Research And Analysis Of Numerical Simulation For Different Ways Of Excavating Pit Deformation

In recent years, China’s modernization process is gradually speeding up, This hasgreatly promoted the rapid development of the Excavation engineering. In order tomeet the needs of high-rise buildings and the subway system, the scale of excavationis bigger, the depth of excavation is also deeper. At the same time, it also raised aseries of complex issues. The excavation Engineering where is located in thedowntown section of the city, the construction conditions is complex, it requires notonly to meet the building’s own security and stability, but also to ensure the safety ofthe nearby buildings during excavation. Nearly ten years at home and abroad theresearch of the deformation of inside and outside of the excavation has also achievedsignificant results, Generally considered flat-size effect, beam effects, pile insertiondepth, support stiffness and gusset have a significant effect on the foundationdeformation characteristics and stress distribution.During the excavation of the excavation, it is always that the former release stressin the soil, and set the support in the post. At this time, the difference of soil pressureinside and outside of the pit has generated, the Ground Wall has been partiallydeformed, The lateral movement ground Wall directly impacts to the subsidence ofthe soil around the pit outside, this is a relatively complex process. This thesis takesthe excavation engineering of Tianjin Water Tower as background, usingthree-dimensional finite difference software FLAC3D to simulate the differentprocesses of four kinds of step-by-step excavation pit layered, analysis the Settlementand deformation of the pit at the bottom, deformation Ground Wall and Pit andanalysis of the effect of pit space on Foundation Pit Deformation. This thesisdescribes FLAC3D model, the selection of the constitutive model parameter values,boundary conditions and initial conditions in detail, four excavation processsimulation results are analyzed, reaching the following conclusions: upliftdeformation of Pit bottom has a direct relationship with the excavation of theconstruction sequence, the deformation of first excavation portion is always greaterthan the part of the rear excavation, and it has Considerable difference of the everystep of the excavation of the scope and depth of the impact of different positions forthe foundation. The largest deformation of Ground Wall occurs in the position of the cross of the long side. The deformation of first excavation ground wall is alwaysgreater than the part of the rear excavation.