Abutment Downstream Slope Stability Studies And Numerical Simulation

With the western development strategy executing in China, all kinds of infrastructure constructions including railway, highway and water conservancy project, are built much more than ever before. In this process, because of the special geologic environment restriction in western region, a large numbers of the cutting excavation and the artificial slope are formed. Therefore, as an important problem that affects the engineering construction and safety, it is of significant to evaluate the slope stability, especially rock mass slope.The main research idea of this thesis is that by combining rock mass quality classification system and plasticity failure criterion, the fractured rock mechanics parameters are estimated, meanwhile, the tensor of permeability coefficient is researched in region of the reservoir. Then, based on the results, this thesis focuses on analyzing the stability of rock mass, which is near the dam in many cases, and studying the important influences of the mechanical characteristics and the rock slope stability for rock mass structure surface in these cases with numerical simulation method.The main research works in this thesis are listed as follow:1) The engineering geological conditions, the structure characteristics of rock mass, the rock quality classification system and the rock mechanics parameters are studied.2) The initial stress field of the rock mass slope is analyzed.3) The permeability coefficient tensor of rock mass is analyzed, and according to the different geological conditions, analysis the stability of the rock mass on the dam shoulder in the case of seepage and stress fields coupling, with the equivalent continuous medium anisotropy model and the continuous medium isotropy model.4) Using Overloading method to research the overloading capacity of rock mass and the deformation and failure process of the instability geological unites.5) 3D continuous model is set up with software FLAC to study the rock mass displacement and stress fields under three different load-case conditions, which are the dam foundation excavated condition, the reservoir water reserved condition and the rock mass reinforced condition. Then, in terms of the research results, the stability of the rock mass on the dam shoulder is evaluated.