| The study of slope stability under earthquake load has great implications. This thesis is focused on dynamic analysis of response of jointed rock slope to earthquake by using numerical modeling, the theory of load-unload response ratio and the nonlinear system method. The primary purpose is to solve the problem of combination of deformation analysis and stability evaluation in this research field.More than 100 years have passed since scientists and engineers began to study the stability of slopes. As this is a difficult task involving many disciplines and subjects, many key problems remain unsolved now. In this thesis, a review on the status of slope stability research is firstly presented. Issues are summed up. It found that combination of deformation analysis and stability evaluation for slopes is still the focus in the study field of slopes stability. There are many methods to calculate for deformation or stability, but they can not solve both deformation analysis and stability evaluation, such as pseudo-static method can simply evaluate stability of slopes but can not analyze the deformation of slopes; however Newmark sliding block analysis and numerical methods can calculate the permanent displacements of slopes but can not evaluate stability of slopes. It is mainly because different existed in the basis of theory. So it is difficult to combine deformation analysis with stability evaluation. Only new idea based on the process of slope failure can do that.Focused on issues above, much research works are performed in this thesis. At first, the spatial distribution feature of landslide hazard in china and the primary influencing dynamic stability of slopes are analyzed. The effect of set-out violent slide and progressive failure during earthquakes are presented. Then dynamic responses (displacement, velocity, acceleration) to earthquakes of uniform slopes are calculated by finite element method. Suggested by the study of earthquake prediction, the theory of load-unload response ratio (LURR) is introduced into the analysis of slope dynamic stability. It is verified that the LURR theory is application to this analysis by comparing with the MTS test and numerical calculation results achieved byYinxiangchu.Second, based on the basic theory of LURR, the load-unload response ratio model of slope are established. Take displacement, velocity and acceleration of slopes as response parameters, the load-unload response features of slopes under the affection of earthquake are described. And the affection of frequency of earthquake wave and phasic lag of displacement response are discussed by input three kinds of sine wave.Third, chooses the jointed rock slope as study target. By means of the discrete element method and the load-unload response model, features of deformation are analyzed. Based on their nonlinear characters and the reconstruction theory of phase space, it is proved that the evolution of slope is a chaotic process and the stability failure of slopes is essentially a bifurcation. It is proved that the saddle point is intrinsic attribute of system during its evolution when 4 sets of ideal sine wave and 3 sets of observed seismic wave are input to the slope. A concept of load-unload response degree is suggested. By this concept, the dynamic stability of slopes is determined, and deformation analysis and stability evaluation are well combined.At last, taking the right bank of the Majiayan reservoir as an example, a dynamic analysis is performed using the methods suggested in this thesis. Comparing the calculation results with those of three-dimensional finite element analysis, it is testified that the methods presented in this work are reasonable and correct. The new contributions of this thesis can be summarized as follows:(1) For the first time, this study applies the LURR theory to dynamic stability analysis of slopes, and establishes the load-unload response model of slopes. Answer the stability of slopes under dynamic input.(2) According to the nonlinear theory, the turn of slope system st...
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