Study On Key Influence Factors In Slops Stability During Cut-Off Wall Construction In Deep Overburden Layer

As the expansion of China's infrastructure construction and scale, the depth of the bored piles and cut-off wall is increasing in the infrastructure projects, as well as the formation conditions are moreand more complex. With the implementation of the western development, the problem of the thick overburdens in the valley is increasingly prominent in water conservancy and hydropower construction. How can we ensure the forming slot's quality and slot stability when the cut-off wall is build in this complex formation condition, so it is very important to study the effect factors in the slot and trench wall stability in the process of making hole and groove. Due to the complexity and the hidden nature of underground conditions, It is difficult to have enough and detailed knowledge of ground conditions, especially the of and slurry infiltration process.Above all,it is necessary to specially research the process and mechanism of the to provide a theoretical basis for the measures of slurry protection and wall stability.Based on the above reason, effect factors to the trench wall's stability were researched fristly in the construction process of the cut-off wall in the thick overburdens, and specifically from the factors such as the slurry performance,ormation conditions,water table,groove section division and construction technology,construction machinery and ground orifice load which were analysised and summaried detailedly, then some effective measures were given to improve the stability of cut-off wall pointuing to the above factors,as well as some need researched works were proposed in the trench wall's stability of cut-off wall in thick overburdens.In order to determine the basic quantitative impact size of various factors on the stability of the slot.,cut-off wall slot of the HuangJin ping hydropower station in DaDu river as the research object, using the large-scale general-purpose finite element software Aabaqus and introduced of Duncan-Chang E-B constitutive model, excavation process of the cut-off wall's slot was simulated as well as the slot stress and displacement was calculated under the conditions of three different densities of slurry protection, the slot deformation characteristics was analysised under the condition of the slot excavation and different densities, and found that slurry density increasesis and trench wall lateral displacement reduced for the linear relationship.Considering the slurry precipitation, the displacements of the three kinds of slurry density variations and the slurry precipitation process on cut-off wall's slot was simulated. Using the calculated stress and displacement results, the impact of the slurry density variations and the slurry precipitation process on the deformation characteristics and stress distribution of cut-off wall's slot was analysised.