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Taiwan is an island where located at the Circum-Pacific Seismic Zone. In addition, the Philippine Sea Plate is pushed underneath the Eurasian Plate due to special geographical location. These may be attributed to the main reasons that have formed Taiwan as a mountainous country with complicated geological conditions. Moreover, the torrential rainfall accompanying typhoons frequently causes slope failures such as landslides and debris flows. The landslide of the dip slopes mainly occurs at the sedimentary rock layer of mountains and hills as observed at the west of Taiwan. Dip slopes of sedimentary rock are strongly affected by landslides due to natural disasters including torrential rainfall and earthquake. Moreover, some sedimentary rocks are alternated by different lithologies which contain sandstone and shale. Therefore water cannot infiltrate through the shale layer. As a result, the pore water pressure will increase and lead to the decrease in the shear strength between these layers. Finally, dip slopes will slide along the weaken zone as well as infiltration area.
In this study, we discussed the deformation and stress behavior of the dip slopes with two kinds of models. First of all, the bedding plane is parallel to the surface of the plane which will be simulated in the first model. The second model shows that the inclination of slope surface is smaller than bedding plane. In order to further realize the dip slope failure, the landslide of dip slope with different thicknesses of the layers can be observed and estimated by centrifugal modeling test and PFC3D simulation. Basically, the test is performed under the condition of the toe of slope daylight and soaked in water. Moreover, we have to consider the buoyancy at the toe of the slope so that the numerical model can be closer to real conditions. Based on the result of the centrifugal model tests, PFC3D model was first verified through comparing with centrifugal models, and then adopted to simulate and determine the mechanism of dip slope model with different gravity fields.
According to the results of the dip slope deformation, the stress paths showed different behaviors at each part of dip slope. In the first kind of model, the stress path showed stre | en_US |