| In hydropower projects, Slope stability analysis is a hot topic and hard of Geotechnical engineering.Nowday, With the increasing in the number and the scale of projects, excaved a variety of the complex geological environmental conditions by people.All Steady state of the slope projects is relevant to the success and security of constructions.It will play as a restrictive role in the field and have an effect on the feasibility and economical efficiency.Then to a large extent,it will affect the investment and construction efficiency.Jinchuan Hydropower station is associated with a 112m high dam and 860 MW installed capacity. The geological condition, in the area of the dam, is complicated, with the steep slope and the weathered rock, which are important factor to control in slope shability. The dissertation is based on the analysis of the geological and environmental conditions, and analyzes the rock mass structural featuers of the slope in these dam areas, studies the instake slope stability as the core, evaluates the rock mass physical and rock mass structure characteristics in different part of the slope, by different methods, and analyzes of the investigation on the deformation-failure models of slope. The content and results are as follows:(1). Find out the intake slope is located in the Upper of Triassic-T3z2, T3z2(6) and T3z2(7) by ascertain, throught geological invesgation in the dam area. The steep fracture F19, which is exposed in the upstream of slope, is not very important to the stability of the slope.The inter-layer extrusion zone and dislocation zone, grow up long the structure of surface and unloading cracks and so on, are play a very important role in the slope stability.(2).Get the rock mechanics parameter of all kinds of rock mass discontinuity, by analyzing the structure surface of slope rock mass do the classification of the geolo- gical characteristics and analysis of rock surface structure, finding of Hoek-Brown failure criterion, access to the mechanical characteristic of solpe rock mass parameters, combining the experiment and the parameter of field experiment.(3).By applying the lasted findings about the quality classification of slope stability, the method of investigation and modified method of SMR and CSMR (China slope mass rating) have been put forward. The result shows that thin layers and mutual layers structure are the dominant,for weather effect, the surfacial rock mass quality is grade IV, in a whole, rock mass quality of slope can be described in grade Illa,Illb.Combined with various types of rock in the GB about the parameters of rock mass quality standards,got into rock mass of the shear and deformation paraments by the dicrete interpolation algorithm method.(4). Going on the structure of slope rock and the unloading rock study their characteristic, based on field investigation. Analyzed the deformation mode and deformation mechanism of the nuture slope, by using the geological structure and deformation model.(5). Searched the rock block that may combinated, using stereographic projection and three-dimensional geological model. Block mass theory has been utilized to given an slope stability analysis, then it was used to evaluate the local slope stability.(6). This paper have studied the sensitivity of part combination of block that were built-in stabilizer, Found the sensitivity factor on the stability of the slope block the influence of a certain degree of correlation. Affect the stability of the natural slope of the main block factor can be divided into two aspects of external and internal factors. Internal factors which play a leading role, including groundwater, earthquakes, block sliding surface, such as internal friction angle; external causes in the natural slope of the stability of block relatively weak impact, including human activities and surface water projects and so on.(7) The excavation slope stability than was in a close relationship, but also related to the excavation works and the volume of investment issues. Through field investi -gation, arrive at the slope than the natural slope, and finally through the largest na- tural slope and the slope than the relationship between the slope of the future to establish the best ratio of the excavation slope.(8). Connectivity rate is a reflection of the degree of random structure and connec- tivity to extend the status of an important parameter for evaluating the stability of rock engineering plays a key role in the control. In this paper, through the rock slope analo- g connectivity, the connectivity rate of rock mechanics and the relationship between strength parameters and calculate the strength parameters of rock mechanics. (9).Used the software Slide to evaluate the integral stability of the natural slope and excavated slope in various working conditions. Obtained Fs>1.4 in heaver rainstorm and earthquake condition, it indicated that the slope is stably.(10).Numerial simulation by using ANSYS is to give an analysis of displacement field and stress field of the slope.The analysis showed: when the slope is excavated, the slope along the face turn out unloding rebound from invagding, the slope will deforme, near 2230m to bottom; In the axial of the slope, the value of the largest shear strain deformation is 0.744mm. The result shows that the whole slope is stable, and the simulation result is coincided to the slope stability calculation.
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