Consolidation Mechanism And Nonlinear Numerical Analysis Of Soft Foundation With Vacuum-surcharge Preloading

Dredger fill foundation has low bearing capacity,large deformation,long consolidation time and other characteristics.The principles of consolidation and constitutive models help us understand the settlement rules.It is of significant practical importance to use ABAQUS to simulate the actual works of consolidation that can help us expect the settlement,deformation and pore pressure.The main work includes the following aspects:1.Based on the various ways of foundation reinforcement,it can be concluded that the method of vacuum-surcharge preloading is the most suitable and economical way for a large and depth soft clay foundation.The different strengthening mechanism were analyzed by effective stress principle and strength growth principle.2.The finite element model is based on the theory of Biot consolidation and the theory of modify Cam-Clay model.Using ABAQUS program to simulate the Terzaghi consolidation.The result is compared to the theoretical calculation result.The sand drains is transformed into sand foundation wall that considering well resistance,role of seepage and daub.The problem of the parameter selection about plastic drain board is discussed,and it is applied in the simulation of ABAQUS successfully.3.The data of modify Cam-Clay model was transformed into ABAQUS parameters in an engineering example.The load step,the time step,boundary conditions and stress balanced approach are analyzed particularly.4.With ABAQUS program,the factors of influence on settlement with vacuum-surcharge preloading is analyzed by the quantitative analysis of different distance and depth of plastic drainage board,the degree of vacuum,the magnitude of preloading and etc.