A Koiter-Type Method for Finite Element Analysis of Nonlinear Structural Behavior. Volume I. The Modified Structure Method.

Abstract

Koiter's method for the asymptotic analysis of post-buckling behavior is reformulted in finite element notation for application to structures idealized by finite element models. Koiter's method is herein adapted to a general class of structures exhibiting the common snap-through (limit point) type of buckling. This is referred to as the Modified Structure method. It is accomplished by modification of the actual energy functional to create a hypothetical modified structure having a strictly linear pre-buckling path along which buckling must be of the bifurcation type. The analysis of the actual structure is then accomplished by application of Koiter's method through consideration of the actual structure as an imperfect version of the modified structure. The effects of pre-buckling nonlinearity are approximated asymptotically. The use of the Modified Structure method in conjunction with direct methods of nonlinear analysis is examined. A highly accurate finite element representation is employed in presenting a comprehensive numerical evaluation of the Modified Structure method of analysis on the basis of a number of planar frame problems. (Author)

Document Details

Document Type
Technical Report
Publication Date
Nov 01, 1970
Accession Number
AD0717740

Entities

People

  • R. H. Mallett
  • R. T. Haftka
  • W. Nachbar

Organizations

  • University of California, San Diego

Tags

DTIC Thesaurus Topics

  • Buckling
  • Finite Element Analysis
  • Mathematical Analysis
  • Nonlinear Analysis
  • Notation
  • Test And Evaluation

Fields of Study

  • Engineering

Readers

  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Structural Dynamics.
  • Theoretical Analysis.