in which the creep exponent has the value three, five, seven, and nine. The numerical results are compared with the analytical results. While the numerical programs offer a means of further extending the range of values of the creep exponent, this is carried out instead by two empirical methods, which are based on the numerical results already obtained. The case in which the creep exponent becomes unbounded is considered analytically. Dimensionless plots of radial displacement versus time are presented for each value of the creep exponent, and for a variety of values of initial imperfections in the shell wall. A simple graphical method is developed by which the plot for any given value of the initial imperfection may be obtained from another similar plot for which the value of the initial imperfection is smaller than the given value. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1970
Accession Number
AD0711949

Entities

People

  • Nicholas J. Hoff
  • Terence C. Honikman

Organizations

  • Stanford University

Tags

DTIC Thesaurus Topics

  • Buckling
  • Compression
  • Displacement
  • Equations
  • Failure (Mechanics)
  • Mathematics

Readers

  • Calculus or Mathematical Analysis
  • Mechanical Engineering/Mechanics of Materials.
  • Structural Dynamics.