Abstract: In anti-sliding pile designing for Reservoir landslide improvement, the reasonable pile position determination is very important, which effects the engineering safety and cost. Taking Zhanghuanhoumiao east landslide for example, based on the engineering geological condition investigation and with the GeoStudio software, according to the reservoir operation curve, considering 4 different pile positions, the numerical simulations were done. The results show that: ① When water level rising up, the displacement of front edge decreases, but the displacement of back edge increases. The maximum displacement of the front edge appears during water level drawing down and lowest water level. The maximum. displacement of the back edge appears during water level rising up and the highest water level. ② The reasonable pile position for the back, front and middle of the landslide are separately Ⅰ, Ⅱ pile positions. I pile is at the 175m, which residual pushing force is maximum the best pile is Ⅱ pile position, which is 130m from the shearing out point of landslide. At last, considering the influence of the water level fluctuation, the modified method of the safety factor for the anti-sliding pile design is presented, which will be important to the anti-sliding pile design for reservoir landslide.

Key words: running condition of reservoir, anti-sliding pile position, landslide stability, design safety factor