Analysis of Small-Loop Electromagnetic Signals to Detect Subsurface Anomaly Zones

Applied Sciences

Chan-Hee Lee¹  Dong-Hyuk Kim²  Jin-Hoon Jeong²  Ki-Hyo Choi² 

[1] Department of Airports, Korea Engineering Consultants Corp., 21, Sangil-ro 6-gil, Gangdong-gu, Seoul 05288, Korea;Department of Civil Engineering, Inha University, 100 Inha-ro, Michuhol-gu, Incheon 22212, Korea;

关键词: small-loop electromagnetic exploration;    cavities;    ground softening;    underground facilities;    electrical resistivity;    electrical conductivity;   

DOI  :  10.3390/app10186329

来源: DOAJ

【 摘 要 】

Recently, sinkholes have significantly increased in urban areas as a result of subsurface cavities and ground softening. In this study, a small-loop electromagnetic survey was conducted in a testbed where anomaly zones comprised of cavities, areas of ground softening, and underground facilities were simulated in the ground under road pavement using the CMD Mini Explorer. The equipment was only able to measure the electrical resistivity (ER) at three depths. As, occasionally, the equipment was unable to detect the anomaly zones using the ER measured at those three depths, survey measurements were taken at three heights to collect the ER at seven depths using the superposition method. The result shows that the anomaly zones can be detected qualitatively by visually observing the contour map of the ER. In addition, another method for detecting anomaly zones in the ground statistically using a box plot and the relative standard deviation was employed in this study. Consequently, the position and depth of the cavities, areas of ground softening, and underground facilities in the testbed can also be determined quantitatively.

【 授权许可】

Unknown