A modified solution to assess the required strength of exposed backfill in mine stopes

Backfilling contributes to the improvement of ground stability and reduction of ore dilution in underground mines. A critical issue for backfilled stope design is the required strength for the fill material. A practical solution to address this question was proposed by Mitchell and co-workers for stopes with an exposed face and a high aspect ratio (height H over width B). However, this solution is not directly applicable to stopes with a relatively low aspect ratio (H/B). Its applica- tion is also restricted by additional limitations on the strength along the fill-rock interfaces and the load applied on top of the backfill. In this note, the model proposed by Mitchell and co-workers is modified to provide an estimate of the required strength of backfill for various geometries, material properties, and surface loads. The modified Mitchell (MM) solution is validated against experimental results. Sample calculations with the MM solution are also presented and discussed.

[1]  LiLi,et al.  Effect of drainage and sequential filling on the behavior of backfill in mine stopes , 2014 .

[2]  B. Muhunthan,et al.  Effect of cement treatment on geotechnical properties of some Washington State soils , 2009 .

[3]  P. T. W. Lun.  Soil reinforcing technique in mine backfilling , 1986 .

[4]  E. De Souza,et al.  Engineering Design of Backfill Systems in Adjacent Pillar Mining , 2008 .

[5]  Hans Vaziri,et al.  Use of A¯=0 as a Failure Criterion for Weakly Cemented Soils , 2011 .

[6]  Kandiah Pirapakaran.  Load-deformation characteristics of minefills with particular reference to arching and stress developments , 2008 .

[7]  Steve Zou,et al.  Optimizing backfill design for ground support and cost saving , 2006 .

[8]  Mostafa Benzaazoua,et al.  Design and Application of Underground Mine Paste Backfill Technology , 2008 .

[9]  Li Li,et al.  A new concept of backfill design—Application of wick drains in backfilled stopes , 2013 .

[10]  David F. McCarthy,et al.  Essentials of Soil Mechanics and Foundations: Basic Geotechnics , 1982 .

[11]  R. Pakalnis,et al.  Composite paste barricade performance at Goldcorp Inc. Red Lake Mine, Ontario, Canada , 2010 .

[12]  Hans Vaziri,et al.  Strength of Weakly Cemented Sands from Drained Multistage Triaxial Tests , 2011 .

[13]  Marco Barla,et al.  Microparameters Calibration for Loose and Cemented Soil When Using Particle Methods , 2009 .

[14]  Michel Aubertin,et al.  Numerical Investigation of the Stress State in Inclined Backfilled Stopes , 2009 .

[15]  Kent Robertson Van Horn,et al.  Design and application , 1967 .

[16]  Michel Aubertin,et al.  A Three-Dimensional Analysis of the Total and Effective Stresses in Submerged Backfilled Stopes , 2009 .

[17]  Yves Potvin,et al.  Backfill at Sons of Gwalia Mine , 2004 .

[18]  JamesMichael,et al.  A laboratory investigation of the dynamic properties of tailings , 2011 .

[19]  Li Li,et al.  Formulation of a three dimensional analytical solution to evaluate stresses in backfilled vertical narrow openings , 2005 .

[20]  Othman Nasir,et al.  Mechanical Behaviour of the Interface Between Cemented Tailings Backfill and Retaining Structures Under Shear Loads , 2010 .

[21]  Robert J. Mitchell,et al.  Model studies on cemented tailings used in mine backfill , 1982 .