Array-measurement-based algorithm for detecting debonded regions between concrete matrix and steel reinforcing bars in concrete samples Conference Paper uri icon

abstract

  • The objective of this study is to develop an array measurement-based algorithm to identify debonded regions between the concrete matrix and steel reinforcing bars of concrete structures. In the proposed procedure, an impact hammer excites one end of a concrete sample and a tri-axial accelerometer is then used to measure the resulting vibration responses on both end surfaces of the sample. Then, a MUltiple SIgnal Classification (MUSIC) algorithm is used to locate the debonded regions as "passive" sources where reflective waves are generated. In order to suppress the effects of the direct waves generated from the excitation as well as the reflective waves from the boundaries at the ends of the sample that make it almost impossible to detect the subtle reflective waves from the debonded region, modified steering vectors are calculated from a finite element model of the sample including the effects of the direct and boundary-reflective waves. Then, the modified steering vectors are used to scan the concrete sample and calculate a 2-D MUSIC power map. By applying the proposed algorithm to both experimental and numerical data, it is shown that the proposed algorithm can be used to successfully detect the debonded regions of the concrete sample.

author list (cited authors)

  • Han, J. H., Kim, Y. J., Pagnotta, A., & Gardoni, P.

publication date

  • December 2012