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Evaluating the Influence of Embedded Reinforcement on Concrete Resistivity Measurements

콘크리트 비저항 측정에서 주변 철근의 영향에 대한 실험적 연구

  • Lim, Young-Chul (Department of Architectural Engineering, Daegu Catholic University)
  • Received : 2023.07.10
  • Accepted : 2023.08.14
  • Published : 2023.10.20

Abstract

This research endeavors to explore the nuances in apparent resistivity readings in concrete specimens due to the proximity of embedded reinforcement. To systematically gauge this, concrete samples incorporating singular and paired rebars were meticulously crafted. These rebars were strategically positioned at intervals of 0.03m, 0.04m, and 0.05m from each specimen's midpoint. Subsequent resistivity assessments were conducted at 0.01m increments up to the predetermined rebar location for each sample. A consistent observation was the nadir in apparent resistivity manifesting at the rebar's epicenter. Notably, dual-rebar configurations registered lower resistivity values at this central juncture compared to their single-rebar counterparts. This metric underscores the palpable impact of surrounding reinforcement on resistivity readings. Further, as the spatial separation between rebars increased, the distinctness in their locational identification via resistivity became increasingly pronounced.

본 연구는 겉보기 비저항 측정에 포함되는 주변 철근의 영향을 파악하기 위해 단근과 복근을 매립한 콘크리트 실험체를 제작하였다. 실험체는 중심에서부터 0.03m, 0.04m, 0.05m의 위치에 단근 또는 복근을 배근하고, 겉보기 비저항 측정은 실험체별 정해진 위치까지 0.01m의 간격으로 실시하였다. 모든 실험체는 철근의 상부위치에서 겉보기 비저항이 최저치를 보였고 복근 실험체는 단근에 비해 배근 중심위치에서 낮은 측정치를 나타내며 주변 철근의 영향이 측정 결과에 반영되었음을 보였다. 또한 배근 간격이 넓을수록 철근의 위치가 명확하게 구분되는 것을 알 수 있었다.

Keywords

Acknowledgement

This work was supported by research grants from Daegu Catholic University in 2021.

References

  1. Wenner FA. Method of measuring earth resistivity. WA: Bulletin of the Bureau of Standards; 1916. p. 469-78.
  2. ASTM C876-09. Standard test method for corrosion potentials of uncoated reinforcing steel in concrete. West Conshohocken (PA): American Society for Testing and Materials. 2009. p. 1-7.
  3. Andrade C, Gonzales JA. Quantitative measurement of corrosion rate of reinforcing steels embedded in concrete using polarization resistance measurements. Werkstoffe und Korrosion. 1978 Aug;29(8):515-9. https://doi.org/10.1002/maco.19780290804
  4. Monteiro PJM, Morrison HF, Frangos W. Nondestructive measurement of corrosion state of reinforcing steel in concrete. Materials Journal. 1998 Nov;95(6):704-9. https://doi.org/10.14359/414
  5. Polder R. Test methods for on site measurement of resistivity of concrete - a RILEM TC-154 technical recommendation. Construction and Building Materials. 2001 Mar-Apr;15(2-3):125-31. https://doi.org/10.1016/S0950-0618(00)00061-1
  6. Hornbostel K, Larsen CK, Geiker MR. Relationship between concrete resistivity and corrosion rate - A literature review. Cement and Concrete Composites. 2013 May; 39:60-72. https://doi.org/10.1016/j.cemconcomp.2013.03.019
  7. Lim YC, Noguchi T, Lee HS. Mathematical modeling for corrosion environment estimation based on concrete resistivity measurement. ISIJ International. 2009 Jan;49(1):92-9. https://doi.org/10.2355/isijinternational.49.92
  8. Sassa K, Kanno T, Ashida Y. Geophysical exploration for construction and disaster prevention engineers. Tokyo (Japan): Morikita Press; 1999. p. 148-55.
  9. Gowers KR, Millard SG. Measurement of concrete resistivity for assessment of corrosion severity of steel using wenner technique. Materials Journal. 1999 Sep;96(5):536-41. https://doi.org/10.14359/655
  10. Lim YC. Experimental study on the effect of specimen size on electrical resistivity measurement. Journal of the Korea Institute for Structural Maintenance and Inspection. 2018 Nov;22(6):164-9. https://doi.org/10.11112/jksmi.2018.22.6.164