Applicability of time domain reflectometry for Yuhuangge landslide monitoring

Abstract

Yuhuangge (玉皇阁) landslide in Wushan (巫山), Chongqing (重庆), is one of the focal monitoring geological hazards in the Three Gorges Reservoir. Time domain reflectometry (TDR) and in-place inclinometers were arranged to monitor the deep deformation. Time domain reflectometry is based on transmitting an electromagnetic pulse into a coaxial cable grouted in rock or soil mass and watching for reflections of this transmission due to cable deformity induced by the ground deformation. Comparing the monitoring data of No. 5 Station, in the middle profile of the landslide, from June to December of 2008, the depth of slip surface determined by TDR is −33.58 m, which is consistent with the geological condition of the borehole nearby. The deformation curve trend of the TDR and inclinometer is similar, and it is uniform with the deformation caused by the Three Gorges Reservoir 175 m experimental impoundment. Further, TDR can monitor the tiny deformation accurately. Therefore, TDR is applicable to monitor the Yuhuangge landslide deep deformation and reflect the deformation characteristics well. It is significant to promote the application of TDR in landslide monitoring.

Keywords

time domain reflectometry / Yuhuangge landslide / applicability / deformation monitoring / fluctuation of reservoir level

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