Study On Deformation Characteristic And Its Calculation Mode Application Of Deep Foundation Pit Supported With Piles And Anchors

Deep foundation pit engineering put forward new challenges to the technical persons in area,depth,construction difficulty,and the complexity of the surrounding environment,at present.If foundation pit collapse or lost stability,the consequences will be unimaginable.Many of failure cases demonstrated a huge loss of property and personnel.The deformation of foundation pit is the main factor of causing the foundation pit failure.Therefore,the deformation characteristics generated by construction of foundation pit attracted attentions of engineering and technical personnel,also the relevant technical and scientific problems has become the research hostpot and the difficulty of the content.Numerical simulation software FLAC and LIZHENG are used respectively to build calculating model of deep foundation pits and analyze the deformation which showed in the construction of foundation pit under no suppot,supported by cantilever pile and by pile and anchor.The step number of excavation of foundation pit,the size of overweighted and the form of foundation pit retaining structure have important impact on the evolution of deformation characteristic.The horizontal displacement on the top of the foundation pit and the curve of vertical settlement deformation respectively are drawed,on the basis of measured deformation data.Then,the deformation characteristics of gradual convergence in deep foundation pit supported by pile and anchor are summarized.With the help of the exponential model and grey prediction model,the prediction model of foundation pit vertical displacement is obtained.Based on the deformation characteristics of the foundation pit under non-limit state,a kind of foundation pit horizontal displacement formulas is derived based on optimizational combination which provide new thoughts for calculation model of foundation pit deformation.The project application shows that the two models provide a new method for foundation pit deformation calculation,and the application result is good.