An appraisal of Fracture Mechanism of Pseudo-Rock Samples using Brazilian Test

Authors

1 M.Sc of Rock Mechanic Student, School of Mining Engineering, College of Engineering, University of Tehran

2 Professor, School of Mining Engineering, College of Engineering, University of Tehran

Abstract

Characterisation of the deformation behavior of the brittle rocks during loading plays a significant role on rock damage growth. There are a variety approaches to monitor the damage development. Among which the method of Acoustic Emission, due to its accountability, has attracted many researchers’ attention in recent years. The paper describes fracture mechanism of pseudo-rock samples by using Brazilian Test results. Hence, evolution of crack growth and its effect on tensile strength is the prime objective of this research. The work has been performed numerically by using UDEC (Universal Distinct Element Method) and RFPA (Rock Failure Process Analysis) for DEM and FEM analyzes, respectively. The effect of size and position of the artificial voids in disc-type samples on their tensile strength have been investigated. On this basis, several numerical models were constructed and analyzed. Typically, tensile cracks were initiated at the bottom or at the top of the voids, and then propagated parallel to the loading axis and finally reached to the sample surface. The results obtained by numerical methods have been compared with those obtained by Brazilian laboratory tests. Crack initiation, propagation, and coalescence produced by the numerical models have proven very good conformity with the experimental tests’ results. Finally, it has been concluded that by increasing the porosity, the corresponding tensile strength, count, and energy required to brick the rock will decrease exponentially. However, due to plane strain analysis of numerical software, tensile strength is estimated less than that obtained experimentally.

Keywords

References

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Journal of Mineral Resources Engineering
Volume 2, Issue 4
March 2018
Pages 39-52

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History

  • Receive Date: 20 June 2018
  • Accept Date: 20 June 2018

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