Stability Analysis And Characteristics Of Deformation Failure Of Sanhui Watr Plant Slop

Sanhui water plant landslide is located in the right bank of Ba river in Sichuan province. It has a flate tongue shape. The landslide is 100 m long and 190 m in width, with an average thickness of about 8.0m, the total volume is about 152000 m3.In September,2014,continuous heavy rainfall induced the collapse of soil mass in front of the slope. The house and retaining wall was craked. The ground settlement made the water supply pipeline cracked. Serious damage of landslide deformation resulting in 75 thousand and 100 people in sanhui town out of drinking water. Threat assets amounted to about 40 million yuan.Through the field survey, indoor physical mechanical test, the rock and soil mass transfer coefficient method and numerical simulation through FLAC3D (Fast Lagrangian Analysis of Continua), we can analyzed the stability of the slope and deformation failure mode. So as to put forward the control measures.Specific understanding is as follows:1.The landslide is composed of artificial backfill of building. It has a lithology of fragment stone of quaternary eluvial soil as the permeable layer; The bedrock is silty mudstone as the relative water-resisting layer. Continuous heavy rains caused heavy infiltration on to the bedrock surface, increasing the soil water content, and reducing the shear strength of rock and soil mass and weaken the anti-sliding ability of interface. Influenced by the incision of the river during high water level in flood season, soils slumping step by step, resulting in the occurrence of the deformation at postmedian of displaced body and the sliding failure.2.Using the limit equilibrium method to calculate the stability of landslide, the stability of the landslide is the worst in the condition of working condition three(deadweight+The water level is reduced from 260.66m to 245.0m).3.Through the numerical simulation of FLAC3D,the result shows that the landslide is under the condition of heavy rain is understable, and the deformation of the slope is larger than that of the vertical direction.4.Through the analysis of the characteristics and stability of landslide deformation,we put forward the comprehensive control measures of "drain dyke+retaining wall+slab-pile wall".