Design And Parameterization Analysis Of Supporting Structure Of A Deep Foundation Pit

In this paper,a comprehensive building in Shenyang is used as the engineering background to study the two supporting forms of soil nail wall support and pile-anchor support.First,use the Lizheng deep foundation pit software to detect whether the deformation meets the safety requirements.After determining a reasonable plan,use PLAXIS to adjust the parameters of the two supporting methods,and analyze the changes of each parameter to the supporting structure Impact.In this way,we can find the critical point of monitoring alarm value and analyze the change curve of the parameter that tends to deformation and stability,and give reasonable suggestions for this kind of foundation pit engineering design.The results of the paper are as follows:(1)Comparing the characteristics and applicable conditions of various supporting forms in deep foundation pit supporting,the research focuses on the soil-nail wall supporting forms and pile-anchor supporting forms that are more suitable for the project.(2)For the deep foundation pit project of a comprehensive building in Shenyang,two types of pile anchors and soil nail walls that are more suitable for the project are selected by combining the geological conditions of the area where the project is located,considering the impact on the surrounding environment and the maturity of the construction technology.Using Lizheng software to select these two support schemes to design the foundation pit project,a safer and more economical design scheme was obtained,and then a comprehensive analysis was made from the two aspects of structural stability and the impact on the surrounding environment.Compare the advantages and disadvantages of the two design schemes.Under the premise of safety compliance,soil-nail wall support has less impact on the surrounding environment than pile-anchor support,but its stability is not as good as that of pile-anchor support.(3)Through the PLAXIS finite element software,a foundation pit profile model of a deep foundation pit project of a comprehensive building in Shenyang was established,and the influence of the change of the embedded length of the supporting pile and the change of the total length of the anchor rod on the pile-anchor supporting system was analyzed;The simulation results show that the horizontal and vertical displacements are relatively small,and they vary up and down the standard early warning critical value of foundation pit monitoring.In the part of soil-nailed wall support,firstly,the change of soil nail length was studied,and it was found that reducing this parameter still has little effect on the performance of the support structure,and it has not reached the level of damage,and the safety reserve is high.Therefore,the influence of changes in soil cohesion parameters on the performance of the soil-nailed wall support structure is analyzed.By comparing factors such as stress changes,displacement changes,and plastic point distribution,Found the critical point at which the change of cohesive force caused the soil to break down,Therefore,the change of cohesive force has a great impact on the safety of foundation pit engineering.The common factor that causes the change of cohesion is the change of moisture content.Therefore,during the construction of the foundation pit,the drainage design must be foolproof,and do not construct in the rainy season.