Analysis On Influence Of Seepage In Deep Pit

The seepage of groundwater is one cause of destroying deep foundation pit. It is significative and essential that the article research the mechanism of seepage's effecting deep foundation pit.Firstly, the mechanics performances of pit's soil, including distribution of stress and instance of strain, will be varied because of the existent of seepage; on the other hand, the distortion of soil will change channels of the movement of groundwater and then effect mechanics performances of seepage, which is called the issue of coupling the hydraulic of the seepage field with the stress field. Secondly, the losing and abrupt gush of soil are the usual forms of the soil distortion, which, in some extent, relate with the drop of waterpower. So, it's essential of studying the seepage field.The article researches the mechanism of seepage and studies the mechanism of coupling the seepage field and stress field through finite element simulation, and then compiles the programs with FORTRAN. On the base of principle of quality conservation and momentum conservation, the article establishes the domination formulations of seepage field. And then scattering the elements, it forms the format of the formulations above with Galerkin methods. By comparing with the formulations of elasticity mechanics, we can find that they are similar, so we can unify the forms when we compile program of the FEM. The article establishes the formulation about coupling the seepage field and the stress field through combining the formulations of the two fields. The nonlinearity of soil should take into account, so the article adopts "initial-stress" finite element approach to resolve the coupling formulation.At last, we use the theories above to research the seepage field, stress field and strain field during excavation, which possesses theory and practice signification in some extent.