Collapse occurs during the excavation of a highway tunnel, and hence it is urgent to use geophysical method to detect other potential collapse areas. In view of the large difference of the terrain, the lush surface vegetation and the low resistivity of the surrounding rock, the authors selected the opposing coils transient electromagnetic method (OCTEM) as the equipment of this method which is relatively light and it has high resolution in reflecting the resistivity. Firstly, OCTEM response of underground collapses buried in conductive host was calculated, and the results theoretically proved that OCTEM was sensitive to underground resistivity and had high resolution, and then the OCTEM detection result was compared with the high-density electrometer detection result. It is proved that they correspond well, and both reflect the known collapse area. It is shown that OCTEM can be applied to rapid detection of collapse area in the highway tunnel under construction.
刘杰, 段炜, 王俊, 刘成, 戴国强. 等值反磁通瞬变电磁法在公路隧道塌陷区的探测应用[J]. 物探与化探, 2020, 44(6): 1470-1475.
LIU Jie, DUAN Wei, WANG Jun, LIU Cheng, DAI Guo-Qiang. The application of opposing coils transient electromagnetic method to the detection of underground collapse in highway tunnel under construction. Geophysical and Geochemical Exploration, 2020, 44(6): 1470-1475.
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