A Study on the Influence Factors on Flexural and Thickness Modes in the Impact-echo Test

충격반향기법에서의 휨 모드 및 두께 모드의 영향인자에 대한 연구

Oh, Tae-Keun;Park, Jongl-Il;Byun, Yoseph;Lee, Young-Hak

  • Received : 2015.10.08
  • Accepted : 2015.11.03
  • Published : 2015.12.29


In this paper, various influence factors on the impact-echo test which is an effective method in characterizing defects such as such as the delamination in the concrete structures were studied. The side to thickness ratio(a/h), the relative position of impacting and sensing points over the delamination that have great effects on the flexural and impact-echo(thickness) modes were investigated and examined by the parametric finite element analysis. As a result, the flexural modes dominate in the case of a/h > 2 and the thickness mode was more evident when a/h < 2. With regard to the relative position of impact source and sensing point to the defect, the flexural modes dominate even when either the loading or sensing point was over the delamination defect. However, the thickness mode prevails when both the impacting and sensing points are over the solid region beyond the delamination area.


impact-echo test;flexural mode;impact-echo mode;thickness mode;side to thickness ratio;delamination


  1. Carino, N.J., Sansalone, M., Hsu, N.N. (1986) A Point Sourcepoint Receiver, Pulse-echo Technique for Flaw Detection in Concrete, ACI Journal, 832, pp.199-208.
  2. Mindlin, R.D. (1951) Influence of Rotary Inertia and Shear on Flexural Motions of Isotropic, Elastic Plates, ASME Journal of Applied Mechanics, 18, pp.31-38.
  3. Oh, T., Popovics, J.S., Ham, S., Shin S.W. (2012) Practical Finite Element Based Simulations of Nondestructive Evaluation Methods for Concrete, Computers & Structures, 98, pp.55-65
  4. Oh, T., Popovics, J.S., Sim, S. (2013) Analysis of Vibration for Regions above Rectangular Delamination Defects in Solids, Journal of Sound and Vibration, 332, pp.1766-1776.
  5. Sansalone, M.J., Streett,W.B. (1997) Impact-Echo: Nondestructive Evaluation of Concrete and Masonry, Bullbrier Press, 1997.
  6. Ventsel, E.S., Krauthammer, T. (2001) Thin Plates and Shells: Theory, Analysis, and Application, Marcel Dekker, Inc., New York
  7. Shin, S., Popovics, J.S., Oh, T. (2012) Cost Effective Aircoupled Impact-Echo Sensing for Rapid Detection of Delamination Damage in Concrete Structures, Advances in Structural Engineering, 15, pp.887-896,
  8. Zhu, J., Popovics, J.S. (2007) Imaging Concrete Structures Using Air-Coupled Impact-Echo, ASCE Journal of Engineering Mechanics, 133, pp.628-640.


Supported by : 한국연구재단