在隧道数值模拟中,模型尺寸即代表隧道围岩工程边界范围,对隧道稳定性分析及设计具有重要意义。基于Mohr-Coulomb准则,以围岩应力扰动幅度为定量指标,提出了考虑围岩质量的隧道围岩工程边界估算方法。利用了4个不同质量等级隧道围岩案例进行验证对比。结果表明,估算方法可快速针对不同级别围岩的工程边界范围进行预估,其中Ⅲ和Ⅳ级围岩的估算结果与数值模拟结果非常接近。进一步分析侧压力系数和洞室几何形状对隧道围岩工程边界位置的影响。结果显示,侧压力系数的影响非常明显,而洞室几何形状的影响微乎其微。该方法可为保证地下隧道工程数值建模分析的准确度提供思路。
In numerical modelling of tunnelling, the size of the numerical model, representing the range of engineering boundary for tunnel surrounding rock, is of great significance for tunnel stability analysis and design. Based on Mohr-Coulomb criterion, an estimation method was proposed for the engineering boundary range of tunnel surrounding rock considering rock mass quality, taking rock stress disturbance amplitude as a quantitative indicator. Rock masse of four quality levels were utilized to validate the estimation method. The results show that: The estimation method can be used to quickly predict the engineering boundary range for rock masses of different qualities, in which the estimation results for rock mass grade Ⅲ and Ⅳ are highly closed to the numerical results. Furthermore, the impacts of lateral pressure coefficient and excavation shape on the engineering boundary range were investigated. The results indicate the lateral pressure coefficient has an obvious effect while the excavation shape has a negligible one. This proposed estimation method provides advice for the accuracy of the numerical modelling design and analysis in underground tunnels.
[1] 严克强.不对称荷载作用下圆洞围岩塑性区的估算方法[J]. 岩土工程学报,1980(2):74-79.(Yan Keqiang. Estimation method of plastic zone for circular tunnel rock under asymmetric loads[J]. Chinese Journal of Geotechnical Engineering, 1980(2): 74-79. (in Chinese))
[2] 谢家冲,黄昕,金国龙,等.局部水力交互下盾构隧道渗流与力学响应研究[J]. 岩土力学,2023,44(4):1179-1189. (Xie Jiachong, Huang Xin, Jin Guolong, et al. Seepage characteristics and mechanical response of shield tunnels under localized leakage and exosmosis[J]. Rock and Soil Mechanics, 2023, 44(4):1179-1189. (in Chinese))
[3] Jaeger J C. Friction of rocks and stability of rock slopes[J]. Geotechnique, 1971, 21(2): 97-134.
[4] Hoek E, Carranza-Torres C, Corkum B. Hoek-Brown failure criterion-2002 edition[J]. Proceedings of NARMS-Tac, 2002, 1(1): 267-273.
[5] Hoek E, Brown E T. The hoek-brown failure criterion and GSI-2018 edition[J]. Journal of Rock Mechanics and Geotechnical Engineering, 2019, 11(3): 445-463.
[6] 孙训方, 方孝淑, 关来泰. 材料力学[M]. 北京: 高等教育出版社, 2013. (Sun Xunfang, Fang Xiaoshu, Guan Laitai. Material mechanics[M]. Beijing: Higher Education Press, 2013. (in Chinese))
[7] Chen X, Guo H, Zhao P, et al. Numerical modeling of large deformation and nonlinear frictional contact of excavation boundary of deep soft rock tunnel[J]. Journal of Rock Mechanics and Geotechnical Engineering, 2011, 3: 421-428.
[8] Zhao C, Alimardani Lavasan A, Schanz T. Application of submodeling technique in numerical modeling of mechanized tunnel excavation[J]. International Journal of Civil Engineering, 2019, 17: 75-89.
[9] 刘少峰,刘云,苏永华.基于收敛-约束原理的岩质隧道初衬安全系数计算[J]. 常州大学学报(自然科学版),2021,33(1):85-92. (Liu Shaofeng, Liu Yun, Su Yonghua. Calculation method for safety factor of primary lining of rock tunnel based on convergence-confirmment principle[J]. Journal of Changzhou University (Natural Science Edition), 2021,33(1):85-92. (in Chinese))
[10] 房倩,杜建明,王赶,等.模型边界对圆形隧道开挖引起地表沉降的影响分析[J]. 隧道与地下工程灾害防治,2022,4(1):10-17. (Fang Qian, Du Jianming, Wang Gan, et al. Influence of model boundary on ground settlement caused by excavation of a circular tunnel[J]. Hazard Control in Tunnelling and Underground Engineering, 2022,4(1):10-17. (in Chinese))
[11] Shen B, Barton N. The disturbed zone around tunnels in jointed rock masses[J]. International Journal of Rock Mechanics and Mining Sciences, 1997, 34(1): 117-126.
[12] Saiang D, Nordlund E. Numerical analyses of the influence of blast-induced damaged rock around shallow tunnels in brittle rock[J]. Rock Mechanics and Rock Engineering, 2009, 42: 421-448.
[13] Li X, Li X F, Zhang Q B, et al.A numerical study of spalling and related rockburst under dynamic disturbance using a particle-based numerical manifold method (PNMM)[J]. Tunnelling and Underground Space Technology, 2018, 81: 438-449.
[14] Timoshenko S, Goodier J N. Theory of elasticity[M]. New York, USA: McGraw-Hill, 1951.
[15] Manouchehrian A, Cai M. Numerical modeling of rockburst near fault zones in deep tunnels[J]. Tunnelling and Underground Space Technology, 2018, 80: 164-180.
[16] Xu X, Wu Z, Sun H, et al.An extended numerical manifold method for simulation of grouting reinforcement in deep rock tunnels[J]. Tunnelling and Underground Space Technology, 2021, 115: 104020.
[17] Carranza-Torres C. Dimensionless graphical representation of the exact elasto-plastic solution of a circular tunnel in a Mohr-Coulomb material subject to uniform far-field stresses[J]. Rock Mechanics and Rock Engineering, 2003, 36(3): 237.
[18] Labuz J F, Zang A. Mohr-Coulomb failure criterion[J]. Rock Mechanics and Rock Engineering, 2012, 45: 975-979.
[19] 刘佑荣, 唐辉明. 岩体力学[M]. 武汉:中国地质大学出版社, 1999. (Liu Yourong, Tang Huiming. Rockmass mechanics[M]. Wuhan: China University of Geosciences Press, 1999. (in Chinese))
[20] Zareifard M R, Fahimifar A. Analytical solutions for the stresses and deformations of deep tunnels in an elastic-brittle-plastic rock mass considering the damaged zone[J]. Tunnelling and Underground Space Technology, 2016, 58: 186-196.
[21] Kastner H.隧道与坑道静力学[M]. 同济大学译. 上海: 上海科学技术出版社, 1980. (Kastner H. Statik Destunnel-und Stollenbaues[M]. Translated by Tongji University. Shanghai: Shanghai Scientific & Technical Publishers, 1980. (in Chinese))
[22] Chang S H, Lee C I. Estimation of cracking and damage mechanisms in rock under triaxial compression by moment tensor analysis of acoustic emission[J]. International Journal of Rock Mechanics and Mining Sciences, 2004, 41(7): 1069-1086.
[23] Su Y, Su Y, Zhao M, et al. Tunnel stability analysis in weak rocks using the convergence confinement method[J]. Rock Mechanics and Rock Engineering, 2021, 54: 559-582.
[24] 中华人民共和国住房和城乡建设部. 工程岩体分级标准(GB/T50218—2014)[S].北京:中国计划出版社, 2015(Ministry of Housing and Urban-Rural Development of the People's Republic of China. Standard for classification of engineering rock masses[S]. Beijing: China Planning Press,2015.(in Chinese))
[25] Vlachopoulos N, Diederichs M S. Appropriate uses and practical limitations of 2D numerical analysis of tunnels and tunnel support response[J]. Geotechnical and Geological Engineering, 2014, 32: 469-488.
[26] Fang Q, Wang G, Yu F, et al. Analytical algorithm for longitudinal deformation profile of a deep tunnel[J]. Journal of Rock Mechanics and Geotechnical Engineering, 2021, 13(4): 845-854.
[27] Ren G, Smith J V, Tang J W, et al. Underground excavation shape optimizationusing an evolutionary procedure[J]. Computers and Geotechnics, 2005, 32(2): 122-132.
