Structural Engineering and Mechanics

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PFC3D simulation of the effect of particle size on the single edge-notched rectangle bar in bending test

  • Haeri, Hadi (MOE Key Laboratory of Deep Underground Science and Engineering, School of Architecture and Environment, Sichuan University) ;
  • Sarfarazi, Vahab (Department of Mining Engineering, Hamedan University of Technology) ;
  • Zhu, Zheming (MOE Key Laboratory of Deep Underground Science and Engineering, School of Architecture and Environment, Sichuan University)
  • Received : 2018.08.02
  • Accepted : 2018.10.11
  • Published : 2018.11.25
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Abstract

Three points bending flexural test was modeled numerically to study the crack propagation in the pre-cracked beams. The pre-existing edge cracks in the beam models were considered to investigate the crack propagation and coalescence paths within the modeled samples. The effects of particle size on the single edge-notched round bar in bending test were considered too. The results show that Failure pattern is constant by increasing the ball diameter. Tensile cracks are dominant mode of failure. These crack initiates from notch tip, propagate parallel to loading axis and coalescence with upper model boundary. Number of cracks increase by decreasing the ball diameter. Also, tensile fracture toughness was decreased with increasing the particle size. In the present study, the influences of particles sizes on the cracks propagations and coalescences in the brittle materials such as rocks and concretes are numerically analyzed by using a three dimensional particle flow code (PFC3D). These analyses improve the understanding of the stability of rocks and concretes structures such as rock slopes, tunnel constructions and underground openings.

Keywords

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