| As gradually to the mountain developing of railway, transport, water conservancy, hydroelectric and other large-scale infrastructure projects, slope stability's problems under the complex conditions of mountain geological environment have become prominent. In order to make these infrastructure project well developing and fully displayed the engineering application function, it is the important meaning to make sure the high slope stability during the time of construction and operation.In this paper, Combining with the characteristic of the jialiega high slope in Pubugou Hydropower Station on Daduhe River, and basing on the strong geological investigation, the author mainly focuses on studying the characteristics of the slope mass structure planes, distribution, makes engineering geological zoning by the non-contact measurement techniques. According to the failure traces of slope during excavation, the mode of deformation is analyzed and the concept of deformation and failure mechanism model is established. A comprehensive analysis of monitoring data have been summed up slope deformation effect during excavation, and a simulation revives the characteristics of stress and displacement, makes stability check and re-evaluation by FLAC3D. The main conclusions of paper RE are follows:1. On the base of classification of rockmass structure planes, the author chooses the non-contact measurement methods for establishing method and work process of rapid investigation of structural plane, During the field investigation, the author firstly measures the excavating contour line of slope (excavation boundaries, platforms, etc.) with the help of laser range finder -GPS system, in the other hand the author measures cropline ofâ… ,â…¡structural planes of excavated surface one by one in the field. In the end the author acquires spatial positional relationship between the main structural planes and the slope, or among structural plane, at the same time the roughness and the filling and other information of structural planes are also be surveyed, and finally engineering geological sketch map of the slope is generated.2. The non-contact measurement technique is rapidly used to investigate structural planes of jialiega material slope. On the base of a lot of outdoor geological investigation and indoor statistics analyses, the author carries on the statistical analysis of its rockmass structure. The study results show that slope does not have these structural planes which can control stability of the whole slope, but there are mainly soft structural planes (I ,II)developing in the slope and structural planes of fracture type (III). Among I structural planes, dibasic veins constitute main framework of rockmass structure, and these II structural planes are composed of extruded planes or extruded zones. The overall rockmass structure is sub-block and the partial is crushed.3.Based on structural characteristics, slope weathering, the degree of unloading and engineering properties of rock and soil characteristics, The jiliega slope is divided intoâ…«districts. the rock mass structure of the upstream slope are cloddy~sub-lumpy structure. including I, II, XI-District; the central rock slope are sub-lumpy~ lumpy structure including III, IV, V, VIII, IX, X-District; the downstream slope show sub-lumpy~ lumpy structure, the mainly including VI, VII, XII-District.4. There are appearing many failure traces of slope during jialiega slope excavation, including the upstream slope'creep failures the middle and downstream slope, potential instability blocks, which mainly show superficial relaxation and unloading deformation. don't show the trend of the overall deformation and failure. The relationships analysis of time, displacement and hole depth show that the shallow slope form a relaxation unloading zone under the impact of excavation . with the completion of excavation, the trend of overall slope deformation is steady.5.On the base of establishment of conceptual model and evolution development process, the author uses FLAC3D numerical simulation method to calculate stability of the slope. The results show that rockmass generates deformation towards the outside for unloading springback after the excavation, but change of its stress state has little influence on the stability of the slope. At the same time tensile stress only appears at a certain range of surfacial rockmass and has a low value. Extension field of rockmass can not be found in the body of the slope, and displacement value of surface of the slope is 15 ~ 35mm. And the larger displacement only appears at the weak structure planes and lower edge of batter, and the largest displacement is 69mm. Simulation results show that after the excavation the whole slope will be not result in larger overall deformation and failure, but there is existence of local stability of slope which is controlled by weak structural planes.6.support parameters are putted forward in the base of structural characteristics and the main failure mode of instability, and combining with the geological conditions.â‘ Clean-up of dangerous rocks + bolt + linked to the drainage network + drainage;â‘¡Cleaning up dangerous rocks+ cable+lattice+ drainage;â‘¢Clean-up of dangerous rocks + pneumatically placed concrete + drainage.7.Based on studying characteristics of rock structure, according to the analysis failure phenomena, the monitoring data, and numerical simulation effect, which show that whole slope is steadily after excavation. Stability of the local blocks are poor it suggests strengthening the monitoring of slope stability, timely supporting, and ensuring successful implementation of excavation.
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