Article Article
Detection and Assessment of Structural Flaws in Concrete Bridges with NDT Methods

Researchers investigated the applicability of various nondestructive testing (NDT) methods on full-scale concrete bridge structures, including ultrasonic pulse velocity tomography and the impact-echo method. The combination of the two methods enabled researchers to three-dimensionally evaluate material consistency and locate flaws or regions of deterioration within structural members with a new level of efficiency. Although research involving NDT methods has been conducted for many years, the use of NDT methods for primary investigation of full-scale structural elements is not typically performed. In this study, the investigation of bridge structures for flaws and damage resulted in the discovery of a previously undetected yet recurring form of damage, which led investigators to suspect a design flaw. The results of the ultrasonic pulse velocity tomography enabled researchers to assess the actual cause of the damage, which allowed the formulation of recommendations for the repair and redesign of the defective structural elements.

1. J. R. Leslie and W. J. Chessman. J. Amer. Concr. Inst. 21(1):17 (1949). 2. G. Washer. Reliability of Visual Inspection for Highway Bridges V. 1, FHWA Pub. FHWA-RD-01–020. Federal Highway Administration, McLean, VA. (2001). 3. M. Bergin, G. Mujtaba, and C. Ishee. Cement and Concrete: Trends and Challenges, p. 123. ACerS, Westerville, OH (2002). 4. C. Ferraro. Advanced Nondestructive Monitoring and Evaluation of Damage in Concrete Materials, M.E. Thesis, University of Florida, Gainesville, FL (2003). 5. D. E. Bray and D. McBride. Nondestructive Testing Techniques. Wiley and Sons, New York (1992). 6. J. Martin, K. J. Broughton, A. Giannopolous, M. S. A. Harsy, and M. C. Forde. NDT&E Int. 34:107 (2001). 7. A. Papoulis. Signal Analysis. McGraw-Hill, New York (1977). 8. T. R. Naik, V. M. Malhotra, and J. S. Popovics. Handbook on Nondestructive Testing of Concrete, 2nd ed. p. 8-1-8-14. CRC Press, New York (2004). 9. S. Popovics. The Analysis of Concrete Strength vs. Ultrasonic Strength Relationship: Back to Basics, ASNT Materials Evaluation. ANST, Columbus, OH. (2001). 10. A. J. Boyd and C. C. Ferraro. J. Mater. Civ. Eng. 17(2):153 (2005). 11. J. Krautkramer and H. Krautkramer. Ultrasonic Testing of Materials., 3rd ed. Springer-Verlag, New York (1983). 12. M. J. Sansalone and W. B. Strett. Impact-Echo Nondestructive Evaluation of Concrete and Masonry. Bullbrier Press, Ithaca, NY (1997). 13. M. G. Richardson. Fundamentals of Durable Reinforced Concrete. Spon Press, New York (2002). 14. H. Wiggenhauser, D. Streicher, C. Kohl, and J. Petz. Assessment of Post Tensioned Box Girder Bridges Applying Automated Non-destructive Testing Mehtods, TRB 85th Research Meeting, Report 06-1990, TRB, Washington, DC.
Usage Shares
Total Views
86 Page Views
Total Shares
0 Tweets
0 PDF Downloads
0 Facebook Shares
Total Usage