Publisher : The Computational Structural Engineering Institute
DOI : 10.7734/COSEIK.2015.28.6.659
Title & Authors
A Study on the Influence Factors on Flexural and Thickness Modes in the Impact-echo Test Oh, Tae-Keun; Park, Jongl-Il; Byun, Yoseph; Lee, Young-Hak;
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;
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