Abstract
Reservoir filling can affect the landslide stability and cause the landslide deformation within the reservoir area. In this paper, a physical model test and a series of numerical analyses were combined to investigate the landslide deformation and stability under reservoir filling. The surface deformation, deep displacement, and pore water pressure were recorded during the physical model test. In the model test, the increasing period of the pore water pressure inside the landslide is proposed to be a critical period for the landslide subjected to the reservoir filling. During this period, large landslide deformation occurred. The numerical analyses show that a greater factor of safety (FOS) appeared under a higher water level rising rate or a lower permeability coefficient during the water level rising stage when other variables are fixed, due to the domination of the reservoir buttressing effect which can increase the landslide resistance. During the reservoir maintaining stage, the reservoir water infiltrated into the landslide continuously to cause the matric suction dissipation and pore water pressure increase, which reduced the landslide shear strength and then decreased the landslide stability.
Highlights
The Three Gorges Dam is the largest hydropower project in the world
The physical model test and numerical simulation were combined to study the deformation and stability of a landslide subjected to the reservoir filling
During the water level maintaining stage, less time is needed for the groundwater equilibrium under a high permeability coefficient
Summary
The Three Gorges Dam is the largest hydropower project in the world. The reservoir impoundment affects the landslide stability within the reservoir area, and more than 5300 landslides have been identified in the Three Gorges Reservoir area [1, 2]. The drawdown of reservoir water is a critical condition for destabilizing landslides [3]. Observations that landslide deformation is associated with the reservoir drawdown have been widely reported [4,5,6,7,8]. The dynamic seepage pressure pointing outwards the slope is a crucial factor for deforming landslides after water level drawdown [9,10,11], especially when the landslide material has a low hydraulic conductivity [12]. The Qianjiangping landslide in the Three Gorges Reservoir area occurred shortly after the water level reached 135 m, which claimed 24 lives and made 1200 people homeless [16]. It was found that 49% of the landslides occurred during the reservoir filling stage. Riemer [18] examined 60 publications regarding landslides in reservoir areas and found that 85% of landslides were induced during the reservoir filling or 2 years after the filling
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
