Numerical Analysis Of High-rise Building Deep Foundation And Retaining Structure Optimization Design Study

The computation methods and pertinent problems of the support works of deep excavation are analyzed and summarized in detail in this paper, which are the references to the FEM analysis of the multi-staged excavation.With the consideration of soil-structure interaction, process of multi-staged construction, A plane FEM model for simulating excavation is established, which is used to analyze and discuss the behaviors of excavation. The model adopts eight-nodes isoparametric quadrilateral element, Drucker-Prager ideal Elastic-Plastic stress-strain model and the contact element, which is used to simulate the interface between the wall and soil. Accordingly, A flow chart about the arithmetic of contact is introduced in this paper.The plane FEM model analyzes the behaviors of deep excavation, and the step-excavation effect during excavation is studied such as the horizontal displacement of the retaining wall, ground settlement and the forces in struts. The influences on the behaviors of excavation are discussed due to the stiffness (width) of the retaining wall, the embedded length of the wall and the strut stiffness.Based on the deformation control, optimization design method of the retaining structure is proposed. This method considers the interaction of soil-structure and the whole harmony of the retaining structure and inner-support structure. First the method combines optimization design method with FEM. The results of analysis prove that this method is feasible.