Numerical Simulation Research On Deep Foundation Dtch Of Baiyang Building In Chengdu

In recent years, Chinese construction and municipal engineering have been developing rapidly with the development of economic environment. In the city, because of the high cost of land, the use of underground space has become an important direction. The underground space and facilities, including the basement level and multi-storey buildings, underground shopping street, underground garage, subway stations, and other forms of cross-river tunnel. Construction of the underground space and facilities, the first step is the large-scale excavation, therefore, as a guarantee of deep excavation of the deep excavation technology has been continuously developing.This text research on the earth pressure,bracing scheme and the parameter of the bracing structure relying on this deep foundation ditch engineering.The main results gained can be summed up as follows:(1)Analyse the existed shortage of the thickness weighted simplified method about the physieal meehanieal parameter of the soil horizons first and then starting from the angle of equivalent internal force of the bracing strueture, extraet the simplified ealculation Prineiple and method which is corresponding to the physieal mechanical parameter of the soil horizons and equivalent internal force of the bracing strueture.Comparing with the results which are ealculated according to the traditional earth pressure ealculation method, it indicate that the simplificd method extraeted in this text is more appropriate.(2)Aim at the diffieulty of looking for inflection point when using equivalent beam method to analyse the pile anehor strueture in soil horizons with high cohesive strength, extract mapping method and equivalent bending moment method to ensure the location and value of the bracing.The effect is yerified preferably in this foundation ditch engineering.(3) By the use of finite difference software FLAC3D, a three-dimensional simulation of the entire process of excavation and support of deep excavation is accomplished.The behavior of retaining structure is analyzed, and the deformation laws of deep excavation is studied in six cases. Monitoring results and calculation results of the largest horizontal displacement of retaining pile are basically the same.(4) The spatial effect of deep excavation is analyzed by FLAG, the result shows that:the spatial distribution of the bracing structure displacements and the axial force of the steel support has strong spatial effect:Spatial effect of the corner is strong.and the spatial effect of The central section weakens.the result show that the calculation of three-dimensional analysis of deep excavation is an effective means to study spatial effect.