Estimation of Fragmentation on Geometrical Viewpoint

Document Type : Research Article

Authors

Dept. of Mining, Petroleum and Geophysics, Shahrood University

10.17383/S2251-6565(15)940915-X

Abstract

Good estimation of fragmentation potential is very important topic before selection of caving extraction methods. In-situ fragmentation is result of discontinuities with zero tension strength but primary and secondary fragmentations happen in rock blocks that seem intact and without any discontinuity. In reality in these blocks when induced stresses (due to under cutting) or shock and stress (due to transition of rock mass) affect the blocks, weak surfaces such as rock bridges, veinlet and schistose surfaces (surfaces with tension strength) are first candidates for breakage and slice. Thus it is necessary to quantify these discontinuities in a rock mass. The purpose is to construct a way for prediction of potential discontinuities. In the next step based on necessary energy for breakage, potential discontinuities are classified. We try to design and construct a new method for quantifying and classifying discontinuities in rock mass.  This method helps us to have an initial estimate of fragmentation when induced stress and large scale displacement affect rock blocks. Rock bridges, veinlet and weak surfaces in rock like as schistose surfaces (surfaces with tension strength) are potential discontinuity. Those joints that have potential of being counted as discontinuities but are not considered discontinuity in in-situ form are put in class No,2 versus in situ fractures (surfaces without tension strength) are classified No,1. fractures which are created after large scale displacements are known class No, 3.

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References

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History

  • Receive Date: 09 February 2015
  • Revise Date: 28 October 2015
  • Accept Date: 28 October 2015

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