Patent ID: 9534495
Date: 2017-01-03
CPC Classifications: E21D

Claim:
1. An underground rock anchoring system comprising: a rectilinear blind bore formed within a hanging wall formation; a resin grout pack disposed internally within said blind bore formed within said hanging wall formation; a rock bolt comprising a bolt shaft disposed within said rectilinear blind bore formed within said hanging wall formation such that a distal end portion of said bolt shaft protrudes outwardly from said blind bore, said bolt shaft comprising a hollow cylinder defining a hollow tubular portion extending along the length of said bolt shaft; said bolt shaft comprising multiple sections connected together by an externally threaded male member integrally formed upon a first end of a first one of said multiple sections of said bolt shaft and an internally threaded female member integrally formed upon a first end of a second one of said multiple sections of said bolt shaft which is adapted to be threadedly connected to said first one of said multiple sections of said bolt shaft such that said bolt shaft comprises said multiple sections connected together in order to provide said bolt shaft with a longitudinal extent which is sufficient enough to engage said resin grout pack disposed internally within said blind bore; a bearing plate adapted to be fitted over said protruding end portion of said bolt shaft for bearing against a rock surface portion of said hanging wall formation; and fastening means for moving said bearing plate taut against said rock surface portion of said hanging wall formation; said bolt shaft comprising a proximal end disposed within said blind bore wherein said proximal end of said bolt shaft has a chamfered edge terminating in a pointed tip for piercing said resin grout pack disposed within said blind bore of said hanging wall formation such that when said bolt shaft is sufficiently disposed within said blind bore, said pointed tip of said proximal end of said bolt shaft will pierce said resin grout pack so as to permit said resin grout to be displaced around said proximal end of said bolt shaft disposed within said blind bore and downwardly between annular portions defined between substantially the entire length of said bolt shaft, comprising said multiple sections connected together, and interior wall portions defining said blind bore within said hanging wall formation so as to thereby fixedly secure said bolt shaft within said blind bore when said resin solidifies as a result of rotation of said bolt shaft.