Fission-Fusion Adaptivity in Finite Elements for Nonlinear Dynamics of Shells

Abstract

The objective of this work was to develop adaptive finite element analysis methods for nonlinear structural dynamics. Adaptive methods are particularly promising for nonlinear problems involving failure, because in failure and near-failure states of structures, three predominant phenomena are; buckling, shear banding, and fracture. These phenomena are associated with localization of the deformation, by which is meant the development of large strains in small regions of the structure, which is accompanied by large gradients in the strain. While strains are distributed in elastic buckling, once plasticity develops a large part of the deformation of beams or shells usually occurs over narrow zone called hingelines. Shear banding is a result of strain softening material behavior and is also associated with narrow bands of highly strained material. In fracture, high strain gradients occur at the crack tip, and in addition the displacement field is discontinuous behind the crack tip. In this work, adaptive methods are developed for the nonlinear dynamics of shells with both geometric and material nonlinearities. The localization phenomenon which is of primary interest in this class of problems is hingeline formation, but aspects of this work should be applicable to other localization phenomena in structural dynamics.

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Document Details

Document Type
Technical Report
Publication Date
Aug 30, 1990
Accession Number
ADA238029

Entities

People

  • Ted Belytschko

Organizations

  • Northwestern University

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Accuracy
  • Applied Mechanics
  • Buckling
  • Civil Engineering
  • Computer Programs
  • Computers
  • Dissipation
  • Dynamics
  • Engineering
  • Errors
  • Finite Element Analysis
  • Geometry
  • Materials
  • Mechanics
  • Nonlinear Dynamics
  • Shape
  • Shear Bands

Fields of Study

  • Engineering

Readers

  • Adaptive Control and Estimation with Uncertainty in Dynamic Systems.
  • Mechanical Engineering/Mechanics of Materials.
  • Structural Dynamics.