Equivalent Viscous Damping of Elasto-Plastic Systems under Sinusoidal Loading.

Abstract

This report addresses the possibility of establishing a simple algorithm applicable to structural design that would provide information on a nonlinear structural system based on information on a linear damped structural system. Two variables were considered -- geometrical stiffness and resonant amplitude. Although the geometrical stiffness approach was determined more adequate in accounting for the frequency shift in a nonlinear system, the maximum displacement values it displayed throughout the frequency range were unconservative. The resonant amplitude approach indicated more conservative values in an intermediate range of frequencies, but its lower range values, where nonlinear systems demonstrate resonance, were also unconservative. This report determines that the application of a weighted average of linear viscous damped system displacement to define nonlinear system displacement does not provide a satisfactory method of equivalencing systems by either the resonant amplitude or geometrical stiffness approach. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jul 01, 1978
Accession Number
ADA057225

Entities

People

  • R. G. Merritt

Organizations

  • Construction Engineering Research Laboratory

Tags

DTIC Thesaurus Topics

  • Accounting
  • Algorithms
  • Amplitude
  • Displacement
  • Frequency
  • Frequency Shift
  • Nonlinear Systems
  • Resonance
  • Stiffness

Fields of Study

  • Engineering

Readers

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