The Foundation Pit Supporting Design And Numerical Simulation Analysis Of Changchun Wansheng Building

With the process of our urbanization progressing constantly after entering into21th century, there are more and more tall buildings, extra-high buildings appear. Cityunderground shopping mall, underground parking, urban rail transportation andmunicipal underground facilities can be seen everywhere. Because of the pitexcavating largely and deeply, it makes the deep foundation pit engineering progressgreatly, many new forms of foundation pit supporting appear constantly, theories forsupporting design much more mature, and the construction technology progresscontinuously. It is vigilant that there are many accidents happen sometimes, due to thescale is larger, the surroundings are more complex, and therefore, it is an ancient andeternal subject for deep foundation pit engineering. It raises many new subjects in thestructure supporting, groundwater controlling, foundation pit monitoring, informationconstruction, and environmental protection etc.The content selects a suitable foundation pit supporting way to take calculationfor design. And make the two dimensional finite element numerical simulations,according to the actual situation of Changchun Wansheng buildings. The main contentis as follows:(1)Analyze the common foundation pit supporting structure of the applicablecondition, according to the specific situation of Changchun Wansheng buildingfoundation pit engineering, grasp the principle of selection of the foundation pitsupporting structure, select two schemes of the Prestressed anchor composite soil nailwall supporting scheme and pile anchor supporting.(2)Take the calculations for each the supporting scheme, and use the limitequilibrium method for composite soil nailing wall calculation, equivalent beammethod for pile anchor supporting scheme, in terms of internal force calculation.(3)Check the stability of the two kinds of foundation pit supporting scheme byusing Lizheng deep foundation pit structural calculation software, according to thecalculation results to determine two kinds of supporting structure design scheme.(4)Set up two kinds of support structure of two dimensional finite elementsimulation model respectively, basing on MIDAS/GTS analysis software, and definition the stage of construction, analyze two supporting scheme in the horizontaldisplacements, the vertical displacement of soils and internal force of retainingstructure in the simulation results, then take the conclusion about the generalregulation. Comparing with the two kinds of supporting schemes simulation results, itis revealed that the pile anchor supporting scheme can control the soil displacementmore strictly, but the two scheme simulation results are both under the control in thesecurity range.(5) The subject uses the pile anchor supporting scheme to compare the horizontaldisplacements of the soil and surface subsidence monitoring data with MIDAS/GTSsoftware simulation data, then draws the deformation curve. The drawing shows thatthe both are in good agreement; it is proved that the supporting schemes are rational,and the numerical simulation results are reliable.(6)It is known that, according to the former research, the composite soil nail wallsupport scheme can satisfy the supporting structure and soils around security andstability, and the pile anchor supporting scheme is more economical.