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A trajectory method for vibration based damage identification of underdetermined problems
Author(s) -
Chatzieleftheriou Stavros,
Lagaros Nikos D.
Publication year - 2017
Publication title -
structural control and health monitoring
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.587
H-Index - 62
eISSN - 1545-2263
pISSN - 1545-2255
DOI - 10.1002/stc.1883
Subject(s) - robustness (evolution) , underdetermined system , control theory (sociology) , vibration , inverse problem , normal mode , trajectory , nonlinear system , identification (biology) , computer science , stiffness , mathematical optimization , algorithm , mathematics , engineering , structural engineering , artificial intelligence , physics , mathematical analysis , biochemistry , chemistry , botany , control (management) , quantum mechanics , astronomy , biology , gene
Summary The problem of structural damage identification based on vibration measurements (eigenfrequencies and incomplete mode shapes) is generally formulated as an inverse problem aiming to identify changes encountered on the global stiffness matrix. In most cases, the measured quantities are less than the damage parameters to be identified; thus, an infinite number of possible damage configurations are expected to satisfy the measurements. Therefore, damage identification problems are often proven to be ill‐conditioned. The problem becomes more complex when measurements' noise and model uncertainties are considered. Therefore, depending on the structural system, damage scenario and available vibration measurements, additional eigenmode data may need to be considered in order to increase the robustness of the damage identification procedure. In this work, a new two‐loop trajectory method is presented, that relies on an iterative nonlinear sensitivity analysis procedure. The main advantage of the proposed method is its ability to identify damage scenarios that match the measured data with high accuracy as well as to explore effectively the solution space. This feature can be exploited in order to assess the adequacy of the measurements in noisy and/or uncertain environment. Copyright © 2016 John Wiley & Sons, Ltd.