Using Near-real-time Monitoring of Landslide Deformation to Interpret Hydrological Triggers in Jiudian Gorge Reservoir

Abstract

Near-real-time data with fine temporal resolution have been collected through using GPS from 105 to 130 m, and a Fast Moving Zone can be spatially identified from Main Deformation Zone, and the temporal evolution of the landslide consists of a progression in time with short periods of Fast Movement (FM) and longer periods of slower movement. The failure mode of landslide affected by rainfall is studied based on GPS monitoring data with PFC 2D being used to simulated the failure process of rain-induced landslide. Results indicate that three FMs can be identified from 105 to 130 m, and any rapid continuous drawdown of the reservoir water level from 130 to 105 m will definitely trigger FM. In addition, rapid continuous water rise tends to trigger FM from approximately 115 to 130 m while it will not trigger FMs unless there is a continuous drawdown phase before. Generally, there is a lag time between water level fluctuation and FMs.