Three-dimensional stochastic geological modeling for probabilistic stability analysis of a circular tunnel face

AbstractTunnel stress path during excavation was investigated in the study scope. The triple-center section is commonly designated for highway tunnels, but the analytical solution of the stress state for a non-circular tunnel section with multiple bench excavations is difficult to obtain. Our investigation provides an algorithmic procedure which reliably evaluates stress adjustment of a bench excavation with respect to the three-dimensional state of stress. Evaluation of a safety factor at the tunnel face during advancement is performed following the stress path and principal stress space.

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Three-dimensional stability analysis of a longitudinally inclined shallow tunnel face

Computers and Geotechnics ◽

10.1016/j.compgeo.2017.01.015 ◽

2017 ◽

Vol 87 ◽

pp. 32-48 ◽

Cited By ~ 13

Author(s):

LianHeng Zhao ◽

DeJian Li ◽

Liang Li ◽

Feng Yang ◽

Xiao Cheng ◽

...

Keyword(s):

Stability Analysis ◽

Dimensional Stability ◽

Three Dimensional ◽

Shallow Tunnel ◽

Tunnel Face

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Discontinuous mechanical analysis of manifold element strain of rock slope based on open source Gempy

E3S Web of Conferences ◽

10.1051/e3sconf/202124803084 ◽

2021 ◽

Vol 248 ◽

pp. 03084

Author(s):

Jie Wu ◽

Bingyang Sun

Keyword(s):

Rock Mass ◽

Stability Analysis ◽

Open Source ◽

Interpolation Method ◽

Data Use ◽

Three Dimensional ◽

Geological Model ◽

Geological Modeling ◽

Fault Surface ◽

Interactive Operation

Three-dimensional geological modeling is an important means to transparently study the three-dimensional geological spatial structure and change trend of major complex rock mass projects, and plays a very important role in the decision-making and mining of major projects. Today’s modeling methods rely too much on the required data, the process is cumbersome and the time is relatively long. Therefore, based on the above discussion, this article uses a complete open source code geological modeling method here, based on the implicit potential field interpolation method of the open source GemPy package, using this interpolation algorithm can be relatively simple to build a complex full three-dimensional geological model, Including fault network, fault surface interaction, unconformity and dome structure. The article describes in detail how to construct the faults and strata of the 3D geological model, and how to add topographic maps, and use the generated model as input data, use MOOSE to voxelize it, and export the required data, use NMM Perform stability analysis. This method has the advantages of simple operation, fast modeling speed, and visual interactive operation. The establishment of a three-dimensional geological model of the fractured rock mass was very effective, laying a solid foundation for the subsequent stability analysis.

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Effect of Longitudinal Gradient on 3D Face Stability of Circular Tunnel in Undrained Clay

Advances in Civil Engineering ◽

10.1155/2020/5846151 ◽

2020 ◽

Vol 2020 ◽

pp. 1-12

Author(s):

Zhengxing Wang ◽

Yuke Wang ◽

Shumao Wang ◽

Bin Li ◽

Hu Wang

Keyword(s):

Upper Bound ◽

Three Dimensional ◽

Optimization Procedure ◽

Upward Movement ◽

Circular Tunnel ◽

Longitudinal Gradient ◽

Tunnel Face ◽

Face Stability ◽

Collapse Pressure ◽

Limit Pressure

The longitudinal gradient existed in shield-driven tunnel crossing river or channel has a longitudinal gradient, which is often ignored in most stability analyses of the tunnel face. Considering the influence of the longitudinal gradient into A(a) continuous velocity field, the present paper, conducting a limit analysis of the tunnel face in undrained clay, adopted to yield the upper-bound solutions of the limit pressure supporting on a three-dimensional tunnel face. The least upper bounds of the collapse and blow-out pressures can be obtained by conducting an optimization procedure. These upper-bound solutions are given in the design charts, which provide a simple way to assess the range of the limit pressure in practice. The influence of the longitudinal gradient becomes more significant with the increase of γD/su and C/D. The blow-out pressure for tunneling in a downward movement could be overestimated and the collapse pressure for tunneling in an upward movement could be conversely underestimated, with ignoring the influence of the longitudinal gradient.

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Three-Dimensional Static and Seismic Stability Analysis of a Tunnel Face Driven in Weak Rock Masses

International Journal of Geomechanics ◽

10.1061/(asce)gm.1943-5622.0001174 ◽

2018 ◽

Vol 18 (6) ◽

pp. 04018055 ◽

Cited By ~ 8

Author(s):

Qiujing Pan ◽

Daniel Dias

Keyword(s):

Stability Analysis ◽

Three Dimensional ◽

Seismic Stability ◽

Weak Rock ◽

Rock Masses ◽

Tunnel Face ◽

Weak Rock Masses

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Three-dimensional numerical stability analysis of the Oyu Tolgoi open pit

Proceedings of the 2013 International Symposium on Slope Stability in Open Pit Mining and Civil Engineering ◽

10.36487/acg_rep/1308_44_smithyman ◽

2013 ◽

Author(s):

Megan Smithyman ◽

Humberto Puebla ◽

Al Chance ◽

Richard Beddoes ◽

Ashley Creighton

Keyword(s):

Stability Analysis ◽

Numerical Stability ◽

Three Dimensional ◽

Open Pit ◽

Numerical Stability Analysis

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Stability Analysis of the Nanjung Water Diversion Twin Tunnels based on Convergence Measurement

Indonesian Mining Professionals Journal ◽

10.36986/impj.v1i1.11 ◽

2019 ◽

Vol 1 (1) ◽

pp. 49-60

Author(s):

Simon Heru Prassetyo ◽

Ganda Marihot Simangunsong ◽

Ridho Kresna Wattimena ◽

Made Astawa Rai ◽

Irwandy Arif ◽

...

Keyword(s):

Stability Analysis ◽

Convergence Rate ◽

Critical Strain ◽

Convergence Rates ◽

Strain Analysis ◽

Water Diversion ◽

Tunnel Face ◽

Tunnel Stability ◽

The Stability ◽

Twin Tunnels

This paper focuses on the stability analysis of the Nanjung Water Diversion Twin Tunnels using convergence measurement. The Nanjung Tunnel is horseshoe-shaped in cross-section, 10.2 m x 9.2 m in dimension, and 230 m in length. The location of the tunnel is in Curug Jompong, Margaasih Subdistrict, Bandung. Convergence monitoring was done for 144 days between February 18 and July 11, 2019. The results of the convergence measurement were recorded and plotted into the curves of convergence vs. day and convergence vs. distance from tunnel face. From these plots, the continuity of the convergence and the convergence rate in the tunnel roof and wall were then analyzed. The convergence rates from each tunnel were also compared to empirical values to determine the level of tunnel stability. In general, the trend of convergence rate shows that the Nanjung Tunnel is stable without any indication of instability. Although there was a spike in the convergence rate at several STA in the measured span, that spike was not replicated by the convergence rate in the other measured spans and it was not continuous. The stability of the Nanjung Tunnel is also confirmed from the critical strain analysis, in which most of the STA measured have strain magnitudes located below the critical strain line and are less than 1%.

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