Quasi-static and dynamic fracture behaviour of rock materials: phenomena and mechanisms

An experimental investigation is conducted to study the quasi-static and dynamic fracture behaviour of sedimentary, igneous and metamorphic rocks. The notched semi-circular bending method has been employed to determine fracture parameters over a wide range of loading rates using both a servo-hydraulic machine and a split Hopkinson pressure bar. The time to fracture, crack speed and velocity of the flying fragment are measured by strain gauges, crack propagation gauge and high-speed photography on the macroscopic level. Dynamic crack initiation toughness is determined from the dynamic stress intensity factor at the time to fracture, and dynamic crack growth toughness is derived by the dynamic fracture energy at a specific crack speed. Systematic fractographic studies on fracture surface are carried out to examine the micromechanisms of fracture. This study reveals clearly that: (1) the crack initiation and growth toughness increase with increasing loading rate and crack speed; (2) the kinetic energy of the flying fragments increases with increasing striking speed; (3) the dynamic fracture energy increases rapidly with the increase of crack speed, and a semi-empirical rate-dependent model is proposed; and (4) the characteristics of fracture surface imply that the failure mechanisms depend on loading rate and rock microstructure.

[1]  John G. Spray,et al.  Dynamic fragmentation of granite for impact energies of 6–28 J , 2012 .

[2]  Louis Ngai Yuen Wong,et al.  Fracturing and Failure Behavior of Carrara Marble in Quasistatic and Dynamic Brazilian Disc Tests , 2014, Rock Mechanics and Rock Engineering.

[3]  Per-Arne Lindqvist,et al.  Effects of loading rate on rock fracture , 1999 .

[4]  Yingxin Zhou,et al.  Rock dynamics research related to cavern development for Ammunition storage , 1999 .

[5]  M. Kuruppu Fracture toughness measurement using chevron notched semi-circular bend specimen , 1997 .

[6]  L. Ponson,et al.  Failure mechanisms and surface roughness statistics of fractured Fontainebleau sandstone. , 2007, Physical review. E, Statistical, nonlinear, and soft matter physics.

[7]  C. Atkinson,et al.  Combined mode fracture via the cracked Brazilian disk test , 1982, International Journal of Fracture.

[8]  K. Thoma,et al.  Spall experiments for the measurement of the tensile strength and fracture energy of concrete at high strain rates , 2006 .

[9]  Brian Lawn,et al.  Fracture of brittle solids: Atomic aspects of fracture , 1993 .

[10]  Albert S. Kobayashi,et al.  Fracture Process Zone for Concrete for Dynamic Loading , 1992 .

[11]  R. Alley,et al.  Finite element analysis of the modified ring test for determining mode I fracture toughness , 1996 .

[12]  Q. Wang,et al.  Measurement of mode I and mode II rock dynamic fracture toughness with cracked straight through flattened Brazilian disc impacted by split Hopkinson pressure bar , 2011 .

[13]  K. Xia,et al.  A Semi-Circular Bend Technique for Determining Dynamic Fracture Toughness , 2010 .

[14]  G. Ruiz,et al.  Effect of loading rate on crack velocities in HSC , 2010 .

[15]  T. Hsu,et al.  Fracture toughness of coal under quasi-static and impact loading , 1984 .

[16]  J. Knott,et al.  Micromechanisms of brittle fracture , 1993 .

[17]  Elisabeth Bouchaud,et al.  Failure of heterogeneous materials: A dynamic phase transition? , 2011 .

[18]  Ove Stephansson,et al.  Effect of loading rate on Mode I fracture toughness, roughness and micromechanics of sandstone , 2003 .

[19]  Qianbing Zhang,et al.  Determination of mechanical properties and full-field strain measurements of rock material under dynamic loads , 2013 .

[20]  H. Xie,et al.  Rock Dynamic Fracture Toughness Tested with Holed-Cracked Flattened Brazilian Discs Diametrically Impacted by SHPB and its Size Effect , 2010 .

[21]  David E. Lambert,et al.  Strain rate effects on dynamic fracture and strength , 2000 .

[22]  B. Atkinson Fracture Mechanics of Rock , 1987 .

[23]  K. Ravi-Chandar,et al.  An experimental investigation into dynamic fracture: II. Microstructural aspects , 1984 .

[24]  D. Sanderson,et al.  Fractal effects of crack propagation on dynamic stress intensity factors and crack velocities , 1996 .

[25]  Luigi Burlini,et al.  Damage and recovery of calcite rocks deformed in the cataclastic regime , 2004, Geological Society, London, Special Publications.

[26]  John D. Clayton,et al.  Deformation, fracture, and fragmentation in brittle geologic solids , 2010 .

[27]  Y. Nara,et al.  Subcritical crack growth and long-term strength in rock and cementitious material , 2010 .

[28]  Fangyun Lu,et al.  Determination of dynamic fracture parameters using a semi-circular bend technique in split Hopkinson pressure bar testing , 2009 .

[29]  K. Xia,et al.  Evaluation of the frictional effect in dynamic notched semi-circular bend tests , 2013 .

[30]  J. Kalthoff Fracture behavior under high rates of loading , 1986 .

[31]  M. G. Norton,et al.  Stress-dependent morphological features on fracture surfaces of quartz and glass , 1981 .

[32]  B. Mohanty,et al.  Fracture toughness anisotropy in granitic rocks , 2008 .

[33]  Xibing Li,et al.  Numerical Simulation of the Rock SHPB Test with a Special Shape Striker Based on the Discrete Element Method , 2014, Rock Mechanics and Rock Engineering.

[34]  L. Costin,et al.  Static and Dynamic Fracture Behavior of Oil Shale , 1981 .

[35]  D. Grady,et al.  Strain-rate dependent fracture initiation , 1980 .

[36]  Zdeněk P. Bažant,et al.  Fracture of rock: Effect of loading rate , 1993 .

[37]  Y. Obara,et al.  ISRM-Suggested Method for Determining the Mode I Static Fracture Toughness Using Semi-Circular Bend Specimen , 2013, Rock Mechanics and Rock Engineering.

[38]  K. Ravi-Chandar,et al.  An experimental investigation into dynamic fracture: I. Crack initiation and arrest , 1984 .

[39]  Hongwei Zhou,et al.  Direct Estimation of the Fractal Dimensions of a Fracture Surface of Rock , 2003 .

[40]  Yaodong Jiang,et al.  Experimental and numerical modelling investigation on fracturing in coal under impact loads , 2013, International Journal of Fracture.

[41]  Jean-François Molinari,et al.  A rate-dependent cohesive model for simulating dynamic crack propagation in brittle materials , 2005 .

[42]  R. Kranz Microcracks in rocks: a review , 1983 .

[43]  L. Wong,et al.  Loading rate effects on cracking behavior of flaw-contained specimens under uniaxial compression , 2013, International Journal of Fracture.

[44]  Z. T. Bieniawski,et al.  Brittle fracture propagation in rock under compression , 1965 .

[45]  Jian Zhao,et al.  A Review of Dynamic Experimental Techniques and Mechanical Behaviour of Rock Materials , 2014, Rock Mechanics and Rock Engineering.

[46]  R. J. Fowell,et al.  Suggested method for determining mode I fracture toughness using Cracked Chevron Notched Brazilian Disc (CCNBD) specimens , 1995 .

[47]  Xibing Li,et al.  Dynamic Characteristics of Granite Subjected to Intermediate Loading Rate , 2005 .

[48]  K. Ravi-Chandar,et al.  An experimental investigation into dynamic fracture: III. On steady-state crack propagation and crack branching , 1984 .

[49]  Cai-ping Liu,et al.  Meso-structure analysis on instability of dynamic fracture in rock , 2010, International Conference on Experimental Mechanics.

[50]  A. Rosakis,et al.  Loading Rates and the Dynamic Initiation Toughness in Brittle Solids , 1998 .

[51]  Kenneth S. Vecchio,et al.  Hopkinson Bar Loaded Fracture Experimental Technique: A Critical Review of Dynamic Fracture Toughness Tests , 2009 .

[52]  A. S. Eremenko,et al.  Determination of fracture toughness and fracture energy of brittle materials under impact wedging , 1996 .

[53]  K. Ravi-Chandar,et al.  On the role of microcracks in the dynamic fracture of brittle materials , 1997 .

[54]  A. Bertram,et al.  Crack Propagation Toughness of Rock for the Range of Low to Very High Crack Speeds , 2003 .

[55]  D. Kun,et al.  CRITICAL FAILURE CHARACTERISTICS OF HIGH STRESS ROCK INDUCED BY IMPACT DISTURBANCE UNDER CONFINING PRESSURE UNLOADING , 2012 .

[56]  Z. T. Bieniawski,et al.  Brittle fracture propagation in rock under compression , 1965 .

[57]  L. Rose Effective Fracture Toughness of Microcracked Materials , 1986 .

[58]  Y. X. Wang,et al.  Determination of dynamic rock Mode-I fracture parameters using cracked chevron notched semi-circular bend specimen , 2011 .

[59]  W. Fourney,et al.  On the uniqueness of the stress intensity factor — crack velocity relationship , 1985 .

[60]  K. T. Ramesh,et al.  The Compressive Failure of Aluminum Nitride Considered as a Model Advanced Ceramic , 2011 .

[61]  Z. Yue,et al.  Dynamic fracture behavior of rock under impact load using the caustics method , 2009 .

[62]  Jian Zhao,et al.  Effect of loading rate on fracture toughness and failure micromechanisms in marble , 2013 .

[63]  Ezio Cadoni,et al.  Dynamic Characterization of Orthogneiss Rock Subjected to Intermediate and High Strain Rates in Tension , 2010 .

[64]  Anthony R. Ingraffea,et al.  SUGGESTED METHODS FOR DETERMINING THE FRACTURE TOUGHNESS OF ROCK. , 1988 .

[65]  P. Forquin An optical correlation technique for characterizing the crack velocity in concrete , 2012 .

[66]  Gao-Feng Zhao,et al.  Dynamic Indirect Tensile Strength of Sandstone Under Different Loading Rates , 2014, Rock Mechanics and Rock Engineering.

[67]  H. Xie,et al.  Erratum to: Rock Dynamic Fracture Toughness Tested with Holed-Cracked Flattened Brazilian Discs Diametrically Impacted by SHPB and its Size Effect , 2010 .

[68]  Per-Arne Lindqvist,et al.  Effects of loading rate on rock fracture: fracture characteristics and energy partitioning , 2000 .

[69]  Sidney Mindess,et al.  The fracture toughness of concrete under impact loading , 1987 .

[70]  J. J. Mecholsky,et al.  Fractal analysis of fracture in Ocala chert , 1988 .

[71]  J. E. Field,et al.  Brittle Fracture: its Study and Application , 1971 .

[72]  K. Xia,et al.  Dynamic cracked chevron notched Brazilian disc method for measuring rock fracture parameters , 2010 .

[73]  Josef Eibl,et al.  Crack velocity in concrete , 1990 .

[74]  Yang Ju,et al.  Study on stress wave propagation in fractured rocks with fractal joint surfaces , 2007 .

[75]  J. Foster,et al.  Dynamic crack initiation toughness of 4340 steel at constant loading rates , 2011 .

[76]  Xibing Li,et al.  Suggested Methods for Determining the Dynamic Strength Parameters and Mode-I Fracture Toughness of Rock Materials , 2012 .

[77]  K. Clarke Computation of the fractal dimension of topographic surfaces using the triangular prism surface area method , 1985 .

[78]  Bengt Lundberg,et al.  A split Hopkinson bar study of energy absorption in dynamic rock fragmentation , 1976 .

[79]  I. L. Lim,et al.  Stress intensity factors for semi-circular specimens under three-point bending , 1993 .

[80]  Z. Bieniawski Fracture dynamics of rock , 1968 .

[81]  Y. Chao,et al.  Effect of loading rate on dynamic fracture initiation toughness of brittle materials , 2007 .

[82]  R. Bradt,et al.  Single crystal cleavage of brittle materials , 1994 .

[83]  Yoshiaki Yamauchi,et al.  Dynamic fracture initiation in brittle materials under combined mode I/II loading , 1994 .

[84]  Chun’an Tang,et al.  A new method for measuring dynamic fracture toughness of rock , 1990 .