Open Cut Method In Underground Engineering Approaching Constructionof The Theretical Analysis And Numerical Simulation

Open cut method in underground engineering construction will disturb the surrounding soil. Not only by the disturbance of soil deformation, but also affects the supporting structure and approaching construction deformation. In this paper, from monitoring data, soil excavation of the secondary stress theory and numerical simulation study underground engineering excavation method construction of supporting structure, surrounding soils and approaching construction of the deformation.Collecting a large amount of monitoring data in the process of construction. Monitoring data including: the surface subsidence, soldier pile lateral displacement, the displacement of deep soil, near building settlement, etc., Explore the influence of excavation on the surrounding environment. Analysis of monitoring data curve of the shape, causes, fitting prediction formula, for regard to the same method of construction for the region. According to supporting structure deformation data, summarizes the deformation modes of retaining structure mainly has the following five kinds: around wall toe rotation, around the wall deformation of the rotation, translation, parabolic and hyperbolic of basic deformation modes, and made up by basic mode superposition model, fitting the corresponding prediction formula, explore the deformation law; According to the monitoring data of surface subsidence, found that the different support way of the different surface subsidence deformation, according to the single row pile, double-row piles, single row pile and inner support three different supporting method, fitting the corresponding prediction formula of surface settlement.Analysis and arrange the approaching construction foundation settlement data, according to the laws of the subsidence curve, deduce the prediction formula of the foundation under a convex.In the soil exists primary stress state before the construction, which lead to the soil secondary stress state. Using loewen plane rectangular gap of the displacement formula to calculate the underground engineering excavation surface subsidence, the resilience value at the bottom and side horizontal displacement of the three deformation. Using the calculated value compared with the monitoring data of the cutting section. The results show that resilience calculated value and the numerical solution fitting is good, the surface settlement calculation value and monitoring in the distance is close and the tendency is to close gradually, side horizontal displacement calculated value and the monitoring value differ big can’t meet the needs of the use.According to the practical engineering of underground structure and the approaching 4 layers of concrete frame for corresponding prototype. Using the finite element software MIDAS/NX to found numerical model. According to the project site image and text record data, determine the construction process, then determine the numerical simulation of each construction stage, which can accurate simulation of the underground engineering site construction conditions. Focus on the analysis of the construction of supporting pile, soil, existing buildings of deformation. Verify the numerical solution and the theoretical solution, monitoring value, ioon the basis of the theory, by means of numerical modeling analysis, based on monitoring data of direction, analysis of the deformation of the impact of Open cut method in underground engineering.