Bottom Of The Pit Overall Stability And Deformation Of Soft Soil

In excavation, it is a critical problem that the combined effects of pit bottom soft soil on the excavation of global stability and deformation. This paper introduces the basic theories and calculation methods in excavation on global stability and deformation at present. It Introduces the characteristic of all kinds of finite element theory techniques and illuminates in particular the key technique of the finite element model, element type and so on in analyzing the problem. The finite element software ABAQUS is used in excavation model. It deals with soils by geological stratification, at the same time stepped excavation and stepwise supporting analysis technique is adopted. The Lizheng Deep Excavation Supporting Software F-SPW5.3(The Chinese software for excavation at present)is used to analyze the global stability and deformation Of excavation. The soft soil thickness, soft soil excavation depth and soft soil physical-mechanical properties is studied for the model analysis. The slope gradient for excavation, the effects of soil nail wall, cement mixing piles and piles in row is researched. The critical pit excavation engineering is analyzed, the results are good with the numerical analysis's. This paper presents the concept of"critical depth"and"limit thickness"for soft soil. It gets the results of non circular arc in global stability analysis of pit engineering. The conclusion is good for design and construction of pit engineering in soft soil area.