Experimental identification of nonlinear structural models

Conference · Fri Jan 01 04:00:00 EST 1988

OSTI ID:5792155

Paez, T L; Hunter, N F

A fundamental objective of structural dynamic engineering is to understand the behavior of physical structures subjected to field environments. In practical situations, many structures execute nonlinear motions, and under the influence of extreme excitations structures often show strongly nonlinear responses. Recent investigations have shown that the Volterra model provides a means for system characterization that holds great potential for the description of nonlinear structural response. Simulations have shown that when the Volterra model of a structure is available, it can provide a reasonable match to numerically simulated nonlnear response. The present investigation considers the identification of the functions used in the Volterra model for physical structures tested in the laboratory. It is shown that the frequency form of the Volterra functions can be estimated directly using measured excitation and response data. A coherence-like measure of the observed structural response and the nonlinear model is developed, and it is shown that this quantity can be used to evaluate the accuracy of the nonlinear structural model. Finally, the characteristics of structures most suitably modelled by the Volterra series are discussed. 8 refs., 8 figs.

• Research Organization: Sandia National Labs., Albuquerque, NM (USA); Los Alamos National Lab., NM (USA)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 5792155
• Report Number(s): LA-UR-87-3582; CONF-880220-2; ON: DE88001795
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420200* -- Engineering-- Facilities
Equipment
& Techniques
EQUATIONS
FOURIER TRANSFORMATION
FREQUENCY DEPENDENCE
FUNCTIONS
INTEGRAL EQUATIONS
INTEGRAL TRANSFORMATIONS
NONLINEAR PROBLEMS
PHASE SHIFT
SPECTRAL DENSITY
SPECTRAL FUNCTIONS
STRUCTURAL MODELS
TRANSFORMATIONS
VOLTERRA INTEGRAL EQUATIONS