A 3D FEM methodology for simulating the impact in rock-drilling hammers

Abstract A three-dimensional (3D) finite element approach for modeling impact as it occurs in impact tools used in rock drilling is presented. The model permits one to simulate the energy transmission to the rock, the bit–rock interaction, and the process of rock fragmentation, all of which are important in the study and evaluation of such tools. The finite elements method (FEM) analysis allows one to simulate the impact in 3D stress–strain problems, to consider linear material properties, and to include post failure fracture propagation. Anisotropic elements have been used to model the rock post failure behavior. Infinite domain elements have been used to characterize boundary conditions far away from bit–rock interaction. The accuracy of the model has been evaluated both theoretically by comparing the result to those obtained with a model based on impulse–momentum principle as well as experimentally.

[1]  Charles Fairhurst,et al.  A theoretical and experimental study of the percussive drilling of rock part III—experimental verification of the mathematical theory , 1972 .

[2]  Gernot Beer,et al.  Numerical methods in rock mechanics , 1990 .

[3]  K. Bathe.  Finite Element Procedures , 1995 .

[4]  Karl-Gustaf Sundin,et al.  Experimental study of a percussive process for rock fragmentation , 1989 .

[5]  Bengt Lundberg,et al.  Computer Modelling and Simulation of Percussive Drilling of Rock , 1993 .

[6]  W. Goldsmith,et al.  A force-indentation model for brittle rocks , 1989 .

[7]  Charles Fairhurst,et al.  A theoretical and experimental study of the percussive drilling of rock Part II—force-penetration and specific energy determinations , 1971 .

[8]  Charles Fairhurst,et al.  A theoretical and experimental study of the percussive drilling of rock Part IV—application of the model to actual percussion drilling , 1972 .

[9]  Tamer M. Wasfy,et al.  Computational procedure for simulating the contact/impact response in flexible multibody systems , 1997 .

[10]  Luciano E. Chiang,et al.  Modeling impact in down-the-hole rock drilling , 2000 .

[11]  O. C. Zienkiewicz,et al.  El método de los elementos finitos , 1981 .

[12]  Karl-Gustaf Sundin,et al.  A method for determination of in-hole dynamic force-penetration data from two-point strain measurement on a percussive drill rod , 1990 .

[13]  T. F. Lehnhoff,et al.  Bit penetration into rockA finite element study , 1976 .

[14]  Wu Changming,et al.  Percussive energy transfer in pneumatic top hammer rock drills , 1991 .

[15]  W. Hustrulid,et al.  A theoretical and experimental study of the percussive drilling of rock part I—theory of percussive drilling , 1971 .

[16]  Ning Hu,et al.  A solution method for dynamic contact problems , 1997 .

[17]  Bengt Lundberg,et al.  MICROCOMPUTER SIMULATION OF PERCUSSIVE DRILLING , 1985 .

[18]  Werner Goldsmith,et al.  Response of rocks to impact loading by bars with pointed ends , 1981 .

[19]  Luciano E. Chiang,et al.  A methodology for estimation of the specific rock energy index using corrected down-the-hole drill monitoring data , 2004 .

[20]  P. W. Christensen,et al.  Formulation and comparison of algorithms for frictional contact problems , 1998 .

[21]  Håkan Schunnesson,et al.  Rock characterisation using percussive drilling , 1998 .

[22]  John A. Hudson,et al.  Comprehensive rock engineering , 1993 .

[23]  G. Clark.  Principles of Rock Fragmentation , 1987 .

[24]  Tim Grant,et al.  Lab investigations of percussion drilling: from single impact to full scale fluid hammer , 2006 .

[25]  W. Z. Ben Wu.  Microcomputer Application For The Efficiency Evaluation Of Percussive Drilling , 1986 .

[26]  Peter Shi.  Simulation of impact involving an elastic rod , 1998 .

[27]  Bengt Lundberg,et al.  Microcomputer simulation of stress wave energy transfer to rock in percussive drilling , 1982 .

[28]  Gang Han,et al.  Dynamically Modelling Rock Failure in Percussion Drilling , 2005 .

[29]  P. Wriggers,et al.  A method for solving contact problems , 1998 .