Jinping Hydropower Station Iv ~ Vi Of The Ridge Of High Slope Stability Evaluation

In Jinping First Stage Hydropower Station,stability problem of high rock slope is serious. The stability of the slope in the important positions ,which directly relates to the security of key project, is extremely significant problem for the engineering construction. On the basis of the item of Stability of slope and Supporting Countermeasure Investigation in key project of Jinping First Stage Hydropower Station, according to the in-site geological investigation and the exploration data, illustrated the geological environment situation, analyzed the high slope structure characteristic in deep fracture section of IV～VI ridge. Furthermore, the epigenetic reformation phenomena disclosed in the slope marble and sand-slate segment have been discussed respectively, and the deep embedded unloading body deformation assembled model have been summarized about on IV～VI ridge. Based on the recognized cause of formation mechanism of the high stress release and deep embedded unloading in the deep fracture, the mechanics response and evolvement mechanism of the deep embedded have been seriously analyzed, and the potential "creeping and shearing" instability model has been pointed out. Considering the rock mass quality of this deformation body incision borderline and slope toe shearing segment, the stability in position of three surveying line has been qualitatively investigated, the slope stability affected by the flood discharge in water-fog section has been discussed. Then, the stability of high slope has been reasonable investigated, and the corresponding supporting measure advice has been given. The detail content and acquired result are as following:1. Studied the basic engineering geological situation in IV～VI ridge, seriously analyzed the actual measurement stress environment characteristic, deduced the solution method of the space stress in profile stress ellipse, which can get the stress distribution character in No. IV profile.2. Studied the rock mass structure characteristic in IV～VI ridge, which mainly include the original, conformation and the epigenetic discontinuities. According to the classification, the controlling borderline of slope deformation affected by these structures has been illustrated, and the slope rock mass structure model has been established.3. According to the disclosed slope deformation damage phenomena, and the slope lithology combination and the slope body structure characteristic, analyzed the deformation damage mechanism and model, established the slope potential failure damage model. At last, the qualitative judgment of "the whole slope is stability, but security is lower" has been acquired for the present slope.4. The stability of the slope different saturation degree has analyzed in water-fog situation. Through calculation, the stability of some rock body outside of fault f₅ is lower and the whole slope stability can not satisfied the project demand. The slope body prevention water and drainage measure should be reinforced. In the same time, the slope entrance should be possibility lower, the rock mass disturbance should be reduced and supporting should be reinforced at the slope toe.