On an Extremum Principle for Mode Form Solutions in Plastic Structural Dynamics.

Abstract

An extremum principle of Lee and Martin, for mode form solutions of a structure deforming plastically as result of dynamic loading, is discussed with special reference to conditions for the extrema to be stationary, with vanishing first variation of a functional of kinematically admissible velocity fields. Three classes of material behavior are treated: rigid-perfectly plastic, rigid-viscoplastic, and viscous, the last having no yield function. The authors illustrate various forms of these which are realistic as well as convenient in problems of plastic dynamics of structures. For all three classes of material, the authors show that stationary extrema occur under certain conditions, but may be regarded as exceptional. The properties of the extrema for structures are illustrated by means of a simple discrete structure model with two masses.

Document Details

Document Type
Technical Report
Publication Date
Nov 01, 1974
Accession Number
ADA004294

Entities

People

  • Paul S. Symonds
  • Tomasz Wierzbicki

Organizations

  • Brown University

Tags

DTIC Thesaurus Topics

  • Dynamics
  • Fluid Mechanics
  • Fluid Statics
  • Materials
  • Mechanics
  • Physics
  • Stationary
  • Stratified Fluids

Fields of Study

  • Mathematics

Readers

  • Adaptive Control and Estimation with Uncertainty in Dynamic Systems.
  • Structural Dynamics.