Fracture Prediction in Elastic-Plastic Problems Using Finite Element Method

  • A. R. Kukreti
  • A. S. Khan
  • A. Iranmanesh
Conference paper

Abstract

A general finite element program, based on the plane stress assumption, is presented to analyze elastic-plastic problems involving monotonically increasing loads. The fracture program presented directly predicts the initiation of fracture and the failure load in any isotropic planar structure. The approach uses a piecewise linear approximation of the nonlinear plastic region of the actual stress-strain curve for the material. The program has the option to use failure criterion based on either the maximum principal strain theory (St. Venant) or the maximum energy of distortion (Hencky-von Mises). The predictions using this program are shown to agree well with published experimental data.

In order to facilitate the finite element computations, such as nodal coordinates, element connectivity array, and boundary information, etc., a separate mesh processor program is developed. In this program, user-defined isoparametric superlements are subdivided, as specified by the user into 3-noded triangular elements or into 4-noded or 8-noded isoparametric quadrilaterals. Geometric characteristics at the superelement nodes are mapped so as to provide the appropriate nodal values for the superelements. Material specification codes from the parent superelements are also transformed as subelement characteristics. An automatic node numbering scheme is included to minimize the bandwidth of the generated fine mesh system’s stiffness matrix

Keywords

Fatigue Crack Growth Fine Mesh Fracture Load Finite Element Program Loaded Node 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
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Copyright information

© Martinus Nijhoff Publishers, The Hague 1984

Authors and Affiliations

  • A. R. Kukreti
    • 1
  • A. S. Khan
    • 1
  • A. Iranmanesh
    • 1
  1. 1.University of OklahomaNormanUSA

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