This paper presents a method for locating structural damage using experimental vibration data. The method uses measured frequency response functions to obtain displacement as a function of frequency. The displacement functions are converted to curvature functions, which are further processed to yield a damage index, displayed on a plot of position versus frequency. The method can be applied when there is no a priori knowledge about the undamaged structure, and it is suitable for automation. This paper details the theory of the broadband method, and the results of an experimental demonstration in which a steel beam was damaged with a narrow slot. It is shown that this proposed damage detection method is highly sensitive, and can locate a very small amount of damage. For example, the narrow slot was correctly located when there was only a 0.8 percent reduction in thickness in the beam. Traditionally, damage causes a change in natural frequencies, but at this small level of damage the frequency changes were within experimental error. Other published methods failed to locate the slot until it was significantly deeper. [S0739-3717(00)01403-3]

1.
Kashangaki, T. A. L., 1995, “Mode Selection for Damage Detection Using the Modal Sensitivity Parameter,” AIAA/ASME/ASCE/AHS Structures, Structural Dynamics & Materials Conference Collection of Technical Papers, 3, pp. 1535–1542.
2.
Hajela
,
P.
, and
Soeiro
,
F. J.
,
1990
, “
Structural Damage Detection Based on Static and Modal Analysis
,”
Am. Inst. Aeronaut. Astron. J.
,
28
, No.
6
, pp.
1110
1115
.
3.
Crema, L. B., Castellani, A., and Coppotelli, G., 1995, “Damage Localization in Composite Material Structures by Using Eigenvalue Measurements,” Materials and Design Technology, Petroleum Division Publication PD v71, American Society of Mechanical Engineers, New York, pp. 210–205.
4.
Cawley
,
P.
, and
Adams
,
R. D.
,
1979
, “
The Location of Defects in Structures from Measurements of Natural Frequencies
,”
J. Strain Anal.
,
14
, No.
2
, pp.
49
57
.
5.
Manning
,
R. A.
,
1994
, “
Structural Damage Detection Using Active Members and Neural Networks
,”
Am. Inst. Aeronaut. Astron. J.
,
32
, No.
6
, Technical Notes, pp.
1331
1333
.
6.
Liu
,
P. L.
,
1995
, “
Identification and Damage Detection of Trusses Using Modal Data
,”
J. Struct. Eng.
,
121
, No.
4
, pp.
599
607
.
7.
Chen
,
J. C.
, and
Garba
,
J. A.
,
1988
, “
On-orbit Damage Assessment for Large Space Structures
,”
Am. Inst. Aeronaut. Astron. J.
,
26
, No.
9
, pp.
1119
1126
.
8.
Li
,
C.
, and
Smith
,
S. W.
,
1995
, “
Hybrid Approach for Damage Detection in Flexible Structures
,”
J. Guid. Control Dyn.
,
18
, No.
3
, pp.
419
425
.
9.
Adams
,
R. D.
,
Brownjohn
,
J. M. W.
, and
Cawley
,
P.
,
1991
, “
Detection of Defects in GRP Lattice Structures by Vibration Measurements
,”
Nondestr. Test. Exam. Int. J.
,
24
, No.
3
, pp.
123
134
.
10.
Lim
,
T. W.
, and
Kashangaki
,
T. A. L.
,
1994
, “
Structural Damage Detection of Space Truss Structures Using Best Achievable Eigenvectors
,”
Am. Inst. Aeronaut. Astron. J.
,
32
, No.
5
, pp.
1049
1057
.
11.
Cawley
,
P.
, and
Adams
,
R. D.
,
1979
, “
A Vibration Technique for Non-destructive Testing of Fibre Composite Structures
,”
J. Compos. Mater.
,
13
, pp.
161
175
.
12.
Okafor, A. C., Chandrashekhara, K., and Jiang, Y. P., 1995, “Damage Detection in Composite Laminates with Built-in Piezoelectric Devices Using Modal Analysis and Neural Network,” Proceedings of SPIE—The International Society for Optical Engineering, Smart Structures and Materials: Smart Sensing, Processing, and Instrumentation, 2444, Society for Photo-Optical Instrumentation Engineers, Bellingham, WA.
13.
Peroni, I., Paolozzi, A., and Bramante, A., 1991, “Effect of Debonding Damage on the Modal Damping of a Sandwich Panel,” Proceedings of the 9th International Modal Analysis Conference, Society of Experimental Mechanics, 2, pp. 1617–1622.
14.
Vantomme
,
J.
,
1992
, “
Evaluation of Structural Joints in Composites with Modal Parameters
,”
J. Composite Struct.
,
22
, No.
4
, pp.
201
205
.
15.
Miller, R. A., Aktan, A. E., and Shahrooz, B. M., 1992, “Nondestructive and Destructive Testing of a Three Span Skewed R. C. Slab Bridge,” American Society of Civil Engineers Nondestructive Testing of Concrete Elements and Structures, pp. 150–161.
16.
Casas
,
J. R.
, and
Aparicio
,
A. C.
,
1994
, “
Structural Damage Identification from Dynamic-test Data
,”
J. Struct. Eng.
,
120
, No.
8
, pp.
2437
2450
.
17.
Liang, Z., Lee, G. C., and Kong, F., 1997, “On Detection of Damage Location of Bridges,” Proceedings of the 15th International Modal Analysis Conference, Society of Experimental Mechanics, 1, pp. 308–312.
18.
Chang, K. C., Shen, Z., and Lee, G. C., 1993, “Modal Analysis Technique for Bridge Damage Detection,” Proceedings of the Symposium of Structural Engineering, Natural Hazards and Mitigation, American Society of Civil Engineers, pp. 1083–1088.
19.
Yuen
,
M. M. F.
,
1995
, “
A Numerical Study of the Eigenparameters of a Damaged Cantilever
,”
J. Sound Vib.
,
103
, pp.
301
310
.
20.
Pandey
,
A. K.
,
Biswas
,
M.
, and
Samman
,
M. M.
,
1991
, “
Damage Detection from Changes in Curvature Mode Shapes
,”
J. Sound Vib.
,
145
, No.
2
, pp.
321
332
.
21.
Ratcliffe
,
C. P.
,
1997
, “
Damage Detection Using a Modified Laplacian Operator on Mode Shape Data
,”
J. Sound Vib.
,
204
, No.
3
, pp.
505
517
.
22.
Maia, N. M. M., Silva, J. M. M., and Sampaio, R. P. C., 1997, “Localization of Damage using Curvature of the Frequency-Response-Functions,” Proceedings of the 15th International Modal Analysis Conference, Society of Experimental Mechanics, 1, pp. 942–946.
23.
Zou, Y., Tong, L., and Steven, G. P., 1999, “Vibration-Based Model-Dependent Damage (Delamination) Identification and Health Monitoring for Composite Structures—A Review,” J. Sound Vib., awaiting publication, No. jsvi.1999.2624, 22 pages.
24.
Ratcliffe
,
C. P.
, and
Bagaria
,
W. J.
,
1998
, “
A Vibration Technique For Locating Delamination in a Composite Beam
,”
AIAA J.
,
36
, No.
6
, pp.
1074
1077
.
25.
Farrar
,
R. C.
, and
Jauregui
,
D. A.
,
1998
, “
Comparative Study of Damage Identification Algorithms Applied to a Bridge: I Experiment
,”
Smart Mater. Struct.
,
7
, No.
5
, pp.
704
719
.
26.
Matlab®, 1992–1999, The MathWorks, Inc., 3 Apple Hill Drive, Natick, MA 01760-2098.
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