首页
  团队
  研究成果
  -> 发表论文
  -> 科研项目
  -> 获奖情况
  -> 资料下载
  教学
  学术讨论
  在线计算
  联系我们
 
  研究成果
 
Particle crushing simulations with ...
 发布时间:2016/3/29 浏览次数:2117

Particle crushing simulations with improved discontinuous deformation analysis

Abstract: Purpose – Rock-fill dams are embankments of compacted free-draining granular earth containing an  impervious zone. Earth utilized in such dams often contains a high percentage of large particles – hence  the term rock-fill. Mass stability of these dams results from friction and particle interactions rather  than through a cementing agent binding the particles together. However, high-stress conditions  and prolonged exposure to the elements can severely damage rock-fill. Therefore, understanding and  modeling rock-fill breakage is important for dam engineering. The purpose of this paper is to improve  discontinuous deformation analysis (DDA) techniques for modeling rock-fill breakage, proving the  new method using simulations of spherical particle crushing.  Design/methodology/approach – This work models rock-fill as bonded ellipsoid particles, and  develops an improved DDA method to model the breakage of particle assemblies. The paper starts by  describing the principles of three-dimensional DDA for spherical particles, and then derives the  submatrices for normal contact, shear contact, and frictional force. The new algorithm incorporates  a bond model with a revised open-close iteration algorithm into the DDA method to simulate particle  crushing. To validate the improved DDA method, calculated particle contacts and movements are  validated against theoretical results. Finally, this work performs a series of point-loading experimental  tests for cement ellipsoid particles of both high and low compression strengths, with the test results  compared against the results from corresponding DDA simulations.  Findings – In particle crushing tests, the force and displacement show an approximately linear  relationship until the crushing point, at which point low compression ellipsoid particles split into  several large pieces while the high-compression particles break into many small fragments. The DDA  simulation results are in good agreement with the crushing tests, demonstrating the validity of the  DDA method for solving particle crushing problems. Although the improved DDA model is applicable  to rock-fill particle crushing studies, some issues remain, particularly in increasing calculation  efficiency and performing large-scale computations and long real-time simulations. Future research  should address these issues.  Originality/value – A bond model with a revised open-close iteration algorithm is incorporated into  the DDA method. The simulated results shed insight into rock-fill crushing mechanisms, an element of  concern in engineering practices.

点击下载论文

 
多尺度工程地质力学与灾害仿真 研究组  版权所有