Deformation Characteristics of Deep Excavations for Metro Stations in Shanghai Soft Soil Deposits

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  • 1.Department of Civil Engineering, Shanghai Jiaotong University, Shanghai 200030, China
    2.East China Architectural Design & Research Institude Co. , Ltd. , Shanghai 200002, China

Received date: 2007-12-15

  Online published: 2008-11-28

Abstract

The case histories of deformations due to the deep excavations for some metro stations in Shanghai soft soil deposits were presented and discussed. The statistics show that the ratio of the maximum lateral displacement of the retaining structures to the excavation depth ranges from 0.04% to 0.6%, and the mean value is about 0.3%. The deformation of the retaining structures develops a clearly deep-bulging profile as the excavations continue, and the maximum lateral displacement of the retaining structures usually appears between 1.5 m above the excavation surface and 7 m below the excavation surface. The ratio of the maximum surface ground settlement to the excavation depth lies between the range 0.05% to 0.7%, and the ratio of the maximum surface ground settlement to the maximum lateral displacement of retaining structures falls within the range 0.4 to 1. The construction method of cast-in-place piles combined with compaction grouting for cutting off groundwater is generally proved to be more effective in controlling deformation of deep excavations than diaphragm wall or SMW method.

Cite this article

DING Yong-chun, WANG Jian-hua, XU Zhong-hua, CHEN Jin-jian . Deformation Characteristics of Deep Excavations for Metro Stations in Shanghai Soft Soil Deposits[J]. Journal of Shanghai Jiaotong University, 2008 , 42(11) : 1871 -1875 . DOI: 10.16183/j.cnki.jsjtu.2008.11.026

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