Eventos Anais de eventos
DINAME 2017
XVII International Symposium on Dynamic Problems of Mechanics
REGULARIZATION OF THE INVERSE PROBLEM OF DAMAGE IDENTIFICATION USING THE MODIFIED SEQUENTIAL ALGEBRAIC ALGORITHM
Submission Author:
Josué Costa Baptista , RJ
Co-Authors:
Josué Costa Baptista, Roberto Tenenbaum, Filipe Taminato
Presenter: Roberto Tenenbaum
doi://10.26678/ABCM.DINAME2017.DIN17-0139
Abstract
The modified sequential algebraic algorithm (MSAA) is a routine developed to solve the longitudinal acoustic wave propagation problem in inhomogeneous media. This method accurately predicts the echo generated by the inhomogeneities, particularly when the acoustic impedance variation profile in the damaged part of the structure is non-smooth. Used for solving the inverse problem by a stochastic optimization approach, MSAA shows to be efficient to identify rough profiles of impedance with low noise level in the input data. As noise level increases, the inverse problem turns out to be `ill-posed' and often yields inappropriate solutions. The purpose of this paper is to apply a regularization scheme to reduce the error in the damage estimation. In the numerical examples 40 parameters are successfully identified for a signal to noise ratio of 20 dB. The regularization procedure decreased the maximum absolute error to levels lower than 6 %, and for the roughest impedance profile, the mean squared error was reduced by more than one order of magnitude and the error propagation avoided.
Keywords
Structural damage identification, Acoustic wave propagation, Inverse problem, Regularization, Noisy data, Inverse problems
