Advanced finite element analysis of a complex deep excavation case history in Shanghai

Abstract

The construction of the North Square Shopping Center of the Shanghai South Railway Station is a large scale complex top-down deep excavation project. The excavation is adjacent to several current and newly planned Metro lines, and influenced by a neighboring Exchange Station excavation. The highly irregular geometry of this excavation greatly increases the complexity in 3D Finite Element modeling. The advanced numerical modeling described in this paper includes detailed structural and geotechnical behavior. Important features are considered in the analysis, e.g., 1) the small-strain stiffness of the soil, 2) the construction joints in the diaphragm wall, 3) the shrinkage in the concrete floor slabs and beams, 4) the complex construction sequences, and 5) the shape effect of the deep excavation. The numerical results agree well with the field data, and some valuable conclusions are generated.

Keywords

advanced finite element analysis / deep excavations / case history / small-strain stiffness

References

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Acknowledgements

The first author was sponsored by China Scholarship Council to study at the University of Oxford. The field data was provided by Dr. Zhonghua Xu who did the field measurement. The calculations were conducted on the Oxford Supercomputer Centre.

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2014 Higher Education Press and Springer-Verlag Berlin Heidelberg