Numerical Simulation Analysis Of Time-effect Durring The Deep Foundation Pit Construction

In process of deep excavation in soft ground, Excavation of palisade structure displacement, structures of internal and external will change with the time of pit excavation construction, and Cree perfects are detectable. Meanwhile, the unloading induced by the excavation leads to the dissipation of excess Pore water. The two results are embodyed by time effect. And the internal force ,displacement of the foundation pit etc. are relate to the shape and size of the foundation pit, and they change with the deep and location of the foundation pit, which is called Space effect.According to the time effect and space effect of the foundation. This article study that how variation of foundation pit happen with the time effect. This article use FLAC as the tool, This soft is able to simulate the coupled effect of consolidation and creep interaction between soi1 and structure,and the complicated Procedure of staged excavation. This program uses the explicit calculation model, the seepage calculation method is more reasonable, especially for large deformation calculation model. Introducing linear elastic constitutive relation, more- coulomb constitutive relation, and considering the nonlinear elastic stress path. Because of the slip between the soil and the wall, we may set a thin contact elements, which is closer to reality.We use this program to analyses of deep foundation pit precipitation, Super static pore pressure during excavation of the lift, the surface subsidence behand the wall, the soil uplift of the bottom of the foundation pit and so on. And considering the effect of consolidation and consolidation and rheological properties of foundation pit when coupling effects.In the end, combined with tianjin hejihuangpu deep excavation engineering as an examples. simulation by actual data, research foundation under different conditions change trend(for example: Precipitation and excavation), which we used to direct the actual engineering design. This program can be described in soft soil area excavation of time effect. In addition, the effect of excavation time analyzed prediction.