The Character And The Application Of The Canyon's Stress Filed Of Changheba Hydroelectric Power Station

On the bases of the research about the basic geological condition,the structure ofthe slope and the sign of the crack deformation, the essay analysis the stress field ofdifferent altitude of the dam area by stress relief—recovery method. we alsoinvestigate the development of the high stress character, combined the testes result ofthe aperture distortion method and the hydrofracturing method, we studied thedistribution of the stress field of the canyon by The modeling of 2-D and 3-D finiteelement analysis. Furthermore, we also discussed the application in this field.(1) We tested the secondary stress field of different altitude by the stress relief—recovery method, and we inversion analysis the test result by the 2-D finite elementanalysis, we finally get the result of the "hump" character of the rock stress field.(2) By the results of the aperture distortion method and the hydrofracturingmethod and some geological phenomenons, we analysised the quantification of thecanyon's stress field, so that we can divided the stress field into stress decline zone,stress increase zone,stress fluctuated zone and natural stress zone. the horizontaldepth of the stress increase zone is 40m～120m, the horizontal depth of natural stresszone is in 360m. the direction of the max stress is NWW～EW。(3) With the The modeling of 3-D finite element analysis, we inversion analysisedthe formation and the developing disciplinarian of the canyon's stress field,.now, thecanyon's stress field is the combination of the structural stress and the naturalstress. the direction of the min stress is vertical to the surface of the rock mass, whilethe max is parallel to the surface, the hign stress focus is located in the bottom of thecanyon.(4) I worte a program about the ANSYS—FLAC3D conversion by VB. thecombination the ansys and flac3d make the modeling and calculation possible.(5) Based on the connection between the canyon's stress field and the dischargeof the slope, we discussed the classification of the slope's stress, the result fit thequalitative classification by the test achievement of wave velocity,springback andslope stress field. So finally, we can classify the discharge zone of the rock mass of the slope.(6) Based on the result of the research, we can classify the rock mass of theslope. after the comparison of the result of the qualitative judgement and CSMRmethod, we can draw the conclusion that, the classification of the rock mass of theshoulder of the dam isⅡ～Ⅲ, theⅡ,Ⅲlevel is about 76.7% of the left shore of theslope, theⅣlevel of the rock is in the surface of the slope, between the entrance to50 depth in the adit.