Collapse of deep excavations for metro lines in soft clay

WANG Li-zhong; LIU Ya-jing; LONG Fan; HONG Yi

doi:10.11779/CJGE202009004

Volume 42 Issue 9

Turn off MathJax

Article Contents

Abstract

References

Chinese Journal of Geotechnical Engineering > 2020 > 42(9): 1603-1611. > DOI: 10.11779/CJGE202009004

WANG Li-zhong, LIU Ya-jing, LONG Fan, HONG Yi. Collapse of deep excavations for metro lines in soft clay[J]. Chinese Journal of Geotechnical Engineering, 2020, 42(9): 1603-1611. DOI: 10.11779/CJGE202009004

Citation:

PDF (2242 KB)

Collapse of deep excavations for metro lines in soft clay

WANG Li-zhong^{1, 2,},
LIU Ya-jing^{1, 2},
LONG Fan³,
HONG Yi^{1, 2, ,}

1.
College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310058, China
2.
Key Laboratory of Offshore Geotechnics and Material of Zhejiang Province, Zhejiang University, Hangzhou 310058, China
3.
Wuhan Municipal Engineering Design and Research Institute Co., Ltd., Wuhan 430023, China

More Information

Received Date: December 05, 2019
Available Online: December 07, 2022

Graphical Abstract

Abstract

Abstract

In recent decades, numerous deep excavation projects for metro lines and transportation tunnels have been executed in soft clay in urban areas of coastal cities. Collapses of these deep excavations in soft clay are reported from time to time, including the infamous collapses of Nicoll highway excavation for metro circle line in Singapore (2004) and Xianghu excavation for a subway station in Hangzhou (2008). In routine practice, the stability or deformation of an excavation is calculated using the separated approaches, i.e., the limit equilibrium method and the finite element method (FEM), respectively. It is well recognized that the former usually does not consider the effect of excavation width, while the latter usually involves very sophisticated soil models and additional challenges posed by determination of model parameters. These limitations have led to the development of an upper bound method entitled mobilizable strength design (MSD) method by Prof. Bolton in Cambridge University, for predicting stability and deformation of excavations in soft clay in a unified yet simple manner. The authors (Wang & Long, 2014) have recently proposed an improved MSD method (i.e., MMSD method), where a more realistic plastic deformation mechanism is implemented for analyzing the stability of excavations in soft clay. The capability of MMSD for predicting deformation of excavations in soft clay is later verified against the field data of eight case histories (Wang et al., 2018). This study aims to examine the capability of MMSD to predict the collapse of Nicoll highway excavation and Xianghu excavation. It is shown that the MMSD method offers more accurately the prediction for the occurrence of the collapses of the two case histories than the existing limit equilibrium methods (standard method, Hsieh et al's. method and Su et al's. method) and finite element methods, as it accounts for a more realistic deformation mechanism for narrow deep excavations and the strength anisotropy of soft clay.
- MMSD method,
- soft clay,
- narrow excavation,
- collapse,
- deformation

FullText(HTML)

References (26)

References

[1]	张旷成, 李继民. 杭州地铁湘湖站“08.11.15”基坑坍塌事故分析[J]. 岩土工程学报, 2010, 32(增刊1): 338-342. https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC2010S1068.htm ZHANG Kuang-cheng, LI Ji-min. Accident analysis for “08.11.15” foundation pit collapse of Xianghu Station of Hangzhou metro[J]. Chinese Journal of Geotechnical Engineering, 2010, 32(S1): 338-341. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC2010S1068.htm
[2]	张雪婵. 软土地基狭长型深基坑性状分析[D]. 杭州: 浙江大学, 2012. ZHANG Xue-chan. Behavior of Narrow Deep Excavation in Soft Clay[D]. Hangzhou: Zhejiang University, 2012. (in Chinese)
[3]	李广信, 李学梅. 软黏土地基中基坑稳定分析中的强度指标[J]. 工程勘察, 2009(1): 1-4. https://www.cnki.com.cn/Article/CJFDTOTAL-GCKC201001003.htm LI Guang-xin, LI Xue-mei. The shear strength in stability analysis of subway pit in soft clay[J]. Geotechnical Investigation and Surveying, 2009(1): 1-4. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-GCKC201001003.htm
[4]	PUZRIN A M, ALONSO E E, PINYOL N M. Geomechanics of Failures, Chapter 6-Braced Excavation Collapse: Nicoll Highway, Singapore[M]. Dordrecht, the Netherlands: Springer, 2010.
[5]	WHITTLE A J, DAVIES R V. Nicoll highway collapse: evaluation of geotechnical factors affecting design of excavation support system[C]//International Conference on Deep Excavations, 2006, Singapore.
[6]	CORRAL G, WHITTLE A J. Re-analysis of deep excavation collapse using a generalized effective stress soil model[C]//Earth Retention Conference, 2010, Bellevue: 720-732.
[7]	肖晓春, 袁金荣, 朱雁飞. 新加坡地铁环线C824标段失事原因分析(二)——围护体系设计中的错误[J]. 现代隧道技术, 2009, 46(5): 66-72. https://www.cnki.com.cn/Article/CJFDTOTAL-XDSD200906005.htm XIAO Xiao-chun, YUAN Jin-rong, ZHU Yan-fei. Causation analysis of the collapse on Singapore MRT Circle Line Lot C824 (Part2): Critical Design Errors in Temporary Retaining System[J]. Modern Tunnelling Technology, 2009, 46(6): 29-34. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-XDSD200906005.htm
[8]	CHEN R P, LI Z C, CHEN Y M, et al. Failure investigation at a collapsed deep excavation in a very sensitive organic soft clay[J]. J Perform Constr Facil, 2015, 29(3): 04014078. doi: 10.1061/(ASCE)CF.1943-5509.0000557
[9]	张飞, 李镜培, 孙长安, 等. 软土狭长深基坑抗隆起破坏模式试验研究[J]. 岩土力学, 2016, 37(10): 2825-2832. https://www.cnki.com.cn/Article/CJFDTOTAL-YTLX201610012.htm ZHANG Fei, LI Jing-pei, SUN Chang-an, et al. Experimental study of basal heave failure mode of narrow-deep foundation pit in soft clay[J]. Rock and Soil Mechanics, 2016, 37(10): 2825-2832. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YTLX201610012.htm
[10]	GRIFFITHS DV, LANE PA. Slope stability analysis by finite elements[J]. Géotechnique, 1999, 49(3): 387-403. doi: 10.1680/geot.1999.49.3.387
[11]	曾国熙. φ_u=0分析法—一种对于饱和黏性土值得推广应用的方法[J]. 地基处理, 2001, 12(3): 3-18. ZENG Guo-xi. On the application of φ_u=0 analysis for saturated cohesive soils[J]. Ground Improvement, 2001, 12(3): 3-18. (in Chinese)
[12]	建筑地基基础设计规范：GB50007—2011[S]. 2011. Code for Design of Building Foundation: GB50007—2011[S]. 2011. (in Chinese)
[13]	WANG L Z, SHEN K L, YE S H. Undrained shear strength of K₀ consolidated soft soils[J]. Int J Geomech, 2008, 8(2): 105-113.
[14]	OSMAN A S, BOLTON M D. Ground movement predictions for braced excavations in undrained clay[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2006, 132(4): 1865-1876.
[15]	龙凡. 上限法分析深厚软土中基坑坑底抗隆起稳定性[D]. 杭州: 浙江大学, 2014. LONG Fan. Upper Bound Limit Analysis for Base Stability of Deep Excavation in Soft Clay[D]. Hangzhou: Zhejiang University, 2014. (in Chinese)
[16]	WANG L Z, LONG F. Base stability analysis of braced deep excavation in undrained anisotropic clay with upper bound theory[J]. Science China Technological Sciences, 2014, 57(9): 1865-1876.
[17]	WANG L Z, LIU Y J, HONG Y, et al. Predicting deformation of multipropped excavations in soft clay with amodified mobilizable strength design (MMSD) method[J]. Computers and Geotechnics, 2018, 104: 54-68.
[18]	COI Report of the Committee of Inquiry Into the Incident at the MRT Circle Line Worksite that Led Tocollapse of Nicoll Highway on 20 April 2004[R]. Singapore: Ministry of Manpower, 2005.
[19]	HSIEH P G, OU C Y, LIU H T. Basal heave analysis of excavations with consideration of anisotropic undrained strength of clay[J]. Can Geotech J, 2008, 45: 788-799.
[20]	SU S F, LIAO H J, LIN Y H. Base stability of deep excavation in anisotropic soft clay[J]. Journal of Geotechnical and Geoenvironmental Engineering, 1998, 124(9): 809-819.
[21]	LAM S Y, BOLTON M D. Energy conservation as a principle underlying mobilizable strength design for deep excavations[J]. Journal of Geotechnical and Geoenvironmental Engineering, ASCE, 2011, 137(11): 1062-1074.
[22]	王浩然, 王卫东, 黄茂松, 等. 基坑变形预测的改进MSD法[J]. 岩石力学与工程学报, 2011, 30(增刊1): 3245-3251. https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX2011S1085.htm WANG Hao-ran, WANG Wei-dong, HUANG Mao-song, et al. Modified mobilizable strength design (MSD) method on deformation predictions of foundation pit[J]. Chinese Journal of Rock Mechanics and Engineering, 2011, 30(S1): 3245-3251. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX2011S1085.htm
[23]	LAM S. Ground Movements Due to Excavation in Clay: Physical and Analytical Models[D]. Cambridge: University of Cambridge, 2010.
[24]	WANG Z W, NG C W W, LIU G B. Characteristics of wall deflections and ground surface settlements in Shanghai[J]. Can Geotech J, 2005, 42(5): 1243-1254.
[25]	ISHIHARA K, LEE W F. Forensic Diagnosis for Site Specific Ground Conditions in Deep Excavations of Subway Constructions[M]//COUTINHO R Q, MAYNE P W, eds. Geotechnical and Geophysical Site Characterization. Taylor & Francis, FL 2008, Boca Raton: 31-59.
[26]	BJERRUM L. Problems of soil mechanics and construction on soft clays and structurally unstable soils (collapsible expansive and others)[C]//Proceedings of 8th International Conference for Soil Mechanics and Foundation Engineering, 1973, Moscow: 111-159.

[1]	WU Yuan-hao, SUN Min, HONG Ze-qun. Laboratory tests on fluvial-thermal erosion of artificial frozen soil[J]. Chinese Journal of Geotechnical Engineering, 2022, 44(S2): 173-178. DOI: 10.11779/CJGE2022S2038
[2]	REN Lian-wei, XIAO Yang, KONG Gang-qiang, ZHANG Min-xia. Laboratory tests on soft ground improvement by chemical electro-osmosis method[J]. Chinese Journal of Geotechnical Engineering, 2018, 40(7): 1247-1256. DOI: 10.11779/CJGE201807011
[3]	SHANG Jin-rui, YANG Jun-jie, DONG Meng-rong, SONG Wen-feng. Laboratory tests on influences of skin degradation on bearing properties of piles[J]. Chinese Journal of Geotechnical Engineering, 2013, 35(zk2): 857-861.
[4]	CHEN Jian-sheng, HE Wen-zheng, WANG Shuang, HE Hai-qing. Laboratory tests on development of seepage failure of overlying layer during piping of two-stratum dike foundation[J]. Chinese Journal of Geotechnical Engineering, 2013, 35(10): 1777-1783.
[5]	LIANG Yue, CHEN Jian-sheng, CHEN Liang, SHEN Jian-qiang. Laboratory tests and analysis on piping in two-stratum dike foundation[J]. Chinese Journal of Geotechnical Engineering, 2011, 33(4): 624.
[6]	Development of a portable direct shear apparatus for both in-situ and laboratory tests[J]. Chinese Journal of Geotechnical Engineering, 2010, 32(6).
[7]	ZHANG Zhong-miao, ZOU Jian, HE Jing-yi, WANG Hua-qiang. Laboratory tests on compaction grouting and fracture grouting of clay[J]. Chinese Journal of Geotechnical Engineering, 2009, 31(12): 1818-1824.
[8]	CHEN Yumin, LIU Hanlong, SHAO Guojian, ZHAO Nan. Laboratory tests on flow characteristics of liquefied and post-liquefied sand[J]. Chinese Journal of Geotechnical Engineering, 2009, 31(9): 1408-1413.
[9]	ZHANG Yujun. Equivalent model and numerical analysis and laboratory test for jointed rockmasses[J]. Chinese Journal of Geotechnical Engineering, 2006, 28(1): 29-32.
[10]	Zhang Zhenying, Wu Shiming, Chen Yunmin. Experimental research on the parameter of life rubbish in city[J]. Chinese Journal of Geotechnical Engineering, 2000, 22(1): 38-42.