Stability Research And Risk Analysis Of Rock Slope Under The Action Of Seismic

The consequences of the instability and damage of the rock slope is usually very serious under the action of the earthquake, which will cause big losses of property and security to people and the country.Especially after the Wenchuan earthquake, the instability of the three gorges reservoir area under earthquake has been more and more got people’s attention.The impoundment of the three gorges dam often causes a lot of small earthquakes.The earthquakes have how much great influence on the long-term stability of the slope, that is also one of the focuses of the people.This paper combines with the national natural science fund project(41372356), and use the methods of theoretical analysis and numerical simulation to carry on a systematic in-depth research about the stability of rock slope under the action of the earthquake and risk.The main research work and achievements are as follows:① Based on two examples of slope, discuss the instability criterion of the strength subtraction conditions. Comparing several typical instability criterion to determine the key point displacement \ speed curve was used as convergence instability criterion to solve the dynamic safety factor.② Come to a conclusion: improving the slope strength parameters can improve the slope stability,and internal friction Angle affect slope stability more than the cohesive force; With the increase of the height and gradient of the slope stability safety factor get lower; Safety factor decreases with the increasing of seismic wave amplitude and frequency, and weak structural surface has a great influence on the slope stability.③ Carried out FLAC 3D numerical simulation of a large slope with weak structure surface in three gorges reservoir area,respectively to study the stability under static and the dynamic response and instability mechanism under seismic action. Analysis of the failure process of rock slope under seismic action, getting the conclusion that the weak surfaces of the rock slope have a great effect on dynamic characteristics. Analysis the slope stability safety factor under both static and seismic action with strength subtraction.④ According to the stability influent factors of rock slope, combined with the engineering geological conditions of the large domestic rock slope with weak structural surfaces is used to identify the risk factors of the slope, determine the indicators which influence the stability of slope is mainly including geology, geological structure, rock mass quality, the structure of the slope surface, slope structure, earthquakes, hydrology( rainfall and groundwater)conditions and human activities. According to the risk factors assessment to analysis the risk of slope. Comparing the risk analysis results with FLAC 3D simulation results, to proved that the safety factor of the slope under seismic action has exceeded safety margin, proving the scientific nature of the risk analysis of analytic hierarchy process(ahp).