An experimental study of mechanical behavior of brittle rock-like specimens with multi-non-persistent joints under uniaxial compression and damage analysis

Wendong Yang, Guizhi Li, P. G. Ranjith, Lindong Fang

Research output: Contribution to journalArticleResearchpeer-review

1 Citation (Scopus)

Abstract

The mechanical behavior of jointed rock masses significantly affects the stability of rock engineering applications. In this paper, the peak strength, Young's modulus and failure patterns of brittle rock-like specimens with multi-non-persistent joints under uniaxial compression are investigated. The joint geometry is defined by four factors: joint angle, spacing, joint length, and rock bridge length. The experiment results show that the joint angle has the greatest influence on the peak strength and Young's modulus of specimens, followed by joint length. A damage mechanical theory is adopted which deals with some sets of joints distributed in rock masses. Based on the geometrical distribution of joints, a macro damage model which considers the influence of the normal vector and area density of joints is used to describe the joints. The peak strength and Young's modulus of jointed specimens predicted by the damage mechanics method reflect the trend of the experimental results, which proves the influence of initial geometric damage of joints on the peak strength and Young's modulus of jointed specimens. The initial geometric damage of joints is mainly induced by the joint area density. Finally, from the micro damage aspect, to analyze the damage evolution and strain softening process of jointed rock masses, a modified numerical model (damage strainsofting model) on the basis of secondary development in fast Lagrangian analysis of Continua is proposed to simulate the fracture development of jointed rock masses. The peak strengths, Young's modulus and failure modes of rock specimens with non-persistent joints under uniaxial compressions are simulated and compared with the results obtained from the lab experiments indicating that the model is capable to replicate the physical processes.

Original languageEnglish
Number of pages33
JournalInternational Journal of Damage Mechanics
DOIs
Publication statusAccepted/In press - 19 Feb 2019

Keywords

  • Non-persistent joints
  • peak strength
  • rock-like material
  • strain softening
  • uniaxial compression

Cite this

@article{b709335f1aeb408a94f6b2535b193b05,
title = "An experimental study of mechanical behavior of brittle rock-like specimens with multi-non-persistent joints under uniaxial compression and damage analysis",
abstract = "The mechanical behavior of jointed rock masses significantly affects the stability of rock engineering applications. In this paper, the peak strength, Young's modulus and failure patterns of brittle rock-like specimens with multi-non-persistent joints under uniaxial compression are investigated. The joint geometry is defined by four factors: joint angle, spacing, joint length, and rock bridge length. The experiment results show that the joint angle has the greatest influence on the peak strength and Young's modulus of specimens, followed by joint length. A damage mechanical theory is adopted which deals with some sets of joints distributed in rock masses. Based on the geometrical distribution of joints, a macro damage model which considers the influence of the normal vector and area density of joints is used to describe the joints. The peak strength and Young's modulus of jointed specimens predicted by the damage mechanics method reflect the trend of the experimental results, which proves the influence of initial geometric damage of joints on the peak strength and Young's modulus of jointed specimens. The initial geometric damage of joints is mainly induced by the joint area density. Finally, from the micro damage aspect, to analyze the damage evolution and strain softening process of jointed rock masses, a modified numerical model (damage strainsofting model) on the basis of secondary development in fast Lagrangian analysis of Continua is proposed to simulate the fracture development of jointed rock masses. The peak strengths, Young's modulus and failure modes of rock specimens with non-persistent joints under uniaxial compressions are simulated and compared with the results obtained from the lab experiments indicating that the model is capable to replicate the physical processes.",
keywords = "Non-persistent joints, peak strength, rock-like material, strain softening, uniaxial compression",
author = "Wendong Yang and Guizhi Li and Ranjith, {P. G.} and Lindong Fang",
year = "2019",
month = "2",
day = "19",
doi = "10.1177/1056789519832651",
language = "English",
journal = "International Journal of Damage Mechanics",
issn = "1056-7895",
publisher = "SAGE Publications Ltd",

}

An experimental study of mechanical behavior of brittle rock-like specimens with multi-non-persistent joints under uniaxial compression and damage analysis. / Yang, Wendong; Li, Guizhi; Ranjith, P. G.; Fang, Lindong.

In: International Journal of Damage Mechanics, 19.02.2019.

Research output: Contribution to journalArticleResearchpeer-review

TY - JOUR

T1 - An experimental study of mechanical behavior of brittle rock-like specimens with multi-non-persistent joints under uniaxial compression and damage analysis

AU - Yang, Wendong

AU - Li, Guizhi

AU - Ranjith, P. G.

AU - Fang, Lindong

PY - 2019/2/19

Y1 - 2019/2/19

N2 - The mechanical behavior of jointed rock masses significantly affects the stability of rock engineering applications. In this paper, the peak strength, Young's modulus and failure patterns of brittle rock-like specimens with multi-non-persistent joints under uniaxial compression are investigated. The joint geometry is defined by four factors: joint angle, spacing, joint length, and rock bridge length. The experiment results show that the joint angle has the greatest influence on the peak strength and Young's modulus of specimens, followed by joint length. A damage mechanical theory is adopted which deals with some sets of joints distributed in rock masses. Based on the geometrical distribution of joints, a macro damage model which considers the influence of the normal vector and area density of joints is used to describe the joints. The peak strength and Young's modulus of jointed specimens predicted by the damage mechanics method reflect the trend of the experimental results, which proves the influence of initial geometric damage of joints on the peak strength and Young's modulus of jointed specimens. The initial geometric damage of joints is mainly induced by the joint area density. Finally, from the micro damage aspect, to analyze the damage evolution and strain softening process of jointed rock masses, a modified numerical model (damage strainsofting model) on the basis of secondary development in fast Lagrangian analysis of Continua is proposed to simulate the fracture development of jointed rock masses. The peak strengths, Young's modulus and failure modes of rock specimens with non-persistent joints under uniaxial compressions are simulated and compared with the results obtained from the lab experiments indicating that the model is capable to replicate the physical processes.

AB - The mechanical behavior of jointed rock masses significantly affects the stability of rock engineering applications. In this paper, the peak strength, Young's modulus and failure patterns of brittle rock-like specimens with multi-non-persistent joints under uniaxial compression are investigated. The joint geometry is defined by four factors: joint angle, spacing, joint length, and rock bridge length. The experiment results show that the joint angle has the greatest influence on the peak strength and Young's modulus of specimens, followed by joint length. A damage mechanical theory is adopted which deals with some sets of joints distributed in rock masses. Based on the geometrical distribution of joints, a macro damage model which considers the influence of the normal vector and area density of joints is used to describe the joints. The peak strength and Young's modulus of jointed specimens predicted by the damage mechanics method reflect the trend of the experimental results, which proves the influence of initial geometric damage of joints on the peak strength and Young's modulus of jointed specimens. The initial geometric damage of joints is mainly induced by the joint area density. Finally, from the micro damage aspect, to analyze the damage evolution and strain softening process of jointed rock masses, a modified numerical model (damage strainsofting model) on the basis of secondary development in fast Lagrangian analysis of Continua is proposed to simulate the fracture development of jointed rock masses. The peak strengths, Young's modulus and failure modes of rock specimens with non-persistent joints under uniaxial compressions are simulated and compared with the results obtained from the lab experiments indicating that the model is capable to replicate the physical processes.

KW - Non-persistent joints

KW - peak strength

KW - rock-like material

KW - strain softening

KW - uniaxial compression

UR - http://www.scopus.com/inward/record.url?scp=85061989950&partnerID=8YFLogxK

U2 - 10.1177/1056789519832651

DO - 10.1177/1056789519832651

M3 - Article

JO - International Journal of Damage Mechanics

JF - International Journal of Damage Mechanics

SN - 1056-7895

ER -