Study On The Reinforcement Effect Of Anti Slide Pile With Reservoir Water Level Fluctuation

The Majiapo landslide in Ziyang County is located on the east bank of Ankang Reservoir.The landslide threatens the operation of the reservoir,the safety of life and property of the residents around the landslide.Through investigation and analysis,the treatment plan of the landslide has been proposed by studying the destruction form and material composition of the landslide.In order to study the reinforcement effect of anti slide piles under the conditions of water level fluctuations,the physical and mechanical indices of rock and soil in the saturatedwater loss cycle were obtained using laboratory tests,and numerical simulations were performed using the finite element analysis software MIDAS/GTS.The main research results are as follows:(1)The Majiapo landslide is a medium-sized landslide.The geotechnical properties of the rock and soil are weakening.As the water level of the reservoir changes and rainfall infiltrates,a certain amount of deformation and damage has occurred.(2)Combining with the deformation and material composition of landslide,a comprehensive treatment plan for “slope drainage + anti slide pile” was proposed.One row of anti slide piles was placed in the front of the slope and the existing drainage facilities on the slope were used to set up the drainage ditch.(3)It can be seen from the laboratory tests that the main component of the sliding body and the sliding belt is strong weathering phyllite.Under the condition of saturated-loss of water,the physical and mechanical parameters are degraded,showing a trend which has a rapid decline followed by a slow decline.(4)Through the numerical simulation,it can be seen that when the slope body is not reinforced by anti slide piles and the water level of the reservoir is decreasing,the stability of the slope body is lower than that under the static and rising conditions of the water level due to the presence of osmotic pressure in the slope body.(5)After anti slide piles are installed in the front of the slope body,the stability of the slope body has been greatly improved,indicating that the design of the anti slide piles is reasonable.With the increase in the number of water level changes,the mechanical properties of the rock and soil bodies in the slopes will follow decreased,leading to a decline in stability,the rate of decline is slower after the first.It shows that under the condition of water level circulation,the reinforcement effect of anti slide piles is weakening.Therefore,there should be enough considerations in the design.