Study on the Deformation Mechanism of Reservoir Landslides Considering Rheological Properties of the Slip Zone Soil: A Case Study in the Three Gorges Reservoir Region

Reservoir water level fluctuation is one of the main extrinsic factors that could change the stress field in landslides, as well as the mechanical strength of geomaterials, hence affecting the deformation and stability of landslides. The largest reservoir landslide in the Three Gorges Reservoir area was selected for a case study. The impact of reservoir water level fluctuation is represented by the dynamic change in the underground seepage field and was thereby analyzed with numerical modeling. The deformation behavior considering the rheological properties of the slip zone soil was studied. The sudden change in the displacement–time curve was selected as the failure criterion for the investigated landslide. The evolution process of the accelerated deformation stage was divided into slow acceleration, fast acceleration, and rapid acceleration stages. The Huangtupo landslide is characterized by a retrogressive landslide and is currently in the creep deformation stage; the deformation mechanism and deformation characteristics are closely related to the reservoir water level fluctuation. Research was carried out by means of field investigation, in situ monitoring, and numerical simulation to provide a true and reliable result for stability evaluation.

Study on Relationship between Deformation of Reservoir Water Level Fluctuation Change of the Shuping Landslide

The change of reservoir water level fluctuation has an important influence on the landslide deformation. In this paper, taking Zigui County of the Three Gorges Reservoir Shuping landslide as an example, based on the deformation and water level of reservoir deformation related analysis of landslide, summarizes the general rule by reservoir water level variation effect on deformation of landslide, which can provide some reference for the monitoring and analysis of landslide similar.

Bankside Stability Analysis under the Actions of Rainfall and Reservoir Water Level Fluctuation

It has been accepted that the rainfall and the reservoir water level fluctuation plays an important role in the stability of the reservoir bankside. However, at present, there has not been suitable simplification method for the project application to calculate and appraise. Therefore, based on the Boussinesq’s differential equation of unsteady-seepage and boundary condition, and Laplace’s transform, the curvilinear equation of phreatic line in landslide mass is deduced under the rainfall and the reservoir water level fluctuation conditions, and a simplified formula which can be used in the project is gained by the polynomial fitting. Meanwhile, it holds together the transmission coefficient method to write programs about the bankside stability analysis in the paper. With the Er-Liban landslide of the three Gorges Reservoir area for the computation model, this paper use the program to analyze the change rule and stability of the phreatic line under the reservoir water level fluctuation and rainfall condition.