dc.description.abstract |
Dip slope sliding is the most occurrence of slope disaster in Taiwan and the geology of Taiwan mostly consists of sedimentary rocks like sandstone and shale, both are very weak rocks. In recent years, the rainfall intensity enhancement and the influence time lengthened, had the severe influence on the geology of Taiwan. For instance, water easily seeps through aperture of rocks and reduces rock strength, or increases the pore water pressure thus decrease the shear resistance of soil. Due to above reasons, slope easily to produce slide and mudslide.
In this study, the discrete element method is used to simulate the sliding process and the deposition behavior of different types and scale slopes under different water level conditions, and discusses the effect of floating in numerical simulation. The numerical model is based on the centrifuge physical test model of Zeng, W. J. (2015) and Lin, Y. J. (2016)’s thesis.
The numerical models are carried out to modify the code of the weakening zone, and the results are compared with the physical test results. The aim is to integrate the parameters used by the three numerical models, including the dry friction coefficient and the wet friction coefficient which is reduced by water’s influence. After number of test, we decided to adopt the value of dry friction coefficient is 0.7 and the wet friction coefficient is 0.3, and using the discrete element method to simulate at different gravity. The analysis items include the sliding process of the slope, the stacking result, the displacement of each particle and the velocity of particle.
In this study, the sliding failure mode of the dip slope will be different according to the rock structure. The dip slpoe which is interbed layer and the angle of layer is 30 degrees is ”remove the toe of slope sliding mode”. The dip slpoe which is interbed layer and the angle of layer is 60 degrees is ”slope bulging sliding mode”. The dip slpoe which layer is alteration and the angle of layer is 60 degrees is ”rock fall mode”.
It is hoped that the simulation results of this study will provide to the disaster prevention center to reduce the disaster caused by sliding slop. | en_US |