Study On The Stability Of Xiahongyan Talus Slope Of Baihetan Hydropower Station

Baihetan hydropower station will be constructed with in Baihetan valley which links Qiaojia country of Yunan province and Ningnan county of Sichuan province,which is the second level station in Panzhihua and Yibin which installed capacity of hydropower plant is 14004MW,It is another planned ten millions of kilowatts project after Three Gorges and Xiluodu Water Conservancy Project in China. Studies have shown that there develops a debris flow–Dazhai gully on the right bank of the station, on the left and right bank of which there will decorate diversion tunnel and water diversion system of station, and upstream cofferdam is close to the ditch mouth of the gully,so the general layout of station will be controlled by the debris folw, now construction units has made a series of processing measures on the debris flow,such as landslide dam and so on.Xiahongyan talus slope locates on the right bank of Dazhai gully, which currently has appeared the deformation and cracking and the anterior slope has crowded the channel of Dazhaigou by appearing"tongue",so its stability is closely related with the engineering construction layout, instability will directly endanger landslide dam of dazhai gully, intake slope and outgoing line well,So the stability of Xia Hongyan accumulation is of great significance to the proposed dam and ancillary facilities of the waterpower.Based on researches on the geological environment of the construction area, the composition and the structure of the accumulation,this paper studies the genetic mechanism of the accumulation , at the same time, according to physiognomy signs of deformation and characteristics of the different components,we have disparted the different engineering geology on the basis of in-depth analysis of the basic characteristic of accumulation, on the basis of this,we discuss the causes of the talus slope and deformation mechanism of the future, mainly focus on the trigger factors which impact on the stability of the talus slope; In order to analyz the situation of groundwater activities and the influence degree of stability,the seepage simulation mainly aims at the changes of underground water level in the storm conditions;finally we evaluate on the local stability as well as the whole accumulation (distract) by using the limit equilibrium method and finite difference method, basing on the calculated results, this paper proposes corresponding prevention and disposal measures and suggestions based on the way of damage, the scale of damage and influence of the project that may be caused.