< Back to TEA-21 Completed Projects List
Concrete Evaluation Using Guided Waves
Project Number: A479, A495
Principal Investigator: Richard Finno
1. Project Abstract
2. Final Research Report
3. Publications
Project Abstract:
The purpose of this project is to develop methods to non-destructively evaluate the condition of concrete components of bridges, including columns, foundation elements and bridge piers by extending guided wave theory to flexural wave propagation in concrete columns and piles and to longitudinal and flexural waves in embedded plates (representing cast-in-place and soil mixed walls). A theory based on guided waves, describing the relation between frequency and group velocity of frequency-controlled excitations, has been developed for longitudinal wave propagation in cylindrical members to allow higher frequencies to be used to non-destructively evaluate such members, and, consequently, to identify smaller defects than possible with conventional techniques.
Many times one cannot access the top of a cylindrical element, but can only place instruments on the sides of the member, for example, at a pier for a bent of a bridge. When energy is added at the side of a column, one can generate flexural waves that have different propagation characteristics than longitudinal waves. Flexural waves in general are dispersive, i.e., their propagation velocity depends on frequency. Furthermore, the displacements associated with flexural waves also depend on frequency. Hence to use these waves to non-destructively evaluate a member, one must have the dispersion relation in hand to know how fast the waves travel and to locate the optimal position of a transducer to measure the response. Whereas the theoretical solution for flexural wave propagation in a concrete cylinder has been published, to use the information, one must numerically evaluate the solution to find propagation velocities and displacements. The solutions for embedded cylinders that represent concrete piles, has not been published for flexural wave propagation. The numerical solutions for both longitudinal and flexural wave propagation for embedded plates do not exist.
Hence to extend non-destructive techniques to allow application of higher frequencies, and hence create the ability to sense smaller defects, this project plans to develop numerical solutions for flexural wave propagation in cylinders and plates and for longitudinal propagation in plates. In addition to the numerical work, experimental verification of the numerical solutions will be made on prototype cylinders and plates.
Final Research Report:
Concrete Evaluation Using Guided Waves
Years 5-6 Final Report
A479, A495
Concrete Evaluation Using Guided Waves: Parts I & II (PDF, 7 mb)
Publications:
Year |
Title |
Author(s) |
File |
| 2005 | Guided waves in embedded concrete piles. Journal of Geotechnical and Geoenvironmental Engineering, 131 (1), 11-19. | Richard J. Finno, Hsiao-chou Chao | |
| 2004 | "Theoretical Evaluation of Embedded Plate-Like and Solid Cylindrical Concrete Structures with Guided Waves", PhD Dissertation, December 2004 | Helsin Wang | |
| 2002 | "Non-destructive Evaluation of Drilled Shafts at the Amherst NGES Test Section", Proceedings, International Deep Foundation Congress, ASCE, Orlando, FL., February, 2002 | Richard J. Finno, Hsiao-Chao Chou, S. L. Gassman, P. Zhou | N/A |
| 2000 | "Anomaly Detection in Drilled Shafts", Proceedings, National Geotechnical Experimentation Sites, Geotechnical Special Publication 93, ASCE, J. Benoit and A.J. Lutenegger, eds. , 2000, p. 221-234 | S. L. Gassman, Richard J. Finno | N/A |
| 2000 | "Cutoff Frequencies for Impulse Response Tests of Existing Foundations", Journal of Performance of Constructed Facilities, ASCE, Vol. 14, No. 1, pp. 11-21, February, 2000 | S. L. Gassman, Richard J. Finno | |
| 2000 | "Nondestructive Evaluation of Drilled Shafts at the Central Artery/Tunnel Project", Proceedings, Structural Materials Technology IV: an NDT Conference, Atlantic City, New Jersey, pp. 81-88, February 2000 | Richard J. Finno, Hsiao-Chao Chou | N/A |
| N/A | "Guided Wave Interpretation of Surface Reflection Techniques for Deep Foundations", Italian Geotechnical Journal | Richard J. Finno, J. S. Popovics, A. A. Hanifah, W. L. Kath, Hsiao-Chao Chou, Y. H. Hu | N/A |
| N/A | "Frequency Equation for Cylindrical Piles Embedded in Soil", Journal of Engineering Mechanics, ASCE | Richard J. Finno, J. S. Popovics, W. L. Kath, A. A. Hanifah | N/A |
| N/A | "A System for Guided Wave Tests on Deep Foundations", (to be submitted to the Geotechnical Testing Journal, ASTM) | Richard J. Finno, Hsiao-Chao Chou | N/A |
| N/A | "Use of the Universal Mode Frequency to Evaluate Shear Wave Velocity in Cylindrical Concrete Members", (to be submitted to the ACI Materials Journal) | Richard J. Finno, Hsiao-Chao Chou | N/A |
| N/A | "Guided Wave Evaluation of Concrete Cylinders", (to be submitted to the ACI Materials Journal) | Richard J. Finno, Hsiao-Chao Chou | N/A |
