An application of operational deflection shapes and spatial filtration for damage detection

  • Mendrok, Krzysztof ;
  • Wojcicki, Jeremi ;
  • Uhl, Tadeusz
  • Received : 2014.08.22
  • Accepted : 2015.10.05
  • Published : 2015.12.25


In the paper, the authors propose the application of operational deflection shapes (ODS) for the detection of structural changes in technical objects. The ODS matrix is used to formulate the spatial filter that is further used for damage detection as a classical modal filter (Meirovitch and Baruh 1982, Zhang et al. 1990). The advantage of the approach lies in the fact that no modal analysis is required, even on the reference spatial filter formulation and other components apart from structural ones can be filtered (e.g. harmonics of rotational velocity). The proposed methodology was tested experimentally on a laboratory stand, a frame-like structure, excited from two sources: an impact hammer, which provided a wide-band excitation of all modes, and an electro-dynamic shaker, which simulated a harmonic component in the output spectra. The damage detection capabilities of the proposed method were tested by changing the structural properties of the model and comparing the results with the original ones. The quantitative assessment of damage was performed by employing a damage index (DI) calculation. Comparison of the output of the ODS filter and the classical modal filter is also presented and analyzed in the paper. The closing section of the paper describes the verification of the method on a real structure - a road viaduct.


modal filter;spatial filter;operational deflection shapes;damage detection


  1. Andersen, P., Brincker, R., Peeters, B., De Roeck, G., Hermans, L. and Kramer, C. (1999), "Comparison of system identification methods using ambient bridge test data", Proceedings of the 17th International Modal Analysis Conference, Kissimee FL, February.
  2. Asnaashari E. and Sinha J.K. (2014), "Development of residual operational deflection shape for crack detection in structures", Mech. Syst. Signal Pr., 3(1-2), 113-123
  3. Bahlous, S.E.O., Abdelghani, M., Smaoui, H. and El-Borgi, S. (2007), "A modal filtering and statistical approach for damage detection and diagnosis in structures using ambient vibrations measurements", J. Vib. Control, 13(3), 281-308.
  4. Carden, E.P. and Fanning, P. (2004), "Vibration based condition monitoring: a review", Struct. Health Monit., 3(4), 355-377.
  5. Deraemaeker, A. and Preumont, A. (2006), "Vibration based damage detection using large array sensors and spatial filters", Mech. Syst. Signal Pr., 20(7), 1615-1630.
  6. Doebling, S.W., Farrar, C.R. and Prime, M.B. (1998), "A summary review of vibration-based damage identification methods", Shock Vib. Dig., 30(2), 91-105.
  7. Gawronski, W. and Sawicki, J.T. (2000), "Structural damage detection using modal norms", J. Sound Vib., 229(1), 194-198.
  8. Holford, K.M. (2009), "Acoustic emission in structural health monitoring", Key Eng. Mater., 413, 15-28.
  9. Hou, J., Jankowski, L. and Ou, J. (2011), "A substructure isolation method for local structural health monitoring", Struct. Control Health Monit., 18, 601-618.
  10. Hou, J., Jankowski, L. and Ou, J. (2013), "An online substructure identification method for local structural health monitoring", Smart Mater. Struct., 22(9), art. no. 095017.
  11. Klepka, A., Staszewski, W.J., Jenal, R.B., Szwedo, M., Iwaniec, J. and Uhl, T. (2012a), "Nonlinear acoustics for fatigue crack detection-experimental investigations of vibro-acoustic wave modulations", Struct. Health Monit., 11(2), 197-211.
  12. Klepka, A., Staszewski, W.J., Uhl, T., Di Maio, D., Scarpa, F. and Tee, K.F. (2012b), "Impact damage detection in composite chiral sandwich panels", Key Eng. Mater., 518, 160-167.
  13. Law, S.S., Zhang, K. and Duan, Z.D. (2010), "Structural damage detection from coupling forces between substructures under support excitation", Eng. Struct., 32(8), 2221-2228.
  14. Lisowski, W. (2003), "An example of model consolidation in autonomous modal analysis (in Polish)", Problems of Modal Analysis of Mechanical Structures - Collective Work Edited by Tadeusz Uhl, KRiDM Publisher, AGH, Krakow, Poland.
  15. Manka, M., Rosiek, M., Martowicz, A., Stepinski, T. and Uhl, T. (2013), "Lamb wave transducers made of piezoelectric macro-fiber composite", Struct. Control Health Monit., 20(8), 1138-1158.
  16. McHargue, P.L. and Richardson, M.H. (1993), "Operating deflection shapes from time versus frequency domain measurements", Proceedings of the 11th International Modal Analysis Conference, Orlando FL, February.
  17. Meirovitch, L. and Baruh, H. (1982), "Control of self-adjoin distributed-parameter systems", J. Guid. Control Dynam., 5(1), 60-66.
  18. Mendrok, K. and Kurowski, P. (2013), "Operational modal filter and its applications", Arch. Appl. Mech., 83(4), 509-519.
  19. Mendrok, K. and Uhl, T. (2008), "Modal filtration for damage detection and localization", Proceedings of the 4th EWoSHM, Krakow, July.
  20. Mendrok, K. and Uhl, T. (2010), "The application of modal filters for damage detection", Smart Struct. Syst., 6(2), 115-133.
  21. Mendrok, K. and Uhl, T. (2011), "Experimental verification of the damage localization procedure based on modal filtering", Struct. Health Monit., 10(2), 157-171.
  22. Mendrok, K., Uhl, T. and Bednarz, J. (2009), "Application of modal filtration for damage detection of rotating shaft", Key Eng.Mater., 413, 373-380.
  23. Pieczonka, L., Aymerich, F., Brozek, G., Szwedo, M., Staszewski, W.J. and Uhl, T. (2013), "Modelling and numerical simulations of vibrothermography for impact damage detection in composites structures", Struct. Control Health Monit., 20(4), 626-638.
  24. Schwarz, B.J. and Richardson, M.H. (1999), "Introduction to operating deflection shapes", CSI Reliability Week, 10, 121-126.
  25. Slater, G.L. and Shelley, S.J. (1993), "Health monitoring of flexible structures using modal filter concepts", Proceeding of SPIE, 1917, 997-1008.
  26. Uhl, T., Lisowski, W. and Kurowski, P. (2001), In-operation modal analysis and its applications, KRiDM Publisher, AGH , Krakow, Poland
  27. Wentzel, H. (2013), "Fatigue test load identification using weighted modal filtering based on stress", Mech. Syst. Signal Pr., 40(2), 618-627.
  28. Wojcicki, J., Mendrok, K. and Uhl, T. (2013), "Spatial filter for operational deflection shape component filtration", Key Eng. Mater., 569, 868-875.
  29. Zhang, Y., Lie, S.T. and Xiang, Z. (2013), "Damage detection method based on operating deflection shape curvature extracted from dynamic response of a passing vehicle", Mech. Syst. Signal Pr., 35(1-2), 238-254
  30. Zhang, Q., Allemang, R.J. and Brown, D.L. (1990), "Modal filter: concept and applications", Proceedings of the 8th International Modal Analysis Conference, January.