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Modal–Vibration-Based Damage Identification

Physical Monitoring Principles

Passive and Active Measurements with Data Analysis Approaches for Load and Damage Identification

  1. Keith Worden1,
  2. Michael I. Friswell2

Published Online: 15 SEP 2009

DOI: 10.1002/9780470061626.shm013

Encyclopedia of Structural Health Monitoring

Encyclopedia of Structural Health Monitoring

How to Cite

Worden, K. and Friswell, M. I. 2009. Modal–Vibration-Based Damage Identification. Encyclopedia of Structural Health Monitoring. .

Author Information

  1. 1

    University of Sheffield, Department of Mechanical Engineering, Sheffield, UK

  2. 2

    University of Bristol, Department of Aerospace Engineering, Bristol, UK

Publication History

  1. Published Online: 15 SEP 2009


A substantial body of structural health monitoring (SHM) research has been carried out in the context of structural dynamics. In this context, it is natural to make use of features for damage identification, which arise in the normal course of structural dynamic testing. The accepted standard for a dynamic test is a modal analysis, which derives a description of the dynamics in terms of natural frequencies, damping ratios, and modeshapes. This article discusses how such features can be used to extract a damage diagnosis. From a modal test, it is possible to extract the physical matrices that enter the structural equations of motion: mass, damping, and stiffness matrices. This article also describes damage identification strategies based on these matrices.


  • vibration-based SHM;
  • modal properties;
  • modal features;
  • physical matrices;
  • curvatures;
  • update methods;
  • sensitivity analysis;
  • optimisation;
  • regularisation