Brittle Rock Modeling Approach and its Validation Using Excavation-Induced Micro-Seismicity

With improvements to the bonded-particle model, a custom indicator of crack intensity is introduced to grade rock fractures accurately. Brittle fracturing of rock mass is studied using the bonded-particle model; here, “brittle” refers to the process where more energy is released towards making particles collide and disperse, and hence results in the quick emergence of “chain cracks”. Certain principles concerning how to construct brittle rock are then proposed. Furthermore, a modeling approach for brittle rocks based on the adaptive continuum/discontinuum (AC/DC) method is proposed to aid the construction of large-scale models of tunnel excavations. To connect with actual tunneling conditions, fundamental mechanical properties, the mechanism for brittle fracturing, the joint distribution, and the initial stress field are considered in the modeling approach. Results from micro-seismic monitoring of a tunnel excavation confirmed the suitability of this modeling approach to simulate crack behavior, and results show that simulated cracking exhibit similar trends (evolution, location, and intensity) with micro-seismic cracking.

[1]  Z. T. Bieniawski,et al.  Mechanism of brittle fracture of rockPart IIexperimental studies , 1967 .

[2]  Z. T. Bieniawski,et al.  Mechanism of brittle fracture of rockPart Itheory of the fracture process , 1967 .

[3]  W. R. Wawersik,et al.  A study of brittle rock fracture in laboratory compression experiments , 1970 .

[4]  J. Chaboche.  Continuum Damage Mechanics: Part I—General Concepts , 1988 .

[5]  Mahmood A. Khwaja,et al.  An ellipse-based discrete element model for granular materials , 1993 .

[6]  N. G. Shrive,et al.  Brittle fracture in compression: Mechanisms, models and criteria , 1995 .

[7]  R. P. Young,et al.  Simulating acoustic emissions in bonded-particle models of rock , 2000 .

[8]  R. P. Young,et al.  Moment tensors and micromechanical models , 2002 .

[9]  P. Cundall,et al.  A bonded-particle model for rock , 2004 .

[10]  Idar Larsen,et al.  Comparison between controlled laboratory experiments and discrete particle simulations of the mechanical behaviour of rock , 2005 .

[11]  C. Martin,et al.  A clumped particle model for rock , 2007 .

[12]  P. A. Cundall,et al.  A Synthetic Rock Mass Model For Jointed Rock , 2007 .

[13]  A. S. Tawadrous,et al.  Prediction of uniaxial compression PFC3D model micro‐properties using artificial neural networks , 2009 .

[14]  Diego Mas Ivars,et al.  Bonded Particle Model for Jointed Rock Mass , 2010 .

[15]  L. Wong,et al.  Cracking Processes in Rock-Like Material Containing a Single Flaw Under Uniaxial Compression: A Numerical Study Based on Parallel Bonded-Particle Model Approach , 2011, Rock Mechanics and Rock Engineering.

[16]  Diego Mas Ivars,et al.  The synthetic rock mass approach for jointed rock mass modelling , 2011 .

[17]  Ireneusz Lapczyk,et al.  Continuum Damage Mechanics , 2012 .

[18]  Ali Tarokh,et al.  Discrete element simulation of the effect of particle size on the size of fracture process zone in quasi-brittle materials , 2014 .

[19]  Guang-yi Ma.  Near-free-defect Laser Welding of AP1000 Nuclear Reactor Coolant Pump Can , 2015 .