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http://dx.doi.org/10.14481/jkges.2021.22.11.31

Development of Buried Type TDR Module for Leak Detection from Buried Pipe  

Hong, Wontaek (Department of Civil & Environmental Engineering, Gachon University)
Publication Information
Journal of the Korean GEO-environmental Society / v.22, no.11, 2021 , pp. 31-37 More about this Journal
Abstract
To prevent accidents due to the cavities and loosened layers formed due to water leakage from the deteriorated buried pipes, evaluation of the changes in water contents around the buried pipes is required. As a method to evaluate the water contents of the soils, time domain reflectometry (TDR) system can be adopted. However, slender electrodes used in standard TDR probe may be damaged when buried in the ground. Thus, in this study, buried type TDR module was developed for the evaluation of the water contents with maintaining required shape of the electrodes in the ground. The TDR module is composed of three electrodes connected to the core conductor and outer conductor and a casing to prevent deformation and maintain alignment of the electrodes in the ground. For the verification of TDR waveforms measured using the TDR module, comparative analysis was conducted with the TDR waveforms measured using the standard TDR probe, and the relationship between the volumetric water content of the soils and the travel time of the guided electromagnetic wave was constructed. In addition, a model test was conducted to test the applicability of the buried type TDR module, and the experimental result shows that the TDR module clearly evaluates the changes in volumetric water contents due to the leakage from the modeled buried pipe. Therefore, the buried type TDR module may be effectively used for the health monitoring of the buried pipe and the evaluation of the water contents around the pipes buried in the urban pavements.
Keywords
Buried pipe; Electromagnetic wave; Leakage; Time domain reflectometry (TDR); Volumetric water content;
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  • Reference
1 ASTM D6565 (2005), Standard Test Method for Determination of Water (Moisture) Content of Soil by the Time-Domain Reflectometry (TDR) Method, ASTM International, West Conshohocken, PA, 2005.
2 Benedetto, A. and Pensa, S. (2007), Indirect diagnosis of pavement structural damages using surface GPR reflection techniques, Journal of Applied Geophysics, Vol. 62, pp. 107~123.   DOI
3 Brinkmann, R., Parise, M. and Dye, D. (2008), Sinkhole distribution in a rapidly developing urban environment: Hillsborough County, Tampa Bay area, Florida, Engineering Geology, Vol. 99, No. 3, pp. 169~184.   DOI
4 Diefenderfer, B., Galal, K. and Mokarem, D. W. (2005), Effect of subsurface drainage on the structural capacity of flexible pavement, VTRC 05-R35, Project, Vol. 66818, p. 29.
5 Hyun, S. Y. (2017), A Study on characteristics of ground-penetrating radar signals for detection of buried pipes, The Journal of Korean Institute of Electromagnetic Engineering and Science, Vol. 28, No. 1, pp. 42~48.   DOI
6 Kelly, E. J. (1999), Soil moisture effects in pavement systems, M. Sc. thesis, Ohio University, Athens.
7 Hyun, S. Y. (2016), Laboratory experiments of a ground-penetrating radar for detecting subsurface cavities in the vicinity of a buried pipe, The Journal of Korean Institute of Electromagnetic Engineering and Science, Vol. 27 No. 2, pp. 131~137.   DOI
8 Topp, G. C., Davis, J. L. and Annan, A. P. (1980), Electromagnetic determination of soil water content: Measurements in coaxial transmission lines, Water Resources Research, Vol. 16. No. 3, pp. 574~582.   DOI
9 Noborio, K., McInnes, K. J. and Heilman, J. L. (1996), Measurements of soil water content, heat capacity, and thermal conductivity with a single TDR probe, Soil Science, Vol. 161, No. 1, pp. 22~28.   DOI
10 Subedi, S., Kawamoto, K., Karunarathna, A. K., Moldrup, P., Wollesen de Jonge, L. and Komatsu, T. (2013), Mini tensiometer-time domain reflectometry coil probe for measuring soil water retention properties, Soil Science Society of America Journal, Vol. 77, No. 5, pp. 1517~1528.   DOI
11 Wang, P., Hu, Z., Zhao, Y. and Li, X. (2016), Experimental study of soil compaction effects on GPR signals, Journal of Applied Geophysics, Vol. 126, pp. 128~137.   DOI
12 Jung, J. and Lee, I. (2021), Image-based location tracking and mapping to improve accuracy of underground facility location information, Journal of the Korean Society of Civil Engineers, Vol. 69, No. 8, pp. 27~33.
13 Vaz, C. M. P. and Hopmans, J. W. (2001), Simultaneous measurement of soil penetration resistance and water content with a combined penetrometer-TDR moisture probe, Soil Science Society of America Journal, Vol. 65, No. 1, pp. 4~12.   DOI
14 Kim, Y., Kim, J. B., Kim, D. and Han, J. G. (2017), Experimental study on generating mechanism of the ground subsidence of due to damaged waterssupply pipe, Journal of Korean Geosynthetics Society, Vol. 16, No. 2, pp. 139~148.