Numerical Analysis of Stress Distribution During Tunneling in Clay Stone Rock

Document Type: Original Article

Authors

Department of Civil Engineering, University of Diyala, Diyala, Iraq

Abstract

Modern technology has been used to build tunnels in recent years by means of drilling machines (TBM) that were used for civil engineering work in large cities to reduce the harmful effects of spending on the surface of the earth significantly. To build the tunnel, numerical modeling was used on the basis of the finite element method to predict stress behavior during the tunnel construction process. Tunnel simulation model by using the numerical method (FEM) with the Hoek-Brown model, which includes calculating the behavior of predicting stress-that surrounds the tunnel and analysis during the process of building the tunnel and compared with the natural state of the rocks during the different tunnel construction stages. Vertical stresses at the top and bottom of the tunnel are reduced during the advance of tunneling while horizontal stresses are increased. TBM progression is reflected in phases through one to five by performing an axial symmetric FE analysis, math calculation results revealed significant stress changes occurring in rock regions near the boundary of the tunnel. In other words, proximity to rocks is mostly affected by the tunnel. These pressure variations decrease as you move away from the tunnel horizontally and the seams reach extremely small values for distances greater than (2D) meters from the edge of the tunnel, where D is the diameter of tunnel.

Keywords


1.     Maynar, M.J. and Rodríguez, L.E., "Discrete numerical model for analysis of earth pressure balance tunnel excavation", Journal of Geotechnical and Geoenvironmental Engineering,  Vol. 131, No. 10, (2005), 1234-1242. https://doi.org/10.1061/(ASCE)1090-0241(2005)131:10(1234)

2.     Shaalan, H.H., Azit, R. and Ismail, M.A.M., "Numerical analysis of tbm tunnel lining behavior using shotcrete constitutive model", Civil Engineering Journal,  Vol. 4, No. 5, (2018), 1046-1065. Doi.org/10.28991/cej-0309155

3.     Zhang, N., Wang, W., Yang, Z. and Zhang, J., "Numerical simulation on the stability of surrounding rock of horizontal rock strata in the tunnel", Civil Engineering Journal,  Vol. 3, No. 12, (2017). Doi.org/10.28991/cej-030948

4.     Beer, G., "Numerical simulation in tunnelling, Springer Science & Business Media,  (2003). https://doi.org/10.1007/978-3-7091-6099-2

5.     Jing, L. and Hudson, J., "Numerical methods in rock mechanics", International Journal of Rock Mechanics and Mining Sciences,  Vol. 39, No. 4, (2002), 409-427. https://doi.org/10.1016/S1365-1609(02)00065-5

6.     Harrison, J.P., Hudson, J.A. and Popescu, M., "Engineering rock mechanics: Part 2. Illustrative worked examples", Appl. Mech. Rev.,  Vol. 55, No. 2, (2002), B30-B31. https://doi.org/10.1115/1.1451165

7.     Jing, L., "A review of techniques, advances and outstanding issues in numerical modelling for rock mechanics and rock engineering", International Journal of Rock Mechanics and Mining Sciences,  Vol. 40, No. 3, (2003), 283-353. https://doi.org/10.1016/S1365-1609(03)00013-3

8.     Akram, M.S., Ahmed, L., Ullah, M.F., Rehman, F. and Ali, M., "Numerical verification of empirically designed support for a headrace tunnel", Civil Engineering Journal,  Vol. 4, No. 11, (2018), 2575-2587. Doi.org/10.28991/cej-0391182

9.     Forcellini, D., Tanganelli, M. and Viti, S., "Response site analyses of 3d homogeneous soil models", Emerging Science Journal,  Vol. 2, No. 5, (2018), 238-250. Doi.org/10.28991/esj-2018-01148

10.   Andriani, G.F. and Parise, M., "Applying rock mass classifications to carbonate rocks for engineering purposes with a new approach using the rock engineering system", Journal of Rock Mechanics and Geotechnical Engineering,  Vol. 9, No. 2, (2017), 364-369. https://doi.org/10.1016/j.jrmge.2016.12.001

11.   Vakili, A., "An improved unified constitutive model for rock material and guidelines for its application in numerical modelling", Computers and Geotechnics,  Vol. 80, No., (2016), 261-282. https://doi.org/10.1016/j.compgeo.2016.08.020

12.   Bobet, A., "Numerical methods in geomechanics", The Arabian Journal for Science and Engineering,  Vol. 35, No. 1B, (2010), 27-48.

13.   Rasouli, M., "Engineering geological studies of the diversion tunnel, focusing on stabilization analysis and support design, iran", Engineering Geology,  Vol. 108, No. 3-4, (2009), 208-224. https://doi.org/10.1016/j.enggeo.2009.07.007

14.   Abel, J.F. and Lee, F.T., "Stress changes ahead of an advancing tunnel", in International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, Elsevier. Vol. 10, No. 6, (1973), 673-697. https://doi.org/10.1016/0148-9062(73)90013-2

15.   Martin, C.D., "Seventeenth canadian geotechnical colloquium: The effect of cohesion loss and stress path on brittle rock strength", Canadian Geotechnical Journal,  Vol. 34, No. 5, (1997), 698-725. https://doi.org/10.1139/t97-030

16.   Hoek, E. and Brown, E., "Underground excavations in rock. Inst. Of mining and metallurgy", Stephan Austin And Sons London, 527s,  (1980). http://worldcat.org/isbn/0900488557

17.   Brinkgreve, R. and Vermeer, P., "Plaxis 3d-finite element code for soil and rocks analysis", Balkema, Rotterdam, The Netherlands,  (2012).