Discrete fracture network modeling for estimation of rock mass in-situ fragmentation in caving extraction methods

Document Type : Original Article

Authors

1 . PhD Student of Mining Engineering, Shahrood University of Technology,

2 Associate Prof., Department of Mining Engineering, Shahrood University of Technology

3 Assistant Prof., Department of Mining Enginneering, Yazd University

Abstract

One of the most critical factors for estimation of cavability in prefeasibility stage in caving extraction methods is evaluation of In situ fragmentation. Poor estimation of this variable can lead to production and processing problems, or in the worst scenario, failure of the project. In recent years with help of new stochastic discontinuity geometrical modeling, joints those are the main factor for in situ fragmentation, modeled more in tune with reality. Often in nature, discontinuity persistence especially in joints is not infinite. This has a great impact on the cavability of ore bodies. In a new recent stochastic geometrical modeling that is named discrete fracture network (DFN), discontinuities modeled finite that is more in tune with reality. Mathematica Software is selected for writing 2dimensional discrete fracture network code (DFN2D), because of its good graphics and calculations abilities. This code (DFN2D) has good different abilities like producing of numerical and graphical outputs, making finite and infinite joints models, defining of complete blocks with computation of their areas from joints intersections, consideration of joints hierarchies, production of suitable outputs for numerical codes like UDEC & PFC2D and statistics outputs of any model geometrical parameters. With processing of information from joint study in a copper mine and fitness of well probability density functions for any geometrical parameters of joint sets, 2D geometrical modeling with DFN2D was made. Statistics outputs from model and joint intensity and density had a good fitness with reality (input data). In situ fragmentation computed from area of complete blocks also rate of blocky area is defined.

Keywords

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References

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Scientific Quarterly Journal of Iranian Association of Engineering Geology
Volume 9, Number 1 & 2
September 2016
Pages 27-44

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History

  • Receive Date: 27 June 2014
  • Revise Date: 19 March 2016
  • Accept Date: 28 September 2016

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