Abstract
Shield is used more and more widely, such as coal mine roadway, hydropower tunnel, traffic tunnel and so on. But Tunneling with a tunnel boring machine (TBM) may cause inevitable ground subsidence. Though over the world numerous researches have been conducted for surface settlement induced by TBM in soft ground, the researches of surface settlement induced by TBM in a sandy cobble stratum are limited and a comprehensive study of the mechanism of delayed settlement induced by TBM in a sandy cobble stratum is unavailable. A ground stable state or surface settlement can be determined based on real-time monitoring data for surface dynamic subsidence. Subsequently, TBM tunneling parameters can be adjusted to accommodate various geological conditions. A sand-pebble-soil matrix is a typical heterogeneous material. The macro-mechanical performance of this matrix significantly differs from any material. In a general situation with a low water level and minimal disturbance, a stratum can stabilize by itself for a long period of time. Considering the characteristics of the stratum, ground loss can be divided into two phases: immediate settlement, which tends to stabilize, and delayed settlement, which tends to occur in sand-cobble strata, where settlement develops at a much slower rate than in single-medium strata. Monitoring data is not sufficient to guide the construction in the case of delayed settlement. Cobble-soil matrix can be treated as a spatial structural system that is constituted by single granular soil, aggregates of granular soil and pebble grains. Based on Particle Flow Code in 2 Dimensions (PFC2D), the mechanical characteristics of the matrix and the TBM tunneling process were numerically simulated. Movements of the pebble grains were traced and recorded in real time. The model addressed the mechanism of surface collapse from the perspective of mesomechanics. According to the model, a matrix formed self-stabilizing arch that overlies an underground cavity seems gradually wear out with expanding the cavity and eventually penetrating to the ground surface. The law of ground movement and the formation mechanism of ground subsidence in TBM advancement were investigated. The main factors that affect surface subsidence are the speed of advancement, the underground water level and the supporting period. In the numerical analysis, the surface-loss lag was reproduced and the field monitoring data were verified. The findings of this study provide a new method for investigating ground subsidence in similar strata.
Similar content being viewed by others
References
Meng-shu W (2014) Tunneling by TBM/shield in China: state-of-art, problems and proposals. Tunnel Construction 34(3):179–187
Belle B, Foulstone A (2015) Explosion prevention in coal mine TBM drift—an operational safety knowledge share. Procedia Earth and Planetary Science 11:15–28
Zheng YL, Zhang QB, Zhao J (2016) Challenges and opportunities of using tunnel boring machines in mining. Tunnelling and Underground Space Technology 57:287–299
Brox D (2013) Technical considerations for TBM tunneling for mining projects. Transactions of the Society for Mining, Metallurgy and Exploration 334:498–505
Aston TRC, Gilby JL, Yuen CMK (1988) A comparison of rock mass disturbance in TBM and drill and blast drivages at the Donkin Mine, Nova Scotia. International Journal of Mining and Geological Engineering 6:147–162
Cigta M, Yagiz S, Ozdemir L (2001) Application of tunnel boring machines in underground mine development. IMCET, Turkey, pp 155–164
Zhao J (2007) Tunnelling in rocks-present technology and future challenges. In: World tunnel congress, pp 22–32
Cui K, Lin W (2016) Muck problem in subway shield tunneling in sandy cobble stratum. Polish Maritime Research 23:175–179
Song L (2011) Analysis of delayed settlement of soil pressure balance shield construction in water rich sandy gravel stratum and preventive measures. Journal of Changchun Institute of Technology (Natural Science Edition) 12(1):28–30
Donnelly LJ, Culshaw MG, Bell FG (2008) Long wall mining-induced fault reactivation and delayed subsidence ground movement in British coalfields. Quarterly Journal of Engineering Geology and Hydrogeology 41(3):301–314
Xu T, Yang T et al (2015) Mining induced strata movement and roof behavior in underground coal mine. Geomechanics and Geophysics for Geo-Energy and Geo-Resources 1:79–89
Chou W-I, Bobet A (2002) Predictions of ground deformations in shallow tunnels in clay. Tunnelling and Underground Space Technology 17:3–19
Leca E (2007) Settlements induced by tunneling in soft ground. Tunnelling and Underground Space Technology 22:119–149
Do N-A, Dias D et al (2014) Three-dimensional numerical simulation of a mechanized twin tunnels in soft ground. Tunnelling and Underground Space Technology 42:40–51
Dindarloo SR, Siami-Irdemoosa E (2015) Maximum surface settlement based classification of shallow tunnels in soft ground. Tunnelling and Underground Space Technology 49:320–327
Ercelebi SG, Copur H, Ocak I (2011) Surface settlement predictions for Istanbul Metro tunnels excavated by EPB-TBM. Environ Earth Sci 62:357–365
Loganathan N, Poulos HG (1998) Analytical prediction for tunneling induced ground movements in clays. Journal of Geotechnical and Geoenvironmental Engineering 124(9):846–856
Fang Y, Wang J et al (2014) Impact of shield tunneling on adjacent spread foundation on sandy cobble strata. J. Mod. Transport 22(4):244–255
Zhang ZX, Zhang H, Yan JY (2013) A case study on the behavior of shield tunneling in sandy cobble ground. Environ Earth Sci 69:1891–1900
He C, Feng K et al (2013) Surface settlement caused by twin-parallel shield tunnelling in sandy cobble strata. Journal of Zhejiang University Science A 13(11):858–869
Gao M, Zhao J, Li S, Qiu Z (2016) Theoretical model of the equivalent elastic modulus of a cobblestone–soil matrix for TBM tunneling. Tunnelling and Underground Space Technology 54:117–122
Li T, Huan Z (2012) Meso-macro analysis of surface settlement characteristics during shield tunneling in sandy cobble ground. Rock and Soil Mechanics 33(4):1141–1160
Feng H, Yang S (2014) Tunneling by EPB shield in gravel strata: case study on line 4 of Chengdu Metro. Tunnel Construction 34(3):274–279
Gao M, Zhang R, Wang M (2013) The Mechanism of Ground subsidence induced by EPB tunneling in sand and cobble stratum. In: International conference on geotechnical and earthquake engineering, pp 447–454
Jiang Y (2015) Study on delayed settlement formation induced by shield tunneling in sandy cobble strata. Chinese Journal of Underground Space and Engineering 11(1):171–177
Yazhou M (2012) Analysis and countermeasures of settlement for shield tunnelling in sand cobble stratum. Railway Construction Technology 4:65–68
Fang Y, He C et al (2017) Surface settlement prediction for EPB shield tunneling in sandy ground. KSCE Journal of Civil Engineering 989(8):1–11
Sharghi M, Chakeri H, Ozcelik Y (2017) Investigation into the effects of two component grout properties on surface settlements. Tunnelling and Underground Space Technology 63:205–216
Cundall PA, Strack ODL (1979) A discrete numerical model for granular assembly. Geotechnique 29:47–65
Itasca Consulting Group (2004) Particle flow code in 2 dimensions (PFC2D), version 3.1. User’s manual. Itasca Consulting Group, Minneapolis
Rowe RK, Lo KY, Kack GJ (1983) Method of estimating ground settlement above tunnels constructed in soft ground. Canadian Geotechnical Journal 20(1):11–22
Wang Q (2009) Research of the influence of Chengdu subway to the surrounding. Southwest Jiaotong University, Leshan
Wang M, Wei L, Lu J, Zhu Z (2001) Study of face stability of cobble-soil shield tunnelling at Chengdu metro. Rock and Soil Mechanics 32(1):99–105
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Gao, Mz., Zhang, Zl., Qiu, Zq. et al. The mechanism of hysteretic ground settlement caused by shield tunneling in mixed-face conditions. Geomech. Geophys. Geo-energ. Geo-resour. 4, 51–61 (2018). https://doi.org/10.1007/s40948-017-0074-2
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s40948-017-0074-2