Identification of Structural Systems from Measured Response

Banan, Mohammad Reza; Hjelmstad, K.D.

Permalink

https://hdl.handle.net/2142/14196 Copy

Description

Title

Identification of Structural Systems from Measured Response

Author(s)

• Banan, Mohammad Reza
• Hjelmstad, K.D.

Issue Date

1993-05

Keyword(s)

• System identification
• Optimization
• Parameter estimation
• Finite element models

Abstract

This report presents an approach to the problem of parameter estimation of finite element models of complex structural systems using measured response. The method computes the element constitutive parameters of a finite element model of a structure by finding a constrained nonlinear minimum of the difference between the measured response of the real structure and the computed response of a finite element model of the structure. Constraints are used to bound the constitutive parameters. The optimization problem is solved by the method of Recursive Quadratic Programming. A simple and straightforward method of computing the gradient of the loss function on an element-by-element basis is presented. The method presented herein has been implemented as a general purpose parameter estimation program for structural systems. This program has all the flexibilities of a general purpose finite element package in that it can treat complex structures with different topologies, geometries, and element types. It is suited to static, modal dynamic, or forced dynamic response, sparsely sampled in space, time, and state. We consider both an equation-error estimator and an output-error estimator for the static and modal dynamic problems, and an equation-error estimator for the forced dynamic problem. Monte Carlo simulation is used to study the behavior of the parameter estimation algorithms in the presence of noise in the measurements. Extensive simulations are carried out for both the static and forced dynamic cases. A case study, using real field measurements is presented for the modal dynamic case.

Publisher

University of Illinois Engineering Experiment Station. College of Engineering. University of Illinois at Urbana-Champaign.

Series/Report Name or Number

Civil Engineering Studies SRS-579

Type of Resource

text

Language

en

Permalink

http://hdl.handle.net/2142/14196

Sponsor(s)/Grant Number(s)

• National Science Foundation Grant CES 86-58109
• Army Research Grants DAAL-03-87-K-006, DAAL-03-86-G-0186, and DAAL-03-86-K-0188

Owning Collections