logo

SCIENCE CHINA Technological Sciences, Volume 61 , Issue 5 : 735-747(2018) https://doi.org/10.1007/s11431-017-9151-2

Seismic stability of loess tunnels under the effects of rain seepage and a train load

More info
  • ReceivedApr 6, 2017
  • AcceptedSep 20, 2017
  • PublishedJan 11, 2018

Abstract

Loess tunnels are widely used in transportation engineering and are irreplaceable parts of transportation infrastructure. In this paper, a dynamic finite element method is used to analyze the coupled effects of a train vibration load and rainfall seepage. By calculating the variation in the safety factor of a loess tunnel because of the effects of various factors, such as different rainfall intensities and soil thicknesses, the dynamic stability of the loess tunnel is studied under the condition of a near-field pulse-like earthquake. The results show that the security and stability of the tunnel decrease gradually with decreasing burial depth. In addition, the plastic strain of the tunnel is mainly distributed on both sides of the vault and the feet, and the maximum value of the critical strain occurs on both sides of the arch feet. Because of the effects of the train vibration load and rainfall seepage, the safety factor of the loess tunnel structure decreases to a certain degree. Moreover, the range and maximum value of the plastic strain increase to various degrees.


Funded by

the National Natural Science Foundation of China(Grant,No.,51478212)

the Education Ministry Doctoral Tutor Foundation of China(Grant,No.,20136201110003)


Acknowledgment

This work was supported in part by the National Natural Science Foundation of China (Grant No. 51478212) and the Education Ministry Doctoral Tutor Foundation of China (Grant No. 20136201110003).


References

[1] Xian D Q. Analysis of main causes of foundation engineering accidents (in Chinese). Mineral Explor, 2004, 7: 11–13. Google Scholar

[2] Pan C S, Pande G N. Analysis of dynamic load response of loess tunnel by finite element method (in Chinese). China Civil Eng J, 1984: 21–30. Google Scholar

[3] Xie W P, Wang G B, Yu Y L. Calculation of soil deformation caused by moving load (in Chinese). Chin J Geotech Eng, 2004, 2: 318–322. Google Scholar

[4] Bian X C. Dynamic response analysis of foundation and tunnel under moving load of high speed train (in Chinese). Dissertation of Doctoral Degree. Zhejiang: Zhejiang University, 2005. Google Scholar

[5] Li L, Zhang B Q, Yang X L. Dynamic response analysis of large section tunnel under vibration load of high speed train (in Chinese). Chin J Rock Mech Eng, 2005, 24: 4259–4265. Google Scholar

[6] Zhai L H, Shi H O, Jiang P P. Analysis of soil dynamic response and impact of high speed railway vibration load on metro tunnel (in Chinese). Urban Mass Transit, 2012, 15: 32–37. Google Scholar

[7] Ye F, Ding W Q, Wang G B, et.al. Study on the influence of train moving load on stability of down road tunnel (in Chinese). Rock Soil Mech, 2008, 29: 549–552. Google Scholar

[8] Zhang K. Vibration response and settlement of loess stratum under subway driving load (in Chinese). Dissertation of Doctoral Degree. Xi’an: Xi’an University of Architecture and Technology, 2011. Google Scholar

[9] Wang X, Han X, Zhou H L. Study of the numerical calculation of ground response under metro traffic loading in a loess area. Mod Tunneling Technol, 2014, 51: 152–160. Google Scholar

[10] Zheng J, Yu S F. Dynamic responses of underground structures generated by high-speed train loads (in Chinese). Struct Eng, 2013, 29: 46–50. Google Scholar

[11] Farhadian H, Aalianvari A, Katibeh H. Optimization of analytical equations of groundwater seepage into tunnels: A case study of Amirkabir tunnel. J Geol Soc India, 2012, 80: 96-100 CrossRef Google Scholar

[12] Liu J S. Seepage formula of a fracture subject to normal stress (in Chinese). Hydrol Eng Geol, 1987: 36–37. Google Scholar

[13] Anagnostou G, Kovári K. Face stability conditions with earth-pressure-balanced shields. Tunn Undergr Space Tech, 1996, 11: 165-173 CrossRef Google Scholar

[14] Broere W. Face stability calculation for a slurry shield in heterogeneous soft soils. In: Negro Jr A, Ferreira A A, Eds. Tunnels and Metropolises. Netherlands: A.A. Balkema Publishers, 1998. 215–227. Google Scholar

[15] Li X, Zhang W, Li D, et al. Influence of underground water seepage flow on surrounding rock deformation of multi-arch tunnel. J Cent South Univ Technol, 2008, 15: 69-74 CrossRef Google Scholar

[16] Zhang W J, Chen Y M, Ling D S. Seepage and stability analysis of bank slopes (in Chinese). J Hydraul Eng, 2005, 36: 1510–1516. Google Scholar

[17] Lee I M, Nam S W, Ahn J H. Effect of seepage forces on tunnel face stability. Can Geotech J, 2003, 40: 342-350 CrossRef Google Scholar

[18] Li Z L, Ren Q W, Wang Y H. Elasto-plastic analytical solution of deep-buried circle tunnel considering fluid flow field (in Chinese). Chin J Rock Mech Eng, 2004, 23: 1291–1295. Google Scholar

[19] Ji X M, Wang Y H. Hydraulic coupling analysis of tunnel excavation process (in Chinese). Chin J Undergr Space Eng, 2005, 1: 848–852. Google Scholar

[20] Ji X M. Discussion on the research of coupled solid and fluid flow in tunnel engineering (in Chinese). Chin J Undergr Space Eng, 2006, 2: 149–154. Google Scholar

[21] Lee I M, Nam S W. The study of seepage forces acting on the tunnel lining and tunnel face in shallow tunnels. Tunn Undergr Space Tech, 2001, 16: 31-40 CrossRef Google Scholar

[22] Lee I M, Nam S W. Effect of tunnel advance rate on seepage forces acting on the underwater tunnel face. Tunn Undergr Space Tech, 2004, 19: 273-281 CrossRef Google Scholar

[23] Li D Y, Li X B, Zhang W, et al. Stability analysis of surrounding rock of multi arch tunnel based on fluid structure interaction theory (in Chinese). Chin J Rock Mech Eng, 2007, 26: 1056–1064. Google Scholar

[24] Li Z P, Zhang M. Study on transient safety factor of unsaturated soil slope considering rainfall infiltration (in Chinese). China Civil Eng J, 2001, 34: 57–60. Google Scholar

[25] Cheng X, Dowding C H, Tian R. New methods of safety evaluation for rock/soil mass surrounding tunnel under earthquake. J Cent South Univ, 2014, 21: 2935-2943 CrossRef Google Scholar

[26] Liu M, Huang M S, Li J J. Long term settlement analysis of saturated soft clay under subway load (in Chinese). Chin J Undergr Space Eng, 2006, 2: 813–817. Google Scholar

[27] Cheng X, Feng H, Qi S, et al. Dynamic response of curved wall LTSLS under the interaction of rainwater seepage and earthquake. Geotech Geol Eng, 2017, 35: 903-914 CrossRef Google Scholar

[28] Zheng Y R, Zhao S Y. Application of strength reduction FEM in soil and rock slope (in Chinese). Chin J Rock Mech Eng, 2004, 23: 3381–3388. Google Scholar

[29] Cheng X S, Zheng Y R, Tian R R. Dynamic finite element strength reduction method of earthquake stability analysis of surrounding rock of tunnel (in Chinese). Rock Soil Mech, 2011, 32: 1241–1248. Google Scholar

[30] Cheng X S, Zheng Y R. Calculation discussion about safety factor of unlined loess tunnel wall rock structure under earthquake (in Chinese). Rock Soil Mech, 2011, 32: 761–766. Google Scholar

[31] Xie W P, Sun H G. FEM analysis on wave propagation in soils induced by high speed train loads (in Chinese). Chin J Rock Mech Eng, 2003, 22: 1180–1184. Google Scholar

[32] Chen Z Y, Zhou J X, Wang H J. Soil Mechanics. Beijing: Tsinghua University Press, 2002. Google Scholar

[33] Wang T H, Luo Y, Zhang H. Two-dimensional steady flow rate equation for loess joints (in Chinese). Chin J Geotech Eng, 2013, 35: 1115–1120. Google Scholar

[34] Li P C, Kong X Y, Lu D T. Mathematical modeling of flow in saturated porous media on account of fluid-structure coupling effect (in Chinese). J Hydrodyn, 2003, 18: 419–426. Google Scholar

[35] Yuan L J, Li Z S, Wu S Z, et al. Engineering Seepage Mechanics and Its Application. Beijing: China Building Materials Press, 2001. Google Scholar

[36] ADINA R & D, Inc. ADINA Theory and Modeling Guide, Volume I: ADINA Solids & Structures. Watertown MA, 2010. 559–561. Google Scholar

[37] Wang X, Wang L B. Dynamic analysis of a water-soil-pore water coupling system. Comp Struct, 2007, 85: 1020-1031 CrossRef Google Scholar

[38] Hu Z Y, Luo Y S, Li Y. Experimental study on damping ratio variation characteristics of loess in different areas (in Chinese). Earthq Eng Eng Vib, 2010, 30: 167–172. Google Scholar

[39] Chen L, Chen G X, Li L M. Seismic response characteristics of the double-layer vertical overlapping metro tunnels under near-field and far-field ground motions (in Chinese). China Railw Sci, 2010, 31: 79–86. Google Scholar

[40] Cui Y X, Bi Z Q, Gong Q M. Dynamic analysis of ballastless track-subgrade considering frequency-dependent subgrade equivalent parameters (in Chinese). China Sciencepaper, 2015, 10: 745–749. Google Scholar

[41] Su H J, Liu Z Z, Huang Z H, et al. A model test investigation on infiltration depth of soil slope under sustained rainfall (in Chinese). China Sci Paper, 2015, 10: 91–94. Google Scholar

  • Figure 1

    Mohr-Coulomb failure curve under dynamic loading.

  • Figure 2

    Acceleration time-history curve of 8 degree rare earthquake (near-field earthquake with pulses).

  • Figure 3

    Train load time-history curve.

  • Figure 4

    (Color online) Analysis model.

  • Figure 5

    Horizontal displacement time-history curves at node 818. (a)–(c) The overlying loess thicknesses are 30, 60 and 80 m, respectively.

  • Figure 6

    (Color online) Plastic strain nephogram of the loess mass of the tunnel for overlying loess thicknesses of 30 (a), 60 (b) and 80 m (c). The safety factors of the tunnels are 2.253 (a), 2.273 (b) and 2.654 (c).

  • Figure 7

    Horizontal displacement time-history curves of the right apex of the tunnel. (a)–(c) The overlying loess thicknesses are 30, 60 and 80 m, respectively.

  • Figure 8

    (Color online) Plastic strain nephogram of the loess mass for overlying loess thicknesses of 30 (a), 60 (b) and 80 m (c). The safety factors of the tunnels are 2.250 (a), 2.265 (b), and 2.647 (c) respectively.

  • Figure 9

    Horizontal displacement time-history curves at node 818. (a)–(c) The overlying loess thicknesses are 30, 60 and 80 m, respectively.

  • Figure 10

    (Color online) Plastic strain nephogram of the loess mass of a tunnel for overlying loess thicknesses of 30 (a), 60 (b) and 80 m (c). The safety factors of the tunnels are 2.248 (a), 2.260 (b) and 2.641 (c).

  • Figure 11

    Safety factor of the loess tunnel for a train load and different rainfall intensities.

  • Table 1   Concrete parameters

    Material type

    Elastic modulus (GPa)

    Poisson’s ratio

    Unit weight (kN/m3)

    Cohesion (MPa)

    Initial lining

    30

    0.2

    25

    Secondary lining

    30

    0.2

    25

  • Table 2   Loess parameters

    Type

    Elastic modulus (MPa)

    Poisson’s ratio

    Unit weight (kN/m3)

    Cohesion (MPa)

    Internal friction angle (°)

    Before the rain

    85

    0.35

    18.5

    0.1

    25

    After the rain

    30

    0.35

    15.58

    0.075

    19.8

  • Table 3   The material parameters of track bed

    Material types

    Elastic modulus (MPa)

    Poisson′s ratio

    Unit weight (kN/m3)

    Filling material at the bottom of the tunnel

    17.5

    0.2

    18

    Concrete foundation

    30

    0.2

    25

    Track slab

    30

    0.2

    25

Copyright 2020 Science China Press Co., Ltd. 《中国科学》杂志社有限责任公司 版权所有

京ICP备17057255号       京公网安备11010102003388号