Page 456 - Rock Mechanics For Underground Mining
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LONGWALL AND CAVING MINING METHODS





















































              Figure 15.6  Hydraulic prop reac-
              tion to a rockburst: (a) loose rock ac-
              celeratestoavelocity,v;(b)looserock
              continues to move down and is decel-
              erated as kinetic energy is absorbed by
              the work done on the support; (c) loose
              rock comes to rest at a displacement,
              h (after Roberts and Brummer, 1988).


                                        envelope induced by the support element in the hangingwall rock mass intersects the
                                        bedding plane that defines the upper limit of the mass of rock to be supported. The
                                        stress distribution and its lateral extent may be calculated analytically or by using
                                        numerical codes such as UDEC and FLAC. The site-specific design methodology
                                        proposed by Daehnke et al. (2001) consists of two stages – a tributary area analysis
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