Frequency Spectrum Analysis of Impact-Echo Waveforms for T-Beams
Publication: Journal of Bridge Engineering
Volume 15, Issue 6
Abstract
Numerical and experimental studies were performed to assess the transient impact response of 11 T-beams with various dimensions and aspect ratios. Numerical modeling was performed using a three stage finite-element modeling procedure which included modal analysis, resonant analysis, and three-dimensional transient dynamic analysis. The response at impact locations on both the top centerline of the flange and the bottom centerline of the web was investigated. Physical models of three of the beams were constructed in the laboratory to determine the physical response of the beams when subjected to a transient impact and to verify the numerical results. Relationships between the fundamental frequencies and the frequencies of higher cross-sectional modes of vibration were established for the various aspect ratios. Shape factors were derived from the numerical and experimental results. The practical significance of the results is demonstrated for a project where impact-echo testing was used to nondestructively assess the condition of a decommissioned concrete T-shaped girder.
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Acknowledgments
This material is based on the work partially supported by the National Science Foundation under Grant No. NSFCMS 9875066. Dr. Dimitris Rizos is acknowledged for his helpful suggestions on the numerical modeling.
References
Aidoo, J. (2004). “Flexural retrofit of reinforced concrete bridge girders using three CFRP systems.” Ph.D. thesis, Univ. of South Carolina, Columbia, S.C.
Aidoo, J., Harries, K. A., and Petrou, M. F. (2006). “Full-scale experimental investigation of repair of reinforced concrete interstate bridge using CFRP materials.” J. Bridge Eng., 11, 350–358.
ASCE. (2005). Rep. Card for America’s Infrastructure, ⟨http://www.asce.org/reportcard/2005/index.cfm⟩ (Aug. 20, 2008).
Gassman, S. L., and Zein, A. S. (2008). “Change in impact-echo response during fatigue loading of concrete bridge T-girder.” ACI Mater. J., 105(4), 395–403.
Hill, M., McHugh, J., and Turner, J. D. (2000). “Cross-sectional modes in impact-echo testing of concrete structures.” J. Struct. Eng., 126(2), 228–234.
Lin, Y. (1992). “Impact response of bars with applications to concrete beams, columns and shafts.” Ph.D. thesis, Cornell Univ., Ithaca, N.Y.
Lin, Y., Lai, W., and Lin, K. (1998). “A numerical approach to determining the transient response of nonrectangular bars subjected to transverse elastic impact.” J. Acoust. Soc. Am., 103(3), 1468–1474.
Lin, Y., and Lin, K. (1997). “Transient impact response of bridge I-girders with and without flaws.” J. Bridge Eng., 2(4), 131–138.
Lin, Y., and Sansalone, M. (1992a). “Transient response of thick circular and square bars subjected to transverse elastic impact.” J. Acoust. Soc. Am., 91(2), 885–893.
Lin, Y., and Sansalone, M. (1992b). “Transient response of thick rectangular bars subjected to transverse elastic impact.” J. Acoust. Soc. Am., 91(5), 2674–2685.
Lin, Y., and Sansalone, M. (1992c). “Detecting flaws in concrete beams and columns using the impact-echo method.” ACI Mater. J., 89(4), 394–405.
NBI. (2007). “National bridge inventory.” ⟨http://www.fhwa.dot.gov/bridge/nbi.htm⟩ (Apr. 2, 2007).
Poston, R., and Sansalone, M. (1996). “Detecting crack in the beams and columns of a post-tensioned parking garage using the impact-echo method.” Innovations in nondestructive testing of concrete, American Concrete Institute, Farmington Hills, Mich.
Sansalone, M., and Streett, W. (1997). Impact-echo: Nondestructive Evaluation of concrete and masonry, Bullbrier Press, Ithaca, N.Y.
Zein, A. S. (2005). “Nondestructive evaluation of reinforced concrete T-shaped beams by frequency spectrum analysis of impact-echo waveforms.” Ph.D. thesis, Univ. of South Carolina, Columbia, S.C.
Zein, A. S., Gassman, S. L., and Harries, K. A. (2008). “Relationship between impact-echo response and structural behavior of retrofitted concrete girders during loading.” Materials Evaluation Journal American Society for Nondestructive Testing, 66(11), 1173–1181.
Information & Authors
Information
Published In
Journal of Bridge Engineering
Volume 15 • Issue 6 • November 2010
Pages: 705 - 714
Copyright
© 2010 ASCE.
History
Received: May 11, 2009
Accepted: Feb 22, 2010
Published online: Oct 15, 2010
Published in print: Nov 2010
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