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J4  2012, Vol. 46 Issue (4): 665-671    DOI: 10.3785/j.issn.1008-973X.2012.04.014
    
Supporting pressure for earth pressure balance tunnel face stability
when  tunneling is implemented in saturated sandy soil
LIU Wei1, ZHANG Xiang-jie2, TANG Xiao-wu1, ZHU Ji3, CHEN Ren-peng1
1. MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering, Zhejiang University, Hangzhou 310058, China;
2. Civil Engineering Institute, Tokyo Institute of Technology, Tokyo 152-8552, Japan; 3. China Railway Siyuan Survey
and Design Group Limited Company, Wuhan 430000, China
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Abstract  

 Seepage application was considered in upper bound analysis to evaluate the seepage effect on face stability in order to avoid insufficient supporting pressure when earth pressure balance shield (EPB) is tunneling through aquifer sand stratum. Supporting pressure formula was proposed for EPB tunneling in saturated soil. Comparison and sensitivity analysis on coefficients of the supporting pressure equation indicated a slight effect of shield depth but obvious effect of shield diameter on face stability. Seepage factor takes larger portion in support pressure determination and becomes the most critical controlling factor with underground water level increasing. Stability equation deduced in the thesis gives out a straightforward criterion of support pressure determination. Case studies on the subway line show rational results from where important conclusions are obtained.



Published: 17 May 2012
CLC:  TU 434  
Cite this article:

LIU Wei, ZHANG Xiang-jie, TANG Xiao-wu, ZHU Ji, CHEN Ren-peng. Supporting pressure for earth pressure balance tunnel face stability
when  tunneling is implemented in saturated sandy soil. J4, 2012, 46(4): 665-671.

URL:

http://www.zjujournals.com/eng/10.3785/j.issn.1008-973X.2012.04.014     OR     http://www.zjujournals.com/eng/Y2012/V46/I4/665


饱和沙土中土压盾构开挖面极限支护力

为了避免土压平衡盾构在含水砂层中掘进时出现支护压力不足的现象,将渗流作用引入上限分析,以评估支护力对开挖面稳定的影响,得到土压平衡盾构在饱和沙土中掘进时的支护力方程.通过支护力方程各项系数比较以及敏感性分析,表明盾构直径与渗流作用对支护力影响显著.随着地下水位的升高,渗流因素在支护力中所占的比重提高;在高水头状况下,渗流作用大幅降低支护力,是造成开挖面前方土体失稳的最主要因素.给出较直观的支护力方程,采用简洁方法来分析在渗流作用下盾构支护力设置的安全性,结合地铁工程实例,分析开挖面失稳事故原因,给出合理的开挖面支护压力.

[1] 秦建设.盾构隧道施工中开挖面失稳事故分析[J].浙江建筑,2005,22(增刊): 48-54.
QIN Jianshe. The study on tunnel face instability in construction [J]. Zhejiang Construction, 2005, 22(supplement): 48-54.

[2] 竺维彬.鞠世健.地铁盾构施工风险源及典型事故的研究[M].广州:暨南大学出版社,2009: 71-82.
[3] 黄正荣,朱伟,梁精华,等.盾构法隧道开挖面极限支护压力研究[J].土木工程学报,2006,39(10): 112-116.
HUANG Zhengrong, ZHU Wei, LIANG Jinghua, et al. A study on the limit support pressure at excavation face of shield tunneling [J]. China Civil Engineering Journal, 2006, 39(10): 112-116.
[4] BROMS B B, BENNERMARK H. Stability of clay at vertical openings [J]. Journal of Soil Mechanics and Foundations Division, ASCE, 1967, 93(1): 71-94.
[5] LECA E, DORMIEUX L. Upper and lower bound solutions for the face stability of shallow circular tunnels in frictional material [J]. Geotechnique, 1990, 40(4): 581-606.
[6] ANAGNOSTOU G, KOVARI K. Face stability of slurryshielddriven tunnels [J]. Tunneling and Underground Space Technology, 1994, 9(2): 165-174.
[7] ANAGNOSTOU G, KOVARI K. Face stability conditions with earthpressurebalanced shield [J]. Tunneling and Underground Space Technology, 1996, 11(2): 165-173.
[8] LEE I M, NAM S W. The study of seepage forces acting on the tunnel lining and tunnel face in shallow tunnels [J]. Tunneling and Underground Space Technology, 2001, 16(1): 31-40.
[9] 高健,张义同,乔金丽.渗流力对隧道开挖面稳定性影响分析[J].岩土工程学报,2009,31(10): 1548-1553.
GAO Jian, ZHANG Yitong, QIAO Jinli. Face stability analysis of tunnels with consideration of seepage forces [J]. Chinese Journal of Geotechnical Engineering, 2009, 31(10): 1548-1553.
[10] 许巧详,刘斌,金明.地铁隧道穿越江河地质稳定性及渗流特性数值分析[J].中国安全生产科学技术,2007,3(1): 62-65.
XU Qiaoxiang, LIU Bin, JIN Ming. Simulation of the geological stability and the osmotic characteristics as subway tunnel crossing river [J]. Journal of Safety Science and Technology, 2007, 3(1): 62-65.
[11] 于宁,朱合华.盾构施工仿真及其相邻影响的数值分析[J].岩土力学,2004,25(2): 292-296.
YU Ning, ZHU Hehua. The simulation of shield Tunnel construction and the analysis of its influence upon surrounding environments [J]. Rock and Soil Mechanics, 2004, 25 (2): 292-296.
[12] 周小文,濮家骝.砂土中隧洞开挖稳定机理及松动土压力研究[J].长江科学院院报,1999,16(4): 9-14.
ZHOU Xiaowen, PU Jialiu. Study on stability mechanism and relaxed soil pressure in sandy soil during excavation [J]. Journal of Yangtze River Scientific Research Institute, 1999, 16(4): 9-14.
[13] CHAMBON P, CORTE J F. Shallow tunnels in cohesionless soil: stability of tunnel face [J]. Journal of Geotechnical Engineering, 1994, 120(7): 1148-1165.

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