Long Term Automatic Displacement Monitoring of Large Scale Landslide Using GPS

Abstract

The authors introduce the automatic displacement monitoring system for the large-scale landslide using GPS and the long term monitoring result. In this case, the adoption of a long-term monitoring system with GPS was examined to observe the movement of an active landslide before and after the countermeasure construction. However, because the object landslide slope was northward, the applicability evaluation by a manual observation was carried out beforehand. Moreover, the characteristic of the GPS interferometric positioning to the displacement monitoring was understood by the experiments. The GPS monitoring system was composed of the one datum point at the stable ground and the five moving points in the landslide area, and began the continuous observation in October, 2003. The power supply of each station was a solar battery. At first, the cellular phones were used for online data transfer, afterwards they were changed to the wireless LAN lines.

This system was able to clarify the large displacements by the heavy rain in 2004, and calming down of landslide activity according to the countermeasure construction. In addition, the effectiveness of the tropospheric delay correction that used meteorological data was shown to the annual change that appeared to the vertical component of the displacements.