The Theory Of Spherical Cavity Expansion And Its Application

Spherical cavity expansion, solution and simulation of soil deformation caused by static pile, measure of reducing influence caused by pile driving on the engineering environment have been studied in this paper.Soil is assumed to be a homogeneous, isotropic and elastic–prefect plastic material. A dilation angle is used to consider soil dilation. Soft coefficient is used to consider soil softening. By using the principle of the elastic– plastic theory, the analytical solution of the spherical cavity expansion including the ultimate pressure, the stress field and displacement field, plastic scope was obtained.On the study of the solution and simulation of the soil deformation caused by static piling, a model of spherical cavity expansion at the pile toe while piling is introduced. The problem of static piling in half– space medium has been creatively solved by a source– source imaging technique and Boussinesq's solution and Mindlin's solution. The solutions of a stress field, a displacement field, a pore pressure field and the variation of soil strength caused by pile installation.The author has put forward some effective measures to prevent or reduce the damages to the engineering environment. The author also analyses the different effect caused by different measure. The sheltering effect of pile driving is also discussed. The author has describe environment monitoring technology relating to the effect of pile driving, and has proposed some operating index.