Numerical Methods for the Nonlinear Analysis of an Elastic Arch

Abstract

In a recent paper, Wempner presented a method by which the finite deflections of thin shells are approximated in finite elements and the nonlinear differential equations are replaced by nonlinear algebraic equations. This is accomplished by decomposing the motion of an element into a rigid-body rotation and a deformation. The deformation of a Hookean element is characterized by linear constitutive equations relating generalized forces and small relative displacements. Nonlinearities arise from the differences in the rigid-body rotations of adjacent elements. In the present paper, the method is applied to formulate algebraic equations for the finite deflections of a circular arch. The constitutive equations of the finite element are the exact linear equations of the Winkler-Bach theory. The nonlinear algebraic equations are replaced by a succession of linear equations, each governing the response to a small increment of load. To eliminate cumulative error, the numerical results are inserted in the nonlinear equations and corrected by the Newton-Raphson procedure.

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1968
Accession Number
AD0846250

Entities

People

  • Grady E. Jr Patrick

Organizations

  • United States Army Aviation and Missile Command

Tags

Communities of Interest

  • Energy and Power Technologies
  • Weapons Technologies

DTIC Thesaurus Topics

  • Applied Mechanics
  • Boundaries
  • Buckling
  • Computer Programs
  • Constitutive Equations
  • Continuum Mechanics
  • Deflection
  • Differential Equations
  • Displacement
  • Equations
  • Equations Of State
  • Export Controls
  • Exports
  • Finite Element Analysis
  • Geometry
  • Governments
  • Mechanics
  • New York
  • Nonlinear Algebraic Equations
  • Nonlinear Differential Equations
  • Numerical Analysis

Fields of Study

  • Mathematics

Readers

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