Abstract
Size and quantity of fractured zone and non-fractured zone are controlled by cracks contained in deep rock masses. Zonal disintegration mechanism is strongly dependent on the interaction among cracks. The strong interaction among cracks is investigated using stress superposition principle and the Chebyshev polynomials expansion of the pseudo-traction. It is found from numerical results that crack nucleation, growth and coalescence lead to failure of deep crack-weakened rock masses. The stress redistribution around the surrounding rock mass induced by unloading excavation is studied. The effect of the excavation time on nucleation, growth, interaction and coalescence of cracks was analyzed. Moreover, the influence of the excavation time on the size and quantity of fractured zone and non-fractured zone was given. When the excavation time is short, zonal disintegration phenomenon may occur in deep rock masses. It is shown from numerical results that the size and quantity of fractured zone increase with decreasing excavation time, and the size and quantity of fractured zone increase with the increasing value of in-situ geostress.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Qian, Q.H., The current development of nonlinear rock mechanicsthe mechanical problems of deep rock mass. In: Chinese Society of Rock Mechanics and Engineering, Proceedings of the 8th Rock Mechanics and Engineering Conference. Beijing: Science Press, 2004, 10–17 (in Chinese).
Cloete, D.R. and Jager, A.J., The nature of the fracture zone in gold mines as revealed by diamond core drilling. Association of Mine Managers, 1972–1973.
Adms, G.R. and Jager, A.J., Petroscopic observations of rock fracturing ahead of stope faces in deep-level gold mine. Journal of the South African Institute of Mining and Metallurgy, 1980, 80(6): 204–209.
Shemyakin, E.I., Fisenko, G.L., Kurlenya, M.V. and Oparin, V.N., Zone disintegration of rocks around underground workings—Part I: Data of in-site observations. Journal of Mining Science, 1986, 22(3): 157–168.
Shemyakin, E.I., Fisenko, G.L., Kurlenya, M.V. and Oparin, V.N., Zone disintegration of rocks around underground workings-Part II: Disintegration of rocks on models of equivalent materials. Journal of Mining Science, 1986, 22(4): 223–232.
Shemyakin, E.I., Fisenko, G.L., Kurlenya, M.V. and Oparin, V.N., Zone disintegration of rocks around underground workings—Part III: Theroetical notions. Jounal of Mining Science, 1987, 23(1): 1–6.
Shemyakin, E.I., Fisenko, G.L., Kurlenya, M.V. and Oparin, V.N., Zone disintegration of rocks around underground workings—Part IV: Practical applications. Jounal of Mining Science, 1988, 24(1): 238–241.
Shemyakin, E.I., Kyrlenya, M.V. and Reva, V.N., Effect of zonal disintegration of rocks around underground workings. USSR, 1986, 289(5): 1088–1094.
Zhou, X.P. and Qian, Q.H., Zonal fracturing mechanism in deep tunnel. Chinese Journal of Rock Mechanics and Engineering, 2007, 26(5): 877–885 (in Chinese).
Mirzaev, G.G., Protosenya, A.G., Ogorodnikow, Y.N. and Vikhorev, V.I., Support Systems of Deep Mines. Moscow: Bedra, 1976 (in Russian).
Cai, M. and Horii, H., A constitutive model and FEM analysis of jointed rock masses. International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, 1993, 30(4): 351–359.
Cai, M., Kaiser, P.K., Tasaka, Y., Maejima, T., Morioka, H. and Minami, M., Generalized crack initiation and crack damage stress thresholds of brittle rock masses near underground excavations. International Journal of Rock Mechanics and Mining Sciences, 2004, 41(5): 833–847.
Zhou, X.P., Wang, F.H., Qian, Q.H. and Zhang, B.H., Zonal fracturing mechanism in deep crack-weakened rock masses. Theoretical and Applied Fracture Mechanics, 2008, 50(1): 57–65.
Zhou, X.P., Qian, Q.H. and Yang, H.Q., Strength criteria of deep rock mass. Chinese Journal of Rock Mechanics and Engineering, 2008, 27(1): 117–123 (in Chinese).
Lo, K.K., Analysis of branched cracks. ASME Journal of Applied Mechanics, 1978, 45: 797–802.
Zhou, X.P., Qian, Q.H. and Zhang, Y.X., The constitutive relation of crack-weakened rock masses under axial-dimensional unloading. Acta Mechanica Solida Sinica, 2008, 21(3): 221–231.
Horii, H. and Nemat-Nasser, S., Brittle failure in compression: splitting, faulting and brittle-ductile transition. Philosophical Transactions of the Royal Society of London, 1986, A319: 337–374.
Niu, J. and Wu, M.S., Analysis of asymmetric kinked cracks of arbitrary size, location and orientation—Part I. Remote Compression. International Journal of Fracture, 1998, 89(1): 19–57.
Muskhelishvili, N.L., Some Basic Problems in the Mathematical Theory of Elasticity. Netherlands: Noordhoff, Groningen, 1953.
Gerasoulis, A., The use of quadratic polynomials for the solution of singular integral equations of cauchy type. Computer & Mathmatics with Applications, 1982, 8(1): 15–22.
Freund,L.B., Dynamic Fracture Mechanics. Cambridge University Press, 1990.
Cherepanov, G.P., Mechanics of Brittle Fracture. New York: Translated by R de Wit and W C Ccoley, McGraw-Hill, 1979.
Author information
Authors and Affiliations
Corresponding author
Additional information
Project supported by the National Natural Science Foundation of China (Nos.50490275 and 50778184).
Rights and permissions
About this article
Cite this article
Zhou, X., Qian, Q. & Zhang, B. Zonal disintegration mechanism of deep crack-weakened rock masses under dynamic unloading. Acta Mech. Solida Sin. 22, 240–250 (2009). https://doi.org/10.1016/S0894-9166(09)60271-8
Received:
Revised:
Published:
Issue Date:
DOI: https://doi.org/10.1016/S0894-9166(09)60271-8