Numerical Simulation On Creep Settlement Of Soft Clay

In the settlement analysis, the creep of soft soil should be considered;otherwisethe deviation may be occurred. This paper elaborates the creep theory of soil, theconstitutive relationship of the model is analyzed by the synthetically utilization ofvarious related theories and methods. Based upon the theoretical analysis, the finiteelement calculation program is established.Box-type foundation and semi-circular structure are harbor engineering structuresthat are suitable for the clay environments and that can be applied into breakwater orretain-wall. In this paper, with the Tianjin harbor breakwater serving as theengineering background, the settlement is calculated with the finite element analysissoftware package, PLAXIS.Firstly, a calculation of semi-circular structure is carried out with Soft-Soil-Creepmodel and Mohr-Coulomb model, and we compare the calculated results to themeasured results. It is validated that the creep characteristic should be considered inthe settlement calculation.Secondly, use two-dimension model to simulate the box-type structure withLinear-Elastic model, the deep soil with Mohr-Coulomb model, the shallow clay withSoft-Soil-Creep model, and the interface between structure and clay has been takenaccount. In addition, a practical project is analyzed, and the calculated results arecompared with the measured results. It is shown that settlement calculation byPLAXIS is reliable. Therefore, it is reasonable to predict the settlement of thebox-type foundation with this model.Finally, the influence factors of structure form, structure width, structure depthand parameter of soil are analyzed on 2-D FEM. It is shown that adopting theBox-type foundation structure, increasing the structure depth and the width, reducingthe structure weight and heightening the permeability coefficient will obviouslyquicken up the consolidation settlement and decreasing the finally settlement.Summarily, the trend of settlement can be depicted exactly with theSoft-Soil-Creep model and the FEM calculation program. Some relevant predictionsof the future creep tendency can also be made. By means of research on the influencefactors of the settlement, it can provide some references for the design andconstruction of the box-type foundation.