(1. State Key Laboratory of Geomechanics and Geotechnical Engineering，Institute of Rock and Soil Mechanics，Chinese Academy of Sciences，Wuhan，Hubei 430071，China；2. Geotechnical and Structural Engineering Research Center，Shandong University，Jinan，Shandong 250061，China；3. Second Highway Consultants Co.，Ltd.，China Communications Construction Corporation，
Wuhan，Hubei 430056，China)
Abstract：It is difficult to choose an appropriate calculation method to determine the effective enclosure system in foundation pits design. This case study deals with the excavation of Jiangbei shield working shaft of Weisan road over-river tunnel in Nanjing，which is a typical deep working pit in soft soil strata. The spatial foundation plate method was used to analyze the deformation and stress condition of the structure of the shield working pit under dewatering outside the foundation pits. The m values of strata are obtained through back analysis；and the active and passive areas were judged by the DLOAD subroutine. The calculation results are consistent with the measured results；so the spatial foundation plate method with m values from back analysis can effectively predict the deformation and stress behavior of the enclosure structure. In order to further optimize the structure，three factors，i.e. thickness of diaphragm wall，size of supporting section and m value of soils within 5 m below the floor，are selected for orthogonal array experiment；and the main influencing factors of horizontal displacement of diaphragm wall and axial forces of bracings are obtained. The calculation method and the relevant results can provide references for similar engineering.
赵武胜1，陈卫忠1，2，袁克阔1，郑朋强1，袁敬强1，郭小红3，舒 恒3，拓勇飞3. 坑外降水条件下软土地层深大盾构工作井稳定性研究[J]. 岩石力学与工程学报, 2013, 32(3): 572-581.
ZHAO Wusheng1，CHEN Weizhong1，2，YUAN Kekuo1，ZHENG Pengqiang1，YUAN Jingqiang1，. STUDY OF STABILITY OF DEEP SHIELD WORKING SHAFT IN SOFT SOIL STRATA UNDER CONDITION OF DEWATERING OUTSIDE SHAFT. , 2013, 32(3): 572-581.
[1] 刘国彬，王卫东. 基坑工程手册[M]. 2版. 北京：中国建筑工业出版社，2009：149–155.(LIU Guobin，WANG Weidong. Handbook for excavation engineering[M]. 2nd ed. Beijing：China Architecture and Building Press，2009：149–155.(in Chinese))
[2] 罗耀武，凌道盛，陈云敏，等. 环形超深基坑围护结构受力变形特性分析[J]. 岩土力学，2011，32(2)：617–622.(LUO Yaowu，LING Daosheng，CHEN Yunmin，et al. Mechanical and deformation characteristics of enclosure structure for annular extra-deep excavation[J]. Rock and Soil Mechanics，2011，32(2)：617–622.(in Chinese))
[3] OU C Y，CHIOU D C. Three-dimensional finite element analysis of deep excavations[J]. Journal of Geotechnical Engineering，1996，122(5)：337–345.
[4] 尹盛斌，丁红岩. 软土基坑开挖引起的坑外地表沉降预测数值分析[J]. 岩土力学，2012，33(4)：1 210–1 216.(YIN Shengbin，DING Hongyan. Numerical analysis of estimation of ground surface settlement outside pit induced by soft-soil excavation[J]. Rock and Soil Mechanics，2012，33(4)：1 210–1 216.(in Chinese))
[5] 中华人民共和国行业标准编写组. JGJ120—99 建筑基坑支护设计规程[S]. 北京：中国建筑工业出版社，1999.(The Professional Standards Compilation Group of People?s Republic of China. JGJ120—99 Technical specification for retaining and protection of building foundation excavations[S]. Beijing：China Architecture and Building Press，1999.(in Chinese))
[6] 王 钊，邹维列，李广信. 挡土结构上的土压力和水压力[J]. 岩土力学，2003，24(2)：146–150.(WANG Zhao，ZOU Weilie，LI Guangxing. Earth pressure and water pressure on retaining structure[J]. Rock and Soil Mechanics，2003，24(2)：146–150.(in Chinese))
[7] 丛蔼森. 多层地基深基坑的渗流稳定问题探讨[J]. 岩石力学与工程学报，2009，28(10)：2 018–2 023.(CONG Aisen. Discussion on several issues of seepage stability of deep foundation pit in multilayered formation[J]. Chinese Journal of Rock Mechanics and Engineering，2009，28(10)：2 018–2 023.(in Chinese))
[8] 武朝军，陈锦剑，叶冠林，等. 苏州地铁车站基坑变形特性分析[J].岩土工程学报，2010，32(增1)：458–462.(WU Chaojun，CHEN Jinjian，YE Guanlin，et al. Deformation characteristics of foundation pits of subway stations in Suzhou[J]. Chinese Journal of Geotechnical Engineering，2010，32(Supp.1)：458–462.(in Chinese))
[9] 王旭军. 上海中心大厦裙房深大基坑工程围护墙变形分析[J]. 岩石力学与工程学报，2012，31(2)：421–431.(WANG Xujun. Analysis of retaining wall deformation for deep and big foundation pits of podium in Shanghai tower[J]. Chinese Journal of Rock Mechanics and Engineering，2012，31(2)：421–431.(in Chinese))
[10] 中华人民共和国国家标准编写组. GB 50007—2002 建筑地基基础设计规范[S]. 北京：中国建筑工业出版社，2002.(The National Standards Compilation Group of People?s Republic of China. GB 50007—2002 Code for design of building foundation[S]. Beijing：China Architecture and Building Press，2002.(in Chinese))
[11] 中华人民共和国国家标准编写组. GB 50010—2002 混凝土结构设计规范[S]. 北京：中国建筑工业出版社，2002.(The National Standards Compilation Group of People?s Republic of China. GB 50010—2002 Code for design of concrete structures[S]. Beijing：China Architecture and Building Press，2002.(in Chinese))
[12] 杨光华. 深基坑支护结构的实用计算方法及其应用[J]. 岩土力学，2004，25(12)：1 885–1 902.(YANG Guanghua. Practical calculation method of retaining structures for deep excavations and its application[J]. Rock and Soil Mechanics，2004，25(12)：1 885–1 902.(in Chinese))
[13] 南京市建设委员会. DGJ32/J 12—2005 南京地区建筑地基基础设计规范[S]. 北京：中国建筑工业出版社，2005.(Nanjing Municipal Commission of Housing and Urban-rural Development. DGJ32/J 12—2005 Code for design of building foundation in Nanjing area[S]. Beijing：China Architecture and Building Press，2005.(in Chinese))
[14] 贾善坡，陈卫忠，谭贤君，等. 大岗山水电站地下厂房区初始地应力场Nelder-Mead优化反演研究[J]. 岩土力学，2008，29(9)：2 341–2 349.(JIA Shanpo，CHEN Weizhong，TAN Xianjun，et al. Nelder- Mead algorithm for inversion analysis of in-situ stress field of underground powerhouse area of Dagangshan hydropower station[J]. Rock and Soil Mechanics，2008，29(9)：2 341–2 349.(in Chinese))
2013, Vol. 32 
