Analysis of impact-induced rock fragmentation using a discrete element approach

Shen, Weigang; Zhao, Tao; Crosta, Giovanni B.; Dai, Feng

doi:10.1016/j.ijrmms.2017.07.014

Cited by 73 publications

(33 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The current study considers this setting for numerical simulations by the discrete element method (DEM) (Cundall & Strack, 1979). The DEM has been widely employed as a tool for numerical modelling of rock avalanches and solid breakages (Boon et al, 2014(Boon et al, , 2015bCalvetti et al, 2000;Fu et al, 2017;Shen et al, 2017;Taboada & Estrada, 2009;Timár et al, 2012;Zhao et al, 2014Zhao et al, , 2016Zhao et al, , 2017. As stated by Alassi and Holt (2012), the method is capable of modeling complex dynamic responses of rock mass, such as crack initiation and propagation.…”

Section: Introductionmentioning

confidence: 99%

Dynamic Fragmentation of Jointed Rock Blocks During Rockslide‐Avalanches: Insights From Discrete Element Analyses

et al. 2018

Self Cite

View full text Add to dashboard Cite

The dynamic fragmentation of jointed rock blocks during rockslide avalanches has been investigated by discrete element method simulations for a multiple arrangement of a rock block sliding over a simple slope geometry. The rock blocks are released along an inclined sliding plane and subsequently collide onto a flat horizontal plane at a sharp kink point. The contact force chains generated by the impact appear initially at the bottom frontal corner of the rock block and then propagate radially upward to the top rear part of the block. The jointed rock blocks exhibit evident contact force concentration and discontinuity of force wave propagation near the joint, associating with high energy dissipation of granular dynamics. The corresponding force wave propagation velocity can be less than 200 m/s, which is much smaller than that of an intact rock (1,316 m/s). The concentration of contact forces at the bottom leads to high rock fragmentation intensity and momentum boosts, facilitating the spreading of many fine fragments to the distal ends. However, the upper rock block exhibits very low rock fragmentation intensity but high energy dissipation due to intensive friction and damping, resulting in the deposition of large fragments near the slope toe. The size and shape of large fragments are closely related to the orientation and distribution of the block joints. The cumulative fragment size distribution can be well fitted by the Weibull's distribution function, with very gentle and steep curvatures at the fine and coarse size ranges, respectively. The numerical results of fragment size distribution can match well some experimental and field observations.

show abstract

Section: Introductionmentioning

confidence: 99%

Dynamic Fragmentation of Jointed Rock Blocks During Rockslide‐Avalanches: Insights From Discrete Element Analyses

et al. 2018

Self Cite

View full text Add to dashboard Cite

show abstract

“…According to (1) and (2), the cutting torque, rotation speed, pulling force, drilling depth, cutting time, mass, and volume of the crushed rock are necessary to measure. e rock density is a physical and mechanical property that is easily obtained.…”

Section: Advances In Materials Science and Engineeringmentioning

confidence: 99%

“…Additionally, the drilling depth of a cutting head can also re ect the rock fragmentation by that cutting head with a constant power hydraulic system. According to (1) and (2), the three types of SE (H w , H r , and H h ) were calculated through the integration of the cutting torque versus time and pulling force versus drilling depth before the peak values. e SE and drilling depth of the rock fragmentation are listed in Table 2 and are shown in Figures 6 and 7 with di erent R CS .…”

Section: Se Without Waterjetmentioning

confidence: 99%

See 1 more Smart Citation

Experimental Research on the Specific Energy Consumption of Rock Breakage Using Different Waterjet‐Assisted Cutting Heads

Jiang

Meng

2018

Advances in Materials Science and Engineering

View full text Add to dashboard Cite

To investigate the specific energy consumption (SE) of rock breakage by cutting heads assisted by different types of waterjet and to identify optimal waterjet parameters and assistance types, rock cutting with and without waterjets was carried on a rock fragmentation test bed. SE is a comprehensive evaluation index and was developed according to the applied load on cutting head, and the SE under different cutting conditions was compared and analyzed. e results show that the SE of rock breakage without waterjet assistance increased with the increasing of rock compressive strength (R CS ) but that the limited drilling depth decreased.e effect of the waterjet pressure on the SE of rock breakage by the cutting head I was marked, and SE decreased by 30∼40% when the ratio between R CS and waterjet pressure was less than 1. However, the function of the waterjet assistance was poor; therefore, a ratio of 1 could be used to distinguish the rock breakage effect of cutting head I. For cutting head II, the rock damage from the waterjet impact was limited due to the large waterjet standoff distance; thus the rock breakage performance of cutting head II was also limited. e waterjet impacting at the tip of the conical pick using cutting head III could enter into the cracks caused by the mechanical pick and fracture the rock. erefore, the rock breakage performance of cutting head III was better than that of cutting head II.

show abstract

“…On the other hand, the discontinuity of rock mass can be conveniently investigated by the discrete element method (DEM). It has been employed widely to analyze the brittle failure of solid materials, for example, rock fragmentation, 13,14 particle crushing, 15,16 and damage of cemented geomaterials, 7,17 because of its capability of modeling the complex brittle responses of solid mass under external loadings, such as crack initiation and propagation 18,19 . At failure, the internal fractures propagate and nucleate rapidly within the solid mass because of the breakage of interparticle cementations (ie, bonds).…”

Section: Introductionmentioning

confidence: 99%

A novel random discrete element analysis of rock fragmentation

Zhao

Liu

2020

Num Anal Meth Geomechanics

Self Cite

View full text Add to dashboard Cite

This paper presents a novel probabilistic approach of random discrete element analysis (RDEA) to investigate the mechanism of rock fragmentation under uniaxial compression. This model combines the advantages of both random field theory and discrete element method in characterizing the spatial variation and uncertainty of microscopic material properties. The numerical results reveal that the stress-strain curves of a group of tests can match well the general trend of the experimental data, with the mean uniaxial compressive strength (UCS) of 10.18 MPa and the mean Young modulus of 1.73 GPa. The coefficient of variation (COV) for the rock samples is much lower than that of the initial random fields of particles because of the averaging effect of microscopic material property in obtaining the bulk values. The rock fragmentation is initiated by the breakage of weak particles within the rock mass, and it develops rapidly as the vertical loading stress approaches the UCS. The final damage zone resides dominantly in the weak region of the rock sample, and the distribution of material property coefficients follows a similar beta distribution as the corresponding initial random field. Rock samples with persistent "pillar-like" structures of strong particles can effectively resist the normal compression, resulting in high rock strengths.The traditional DEM simulation with a set of constant material properties can only represent one extreme realization of random field, which could significantly overestimate the rock strength. The proposed RDEA approach can effectively capture the uncertainty and complex interactions of rock fragmentation in a more realistic and reliable way. K E Y W O R D Sbrittle failure, DEM, random field, rock fragmentation, uniaxial compression

show abstract

Analysis of impact-induced rock fragmentation using a discrete element approach

Cited by 73 publications

References 33 publications

Dynamic Fragmentation of Jointed Rock Blocks During Rockslide‐Avalanches: Insights From Discrete Element Analyses

Dynamic Fragmentation of Jointed Rock Blocks During Rockslide‐Avalanches: Insights From Discrete Element Analyses

Experimental Research on the Specific Energy Consumption of Rock Breakage Using Different Waterjet‐Assisted Cutting Heads

A novel random discrete element analysis of rock fragmentation

Contact Info

Product

Resources

About