Document Type : Original Research Paper


1 Faculty of Mining, Petroleum & Geophysics Eng., Shahrood University of Technology, Shahrood, Iran

2 Faculty of Mining Engineering, Isfahan University of Technology, Isfahan, Iran

3 Tehran Science and Research Branch Islamic Azad University., Iran


The stratified-sedimentary rock mass, as the typical host ground of coal mine tunnels, is characterized by highly non-isotropic deformation due to the very persistent discontinuity of bedding planes. This study evaluates the effect of tunnel location relative to the host ground strata on the excavation-induced displacements around a coal mine tunnel driven along the inclined coal seam. To achieve this goal, a calibrated finite element method (FEM) numerical model based on field monitoring displacements was developed for the coal mine tunnel at a depth of 300 m. This calibrated numerical model was then utilized to investigate the effect of the horizontal location of the tunnel on the induced displacement field through sensitivity analysis. Finally, the sensitivity analysis results were compared in terms of displacement components around the tunnel. The results of this study demonstrate a reasonable level of accuracy (for practical demands) of the calibrated numerical model, with an average error of about 8% for maximum displacements at measured points. The numerical models show an asymmetric spatial distribution of displacements around the tunnel due to the anisotropy of the rock mass, especially in the case of inclined layers. The arrangement of weak-strength coal and intercalary stone layers relative to the excavation line of the tunnel plays a key role in this issue. The critical state of displacements (maximum displacement in sensitivity analysis) occurs where the intersection line of the coal-intercalary stone is tangent to the tunnel excavation line. Additionally, the excavation-induced displacement decreases as the distance between the coal-intercalary stone interface and the tunnel increases, with a distance of about 1.5 m suggested for practical applications.


Main Subjects

[1]. Zhuo, X., Liu, X., Shi, X., Liang, L., & Xiong, J. (2022). The anisotropic mechanical characteristics of layered rocks under numerical simulation. Journal of Petroleum Exploration and Production Technology12(1), 51-62.
[2]. Zhang, Z. X., Xu, Y., Kulatilake, P. H. S. W., & Huang, X. (2012). Physical model test and numerical analysis on the behavior of stratified rock masses during underground excavation. International Journal of Rock Mechanics and Mining Sciences49, 134-147.
[3]. Hoek, E., Carranza-Torres, C., Diederichs, M. S., & Corkum, B. (2008, February). Integration of geotechnical and structural design in tunnelling. In Proceedings University of Minnesota 56th Annual Geotechnical Engineering Conference (Vol. 29, pp. 1-53). Minneapolis.
[4]. Fortsakis, P., Nikas, K., Marinos, V., & Marinos, P. (2012). Anisotropic behaviour of stratified rock masses in tunnelling. Engineering Geology141, 74-83.
[5]. Hoek, E., Marinos, P. G., & Marinos, V. P. (2005). Characterisation and engineering properties of tectonically undisturbed but lithologically varied sedimentary rock masses. International Journal of Rock Mechanics and Mining Sciences42(2), 277-285.
[6]. Cheng, L., Wang, H., Chang, X., Chen, Y., Xu, F., Zhang, B., & An, J. (2021). Experimental study on the anisotropy of layered rock mass under triaxial conditions. Advances in Civil Engineering2021, 1-13.
[7]. Tavallali, A., & Vervoort, A. (2010). Effect of layer orientation on the failure of layered sandstone under Brazilian test conditions. International journal of rock mechanics and mining sciences47(2), 313-322.
[8]. Tien, Y. M., Kuo, M. C., & Juang, C. H. (2006). An experimental investigation of the failure mechanism of simulated transversely isotropic rocks. International journal of rock mechanics and mining sciences43(8), 1163-1181.
[9]. Diederichs, M. S., & Kaiser, P. K. (1999). Stability of large excavations in laminated hard rock masses: the voussoir analogue revisited. International Journal of Rock Mechanics and Mining Sciences36(1), 97-117.
[10]. Evans, W. (1941). The strength of undermined strata. Transactions of the Institutions of Mining and Metallurgy50, 475-500.
[11]. Li, Y. (2019). Analytical examination for the stability of a competent stratum and implications for longwall coal mining. Energy Science & Engineering7(2), 469-477.
[12]. Shabanimashcool, M., & Li, C. C. (2015). Analytical approaches for studying the stability of laminated roof strata. International Journal of Rock Mechanics and Mining Sciences79, 99-108.
[13]. Sofianos, A. I. (1996, February). Analysis and design of an underground hard rock voussoir beam roof. In International journal of rock mechanics and mining sciences & geomechanics abstracts (Vol. 33, No. 2, pp. 153-166). Pergamon.
[14]. Yiouta-Mitra, P., & Sofianos, A. I. (2018). Μulti-jointed stratified hard rock roof analysis and design. International Journal of Rock Mechanics and Mining Sciences106, 96-108.
[15]. Cai, M., Morioka, H., Kaiser, P. K., Tasaka, Y., Kurose, H., Minami, M., & Maejima, T. (2007). Back-analysis of rock mass strength parameters using AE monitoring data. International Journal of Rock Mechanics and Mining Sciences44(4), 538-549.
[16]. Li, A., Liu, Y., Dai, F., Liu, K., & Wang, K. (2022). Deformation mechanisms of sidewall in layered rock strata dipping steeply against the inner space of large underground powerhouse cavern. Tunnelling and Underground Space Technology120, 104305.
[17]. Nehrii, S., Sakhno, S., Sakhno, I., & Nehrii, Т. (2018). Analyzing kinetics of deformation of boundary rocks of mine workings. Mining of mineral deposits, (12, Iss. 4), 115-123.
[18]. Chen, H. (1993). Failure Modes of Mine Tunnels in Stratified Rock Structures with Reference to Stress Field Conditions. Proceedings of 12th International Conference on Ground Control in Mining.
[19]. He, M. (2011). Physical modeling of an underground roadway excavation in geologically 45 inclined rock using infrared thermography. Engineering Geology121(3-4), 165-176.
[20]. He, M., Jia, X., Gong, W., & Faramarzi, L. (2010). Physical modeling of an underground roadway excavation in vertically stratified rock using infrared thermography. International Journal of Rock Mechanics and Mining Sciences47(7), 1212-1221.
[21]. Nehrii, S., Nehrii, T., Zolotarova, O., Aben, K., & Yussupov, K. (2021). Determination of the parameters of local reinforced zones under the protection means. In E3S Web of Conferences (Vol. 280, p. 08018). EDP Sciences.
[22]. Sun, X., Zhao, C., Zhang, Y., Chen, F., Zhang, S., & Zhang, K. (2021). Physical model test and numerical simulation on the failure mechanism of the roadway in layered soft rocks. International Journal of Mining Science and Technology31(2), 291-302.
[23]. Alejano, L. R., Taboada, J., García-Bastante, F., & Rodriguez, P. (2008). Multi-approach back-analysis of a roof bed collapse in a mining room excavated in stratified rock. International Journal of Rock Mechanics and Mining Sciences45(6), 899-913.
[24]. Cai, M. (2008). Influence of stress path on tunnel excavation response–Numerical tool selection and modeling strategy. Tunnelling and Underground Space Technology23(6), 618-628.
[25]. Do, N. A., Dias, D., Tran, T. T., Dao, V. D., & Nguyen, P. N. (2019). Behavior of noncircular tunnels excavated in stratified rock masses–Case of underground coal mines. Journal of Rock Mechanics and Geotechnical Engineering11(1), 99-110.
[26]. He, B., Zhang, Z., & Chen, Y. (2012). Unsymmetrical load effect of geologically inclined bedding strata on tunnels of passenger dedicated lines. Journal of Modern Transportation20, 24-30.
[27]. Zhang, Z. X., Xu, Y., Kulatilake, P. H. S. W., & Huang, X. (2012). Physical model test and numerical analysis on the behavior of stratified rock masses during underground excavation. International Journal of Rock Mechanics and Mining Sciences49, 134-147.
[28]. Tsesarsky, M., & Hatzor, Y. H. (2006). Tunnel roof deflection in blocky rock masses as a function of joint spacing and friction–a parametric study using discontinuous deformation analysis (DDA). Tunnelling and Underground Space Technology21(1), 29-45.
[29]. Winn, K., Wong, L. N. Y., & Alejano, L. R. (2019). Multi-approach stability analyses of large caverns excavated in low-angled bedded sedimentary rock masses in Singapore. Engineering Geology259, 105164.
[30]. Yang, X. X., Jing, H. W., & Qiao, W. G. (2018). Numerical investigation of the failure mechanism of transversely isotropic rocks with a particle flow modeling method. Processes6(9), 171.
[31]. Yaylaci, M. (2022). Simulate of edge and an internal crack problem and estimation of stress intensity factor through finite element method. Advances in nano research12(4), 405.
[32]. Yaylaci, M., ADIYAMAN, G., Oner, E., & Birinci, A. (2021). Investigation of continuous and discontinuous contact cases in the contact mechanics of graded materials using analytical method and FEM. Computers and Concrete27(3).
[33]. Zhang, X., Yang, J., & Chen, J. (2009). Stability Analysis of Tunnel Driven in Stratified Anisotropic Rockmass. In Recent Advancement in Soil Behavior, in Situ Test Methods, Pile Foundations, and Tunneling: Selected Papers from the 2009 GeoHunan International Conference (pp. 237-242).
[34]. RocScience Incorporated 2023, RocScience,
[35]. Małkowski, P. (2015). The impact of the physical model selection and rock mass stratification on the results of numerical calculations of the state of rock mass deformation around the roadways. Tunnelling and Underground Space Technology50, 365-375.
[36]. Martin, C. D., Kaiser, P. K., & McCreath, D. R. (1999). Hoek-Brown parameters for predicting the depth of brittle failure around tunnels. Canadian Geotechnical Journal36(1), 136-151.
[37]. Bieniawski, Z. T. (1978, October). Determining rock mass deformability: experience from case histories. In International journal of rock mechanics and mining sciences & geomechanics abstracts (Vol. 15, No. 5, pp. 237-247). Pergamon.
[38]. Dinc, O. S., Sonmez, H., Tunusluoglu, C., & Kasapoglu, K. E. (2011). A new general empirical approach for the prediction of rock mass strengths of soft to hard rock masses. International Journal of Rock Mechanics and Mining Sciences48(4), 650-665.
[39]. Hoek, E., & Diederichs, M. S. (2006). Empirical estimation of rock mass modulus. International journal of rock mechanics and mining sciences43(2), 203-215.
[40]. Barton, N. R. (1972, September). A model study of rock-joint deformation. In International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts (Vol. 9, No. 5, pp. 579-582). Pergamon.
[41]. Goodman, R. E. (1991). Introduction to rock mechanics. John Wiley & Sons.
[42]. Potts, D. M., Zdravković, L., Addenbrooke, T. I., Higgins, K. G., & Kovačević, N. (2001). Finite element analysis in geotechnical engineering: application (Vol. 2). London: Thomas Telford.
[43]. Hoek, E., Carranza-Torres, C., & Corkum, B. (2002). Hoek-Brown failure criterion-2002 edition. Proceedings of NARMS-Tac1(1), 267-273.
[44]. Barton, N., & Bandis, S. (1990). Review of predictive capabilities of JRC-JCS model in engineering practice. In Proceedings of the Rock Joints-Proceeding of a Regional Conference of the International Society for Rock Mechanics, Loen, pp. 603–610.