Numerical study on crack propagation of rock mass using the time sequence controlled and notched blasting method

In order to model the mechanical behavior of joints efficiently, a thin-layer tri-node joint element is constructed. The stiffness matrix of the element is derived in the paper. For it shares the common nodes with the original tri-node triangle element, the tri-node joint element can be applied to model the crack propagation without remeshing or mesh adjustment. Another advantage is that the cracked body is meshed without consideration of its geometry integrity and existence of the joints or pre-existed crack in the procedure of mesh generation, and then the triangular element intersected by the crack or joint is automatically transformed into the tri-node joint element to represent pre-existed cracks. These make the numerical simulation of crack propagation highly convenient and efficient. After CZM is chosen to model the crack tip, the mixed- energy simple criterion is used to determine whether the element is intersected by the extended crack or not, the extended crack is located in the model. By modeling the marble plates with two edge cracks subjected to the uniaxial compressive loads, it is shown that the numerical results are in good agreement with the experimental results, which suggests that the present method is valid and feasible in modeling rock crack propagation.

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Numerical study of crack propagation in an indented rock specimen

Computers and Geotechnics ◽

10.1016/j.compgeo.2017.10.014 ◽

2018 ◽

Vol 96 ◽

pp. 1-11 ◽

Cited By ~ 7

Author(s):

Jie Liu ◽

Jun Wang ◽

Wen Wan

Keyword(s):

Crack Propagation ◽

Rock Specimen ◽

Numerical Study

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Investigation and analysis on crack propagation of surrounding rock mass in the AiGong Cave of Longyou

Ancient Underground Opening and Preservation ◽

10.1201/b19169-26 ◽

2015 ◽

pp. 173-178

Keyword(s):

Rock Mass ◽

Crack Propagation ◽

Surrounding Rock

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Numerical simulation of crack propagation in a rock mass under seepage-stress coupling conditions

Boundaries of Rock Mechanics ◽

10.1201/9780203883204.ch51 ◽

2008 ◽

pp. 273-277

Author(s):

K Zhu ◽

J Li ◽

N Zhuang

Keyword(s):

Numerical Simulation ◽

Rock Mass ◽

Crack Propagation ◽

Coupling Conditions

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Numerical Study on Influence of Joint Characters on Rock Mechanical Parameters

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.201-203.2909 ◽

2011 ◽

Vol 201-203 ◽

pp. 2909-2912

Author(s):

Yan Feng Feng ◽

Tian Hong Yang ◽

Hua Wei ◽

Hua Guo Gao ◽

Jiu Hong Wei

Keyword(s):

Rock Mass ◽

Compression Strength ◽

Numerical Study ◽

Process Analysis ◽

Failure Process ◽

Deformation Modulus ◽

Rock Joints ◽

Structured Surfaces ◽

Trace Length ◽

The Impact

Rock mass is the syntheses composed of kinds of structure and structured surfaces. The joint characters is influencing and controlling the rock mass strength, deformation characteristics and rock mass engineering instability failure in a great degree. Through using the RFPA2D software, which is a kind of material failure process analysis numerical methods based on finite element stress analysis and statistical damage theory, the uniaxial compression tests on numerical model are carried, the impact of the trace length of rock joints and the fault throws on rock mechanics parameters are studied. The results showed that with the gradual increase of trace length,compression strength decreased gradually and its rate of variation getting smaller and smaller, the deformation modulus decreased but the rate of variation larger and larger; with the fault throws increasing, the compression strength first increases and then decreases, when the fault throw is equal to the trace length, the deformation modulus is the largest. When the joint trace length is less than the fault throw, the rate of the deformation modulus is greater than that of trace length, but the deformation modulus was not of regular change.

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Dynamic Indentation Characteristics for Various Spacings and Indentation Depths: A Study Based on Laboratory and Numerical Tests

Advances in Civil Engineering ◽

10.1155/2018/8412165 ◽

2018 ◽

Vol 2018 ◽

pp. 1-12 ◽

Cited By ~ 2

Author(s):

Jie Liu ◽

Wen Wan ◽

Yu Chen ◽

Jun Wang

Keyword(s):

Crack Propagation ◽

Laboratory Tests ◽

Indentation Depth ◽

Numerical Study ◽

Stress Concentrations ◽

Dynamic Indentation ◽

Indentation Force ◽

Numerical Tests ◽

Crack Tips ◽

Rock Specimens

Laboratory and numerical study tests were conducted to investigate the dynamic indentation characteristics for various spacings and indentation depths. First, laboratory tests indicate that the increase in the indentation depth first resulted in enlarged groove volumes, caused by fiercer rock breakages between indentations for a fixed spacing; then, the groove volume slightly increased for further increase in indentation depth, whereas the increase in spacing restrained rock breakages and resulted in shrunken grooves. In addition, the numerical study agreed well with laboratory tests that small chips formed at the shallow part of the rock specimen at the early indentation stage, and then, larger chips formed by the crack propagation at deeper parts of the rock specimens when the indentation depth increased. With further increase in indentation depth, crushed powders instead of chips formed. Moreover, the numerical analysis indicates that crack propagation usually leads to the decrease of the indentation force and the dissipation of the stress concentrations at crack tips, whereas the cessation of crack propagation frequently resulted in the increase of the indentation force and the stress concentrations at crack tip with the increase in indentation depth.

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