The Simulation Of The Timbering Structure Between The Tie-Yue Station On Wuhan Subway Line 4

With the development of urban construction, there will be more and more basements in high-rise buildings, urban subway projects, and deep foundation pits engineering. At present, the most widely used timbering structures in deep foundation pits engineering are structural timbering and soil nailing. The design and calculation of deep foundation pits timbering involve structural engineering and geotechnical engineering and other disciplines. At the same time, the timbering structure is often formed through substeps of construction and timbering, so the calculation system is constantly changing.After the author have read a good many books and papers, this thesis is based on the real project of excavating and timbering foundation pits in the open cutting area between the Tiejicun Station and the Yuejiazui Station on Wuhan Subway Line 4, employs the large finite element analysis software PLAXIS oftern used in geotechnical engineering in simulating excavation and timbering plans of pile-group support between the Tiejicun Station and the Yuejiazui Station, and combines generalization and summarization. The following work has been mainly done.1. Documents about design and construction of deep foundation pits engineering in Wuhan have been looked up. Generally speaking, the engineering geologic and hydrogeologic conditions in Wuhan are relatively complicated. The middle and western parts of Wuchang District and Hanyang District belong to the mound-ridge topography, mainly composed of the sedimentation of the old cohesive soil, while Hankou District belongs to the second bottom of Changjiang River, mainly composed of the alluvial soil formed in the Holocene Epoch of the Quaternary Period, which is the weak foundation in Wuhan. This paper relies on the area between the Tiejicun Station and the Yuejiazui Station and analyses the parameters of layers of rocks, hydrogeology, and stratum physical-mechanics.2. The thesis employs the effective large finite element analysis software PLAXIS widely used in geotechnical engineering and underground engineering. It also systematically introduces the theory of analysis and calculation and the way of model building in PLAXIS. In general, PLAXIS can well simulate the interaction between the soil body and the structures. The software also provides a large sum of constitutive models and structural units.3. The thesis uses PLAXIS to conduct finite element simulation of excavation and timbering in the open cutting area between the Tiejicun Station and the Yuejiazui Station, getting the deformation and the internal force of the soil body under various operating modes, the internal force of the underground diaphragm wall, and the inherent stress of the roof bolt after excavation. Then, it analyzes the simulation result and compare it with the real design. The finite element simulation result and the analysis result offer references to the constructing and designing companies.4. Through the simulation analysis of the timbering structure in the open cutting area between the Tiejicun Station and the Yuejiazui Station on Wuhan Subway Line 4, the thesis obtains such valueable numerical values as the displacement and the internal force of the soil, the displacement and the internal force of the timbering structure, and gives detailed analyses and conclusions. At the same time, based on these statistics, it offers reference to the construction of the open cutting area between the Tiejicun Station and the Yuejiazui Station.