Abstract
The present research is focused on the numerical crack coalescence analysis of the micro-cracks and cracks produced during the cutting action of TBM disc cutters. The linear elastic fracture mechanics (LEFM) concepts and the maximum tangential stress criterion are used to investigate the micro crack propagation and its direction underneath the excavating discs. A higher order displacement discontinuity method with quadratic displacement discontinuity elements is used to estimate the stress intensity factors near the crack tips. Rock cutting mechanisms under single and double type discs are simulated by the proposed numerical method. The main purposes of the present modeling are to simulate the chip formation process of indented rocks by single and double discs. The effects of specific disc parameters (except speed) on the thrust force F r, the rolling force F r, and the specific energy E S are investigated. It has been shown that the specific energy (energy required to cut through a unit volume of rock) of the double disc is less than that of the single disc. Crack propagation in rocks under disc cutters is numerically modeled and the optimum ratio of disc spacing S to penetration depth P d (i.e. S/P d ratio) of about 10 is obtained, which is in good agreement with the theoretical and experimental results cited in the literature.
Similar content being viewed by others
References
HOWARTH D F, ROXBORUGH F F. Some fundamental aspects of the use of disc cutters in hard rock excavation [J]. J South Afric Inst Min and Metall, 1982, 11: 309–315.
COOK N GW, HOOD M, TSAI F. Observations of crack growth in hard rock loaded by an indenter [J]. Int J Rock Mech Min Sci & Geomech Abstr, 1984, 21: 97–107.
GUO H, AZIZ N I, SCHMIDT L C. Rock cutting study using linear elastic fracture mechanics [J]. Engineering Fracture Mechanics, 1992, 41: 771–778.
ROSTAMI J, OZDEMIR L. A new model for performance prediction of hard rock TBMs [C]// Proceedings of Rapid Excavation and Tunneling Conference (RETC). Boston, 1993: 793–809.
TAN X C, KOU S Q, LINDQVIST P A. Simulation of rock fragmentation by indenters using DDM and fracture mechanics [C]// AUBERTIN M, HASSANI F, MITRI H. Rock Mechanics, Tools and Techniques. Roterdam: Balkema, 1996.
ACARGLU O, OZDEMIR L, ASBURY B. A fuzzy logic model to predict specific energy requirement for TBM performance prediction [J]. Tunneling Underground Space Technology, 2008, 23: 600–608.
BILGIN N, BALACI C, ACAROGLU Ö, TUNCDEMIR H, ESKIKAYA Ş. Development of rapid excavation technologies for the Turkish mining and tunnelling industries [C]// NATO T U. Excavation Project Report. Turkey: Istanbul Technical University, 2000: 172.
BENARDOS A G, KALIAMPAKOS D C. Modeling TBM performance with artificial neural networks [J]. Tunneling and Underground Space Technology, 2004, 19: 597–605.
PARK K I, CHANG S H, CHOI S W, JEON S. Prediction of the optimum cutting condition of TBM disc cutter in Korean granite by the linear cutting test [C]// Proceedings of Korean Society for Rock Mechanics Conference. 2006: 217–236. (in Korean)
FATEHI MARJI M. Crack propagation modeling in rocks and its application to indentation problems [D]. Ankara, Turkey: Middle East Technical University, 1990.
GERTSCH R, GERTSCH L, ROSTAMI J. Disc cutting tests in Colorado red granite: Implications for TBM performance prediction [J]. Int J Rock Mech Min Sci, 2007, 44(2): 238–246.
ALEHOSSEIN H, DETOURNAY E, HUANG H. An analytical model for the indentation of rocks by blunt tools [J]. Rock Mech Rock Engin, 2000, 33: 267–284.
HAERI H, SHAHRIAR K, FATEHI MARJI M, MOAREFVAND P. A coupled numerical-experimental study of the breakage process of brittle substances [J]. Arabian Journal of Geosciences, 2013, DOI:10.1007/s12517-013-1165-1.
FATEHI MARJI M. Modeling of cracks in rock fragmentation with a higher order displacement discontinuity method [D]. Ankara: Middle East Technical University (METU), 1997.
FATEHI MARJI M, HOSSEINI-NASAB H, HOSSEINMORSHEDY A. Numerical modeling of the mechanism of crack propagation in rocks under TBM disc cutters [J]. J Mech Mater Struct, 2009, 2: 439–457.
SHOU K J, CROUCH S L. A higher order displacement discontinuity method for analysis of crack problems [J]. Int J Rock Mech Min Sci & Geomech Abstr, 1995, 32: 49–55.
HAERI H, SHAHRIAR K, FATEHI MARJI M, MOAREFVAND P. An experimental and numerical study of crack propagation and cracks coalescence in the pre-cracked rock-like disc specimens under compression [J]. International Journal of Rock Mechanics and Mining Sciences, 2014, DOI: 10.1016/j.ijmms.2014.01.008.
CROUCH S L, STARFIELD A M. Boundary element methods in solid mechanics [M]. London: Allen and Unwin, 1983.
FATEHI MARJI M, HOSSEINI-NASAB H, KOHSARY A H. On the uses of special crack tip elements in numerical fracture mechanics [J]. Int J Solids Struct, 2006, 43: 1669–1692.
FATEHI MARJI M. Numerical analysis of quasi-static crack branching in brittle solids by a modified displacement discontinuity method [J]. Int J Solids Struct, 2014, 5(19): 1716–1736.
HAERI H, FATEHI MARJI M, SHAHRIAR K, MOAREFVAND P. On the HDD analysis of micro crack initiation, propagation and coalescence in brittle materials [J]. Arabian Journal of Geosciences, 2014, DOI: 10.1007/s12517-014-1290-5.
WHITTAKER B N, SINGH R N, SUN G. Rock fracture mechanics, principles, design and applications [M]. Netherlands: Elsevier, 1992.
BOWIE O L. Solutions of plane crack problems by mapping techniques [C]// SIH G C. Mechanics of Fracture. Leyden: Noordhoff International Publishing, 1973.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Marji, M.F. Simulation of crack coalescence mechanism underneath single and double disc cutters by higher order displacement discontinuity method. J. Cent. South Univ. 22, 1045–1054 (2015). https://doi.org/10.1007/s11771-015-2615-6
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11771-015-2615-6