This article discusses the use of frequency domain transmissibility functions for detecting, locating, and quantifying damage in linear and nonlinear structures. Structural damage affects both the system poles and zeros; however, zeros are much more sensitive than poles to localized damage. This is because zeros depend on the input and output locations whereas poles do not. It is demonstrated here that since transmissibility functions are determined solely by the system zeros, they are potentially better indicators of localized linear and nonlinear types of damage. Furthermore, excitation measurements are not required to compute transmissibility functions so damage indices can be calculated directly from response measurements. It is also demonstrated that sensor arrays can sometimes be used to yield mixed transmissibility functions that are differential in nature, that is, they are less sensitive to gross fluctuations in the dynamic loading or environmental variables.

1.
Cronkhite, J. D., and Gill, L., technical evaluators, “RTO MP-7,” 1998, RTO AVT Specialists’ Meeting on Exploitation of Structural Loads/Health Data for Reduced Life Cycle Costs, Brussels, Belgium.
2.
Doebling, S. W., Farrar, C. R., Prime, M. B., and Shevitz, D. W., 1996, “Damage Identification and Health Monitoring of Structural and Mechanical Systems from Changes in Their Vibration Characteristics: A Literature Review,” Los Alamos Report LA-13070-MS.
3.
Zimmerman, D. C., Kaouk, M., and Simmermacher, T., 1995, “Structural Damage Detection Using Frequency Response Functions,” Proceedings of the International Modal Analysis Conference, pp. 179–184.
4.
Schulz, M. J., Pai, P. F., and Abdelnaser, A. S., 1996, “Frequency Response Function Assignment Technique for Structural Damage Identification,” Proceedings of the International Modal Analysis Conference, pp. 105–111.
5.
Schulz, M. J., Pai, P. F., Naser, A. S., Thyagarajan, S. K., Brannon, G. R., and Chung, J., 1997, “Locating Structural Damage Using Frequency Response Reference Functions and Curvatures,” Proceedings of the International Workshop on Structural Health Monitoring, pp. 690–701, F. K. Chang, ed., Stanford University, Technomic Publishing.
6.
Schulz, M. J., Pai, P. F., Naser, A. S., Linville, M., and Chung, J., 1997, “Detecting Structural Damage Using Transmittance Functions,” Proceedings of the International Modal Analysis Conference, Orlando, FL, pp. 638–644.
7.
Ribeiro
,
A. M. R.
,
Silva
,
J. M. M.
, and
Maia
,
N. M. M.
,
2000
, “
On the Generalisation of the Transmissibility Concept
,” January,
Mech. Syst. Signal Process.
,
14
(
1
), pp.
29
36
.
8.
Mottershead
,
J. E.
,
2000
, “
On the Zeros of Structural Frequency Response Functions and Their Sensitivities,” January
,
Mech. Syst. Signal Process.
,
12
(
5
), pp.
591
598
.
9.
Adams
,
D. E.
, and
Allemang
,
R. J.
,
1999
, “
A New Derivation of the Frequency Response Function Matrix for Vibrating Nonlinear Systems
,”
J. Sound Vib.
,
227
(
5
), pp.
1083
1108
.
10.
Adams
,
D. E.
, and
Allemang
,
R. J.
,
1999
, “
Characterization of Nonlinear Vibrating Systems Using Internal Feedback and Frequency Response Modulation
,”
ASME J. Vibr. Acoust.
,
121
(
4
), pp.
495
500
.
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