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Nondestructive Evaluation of In-Isolation Pile Shaft Integrity by Wigner-Ville Distribution

Published online by Cambridge University Press:  05 May 2011

S.-H. Ni*
Affiliation:
Department of Civil Engineering, National Cheng Kung University, Tainan, Taiwan 70101, R.O.C.
J.-J. Charng*
Affiliation:
Department of Civil Engineering, National Cheng Kung University, Tainan, Taiwan 70101, R.O.C.
K.-F. Lo*
Affiliation:
Department of Civil Engineering, National Cheng Kung University, Tainan, Taiwan 70101, R.O.C.
*
*Professor
**Associate Professor
***Graduate student
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Abstract

The Wigner-Ville Distribution is a new numerical analysis tool for signal process technique in the time-frequency domain and it can offer assistance and enhance signal characteristics for better resolution both easily and quickly. Time-frequency transform can describe how a spectrum of signals changes with time owing to defects and boundary conditions. In this study, five single pre-cast concrete piles have been tested and evaluated by both sonic echo method and Wigner-Ville distribution (WVD). The appropriateness of time-frequency domain analysis is discussed. Furthermore, two difficult problems in nondestructive evaluation problems are discussed and solved: the first one is with a pile with slight defect, whose necking area percentage is less than 10%, and the other is a pile with multiple defects. The results show that WVD can not only recognize the characteristics easily, but also locate the defects more clearly than the traditional pile integrity testing method.

Type
Articles
Copyright
Copyright © The Society of Theoretical and Applied Mechanics, R.O.C. 2007

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References

1.Davis, A. G. and Dunn, C. S., “From Theory to Field Experience with Non-Destructive Vibration Testing of Piles,” Proc. Ins. of Civil Engineering, Part 2, London, 57, pp. 571593(1974).Google Scholar
2.Olson, L. D. and Wright, C. C., “Nondestructive Testing of Deep Foundations with Sonic Methods,” Proc., Found. Engrg. Congr.: Current Principles andPract., 2, ASCE, pp. 11731183 (1989).Google Scholar
3.Hartung, M., Meier, K. and Rodatz, W., “Integrity Testing on Model Pile,” The 4th Int. Conference on the Application of Stress-Wave Theory to Piles, Netherlands, Balkema, Rotterdam, pp. 265271 (1992).Google Scholar
4.Liao, S. T., Nondestructureive Testing of Piles, PhD. Dissertation, Department of Civil Engineering, University of Texas, Austin, Texas, U.S.A. (1994).Google Scholar
5.Qian, S. and Chen, D., “Joint Time-Frequency Analysis,” IEEE Signal Processing Magazine, pp. 5267 (1999).CrossRefGoogle Scholar
6.Chiang, C. H. and Cheng, C. C., “Detecting Rebars and Tubes Inside Concrete Slabs Using Continuous Wavelet Transform of Elastic Waves,” Journal of Mechanics, 20, pp. 297302 (2004).CrossRefGoogle Scholar
7.Wigner, E. P., “On the Quantum Correction for Thermodynamic Equilibrium,” Phys. Re., 40, pp. 749759 (1932).CrossRefGoogle Scholar
8.Ville, J., “Théorie Et Applications De La Notion De Signal Analytique,” Câbles et Transmissions, 2A, pp. 6174 (1948).Google Scholar
9.Cunningham, G. S. and Williams, W. J., “Kernel Decompositions of Time-Frequency Distribution,” IEEE Trans. Signal Process, 42, pp. 14251442 (1994).CrossRefGoogle Scholar
10.Mallat, S. G., A Theory for Multiresolution Signal Decomposition: The Wavelet Representation, MS-CIS-87-22, GRASP, Lab. 102, Univ. of Pennsylvania, May (1987).Google Scholar
11.Serutti, S., Bianchi, A. M. and Mainardi, L. T., “Advanced Spectral Methods for Detecting Dynamic Behavior,” Autonomic and Neuroscience: Basic and Clinical, 90, pp. 312 (2001).CrossRefGoogle Scholar
12.Zou, J. and Chen, J., “A Comparative Study on Time-Frequency Feature of Cracked Rotor by Wigner-Ville Distribution and Wavelet Transform,” Journal of Intact and Vibration, 276, pp. 111 (2004).Google Scholar
13.Qian, S., Introduction to Time-Frequency and Wavelet Transforms, Prentice Hall PTR Prentice-Hall, Inc., pp. 101126(2002)Google Scholar