Instability Mode And Stability Analysis Of The Left Bank Head An Excavated Slope Of Jinping Hydropower Station

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. Baswed on discuss of the geologic environment of the high slope, and the engineering geological conditions of rock mass are carefully studied, and discussed break characteristic and excavate deformation of slope break mode and border terms in "shallow form department" and "dark department" of the head of dam. On the basis of these, the methods of 3D numerical simulation t are applied to analyze the deformation for the head of dam, and used the strength reduction method calculate stability of high slope in the head of dam, and the corresponding supporting measure advice has been given. The detail content and acquired result are as following:(1) According to the geological materials earlier stage and combined and construct in initial stage, has studied the rock mass structure characteristic in the head of dam, 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.(2) According to the left project geological condition of the slope in head of dam, combine the slope out of distortion at present existing, and excavated to the head of the dam slope the slope has carded on mechanism that destroys out of shape and mode analysis, have proposed the slope loses and destroys the mode and border potentially steadily.(3) Adopting the Flac3D simulate the response course under the condition in many steps about the head of dam. Through opposite side slope being different while excavating f42-9 the increment development characteristic contrast of the emergency, the course has reproduced the development situation that f42-9 emergency increment. Utilize the contrast of plasticity district of the "rock wall" outside f5, has analyzed the destruction situation to the "rock wall".(4) The stability under the operating mode has been calculated while using and converting two in natural and conservation storage to the slope in front of the dam into subtraction with the intensity, and compare with result of calculation of forefathers' balanced law of limit, appraise to the stability of the slope in the head of dam.(5) According to stability analysis of slope excavation above, Take the advice for excavation and propping up about the head of slope.