Double-wedge rock bolt

A rock bolt comprising:

• a central rod;
• a tubular outer body provided around the central rod along at least a portion of a length of the central rod, and;
• an expansion mechanism arranged for radially expanding the tubular outer body, wherein the expansion mechanism comprises;
• a first wedge means attached to the central rod;
• and
• a second wedge means attached to the outer body between the first wedge means and a trailing portion of the outer body, wherein the first wedge means and the second wedge means are configured such that the first wedge means is arranged to force the second wedge means radially outwards about a longitudinal axis of the rock bolt upon movement of the first wedge means in a first direction towards a trailing portion of the rock bolt to thereby radially expand the outer body, wherein the first wedge means includes a drive wedge attached to the central rod and an intermediate wedge provided around at least a portion of the drive wedge, between the drive wedge and the second wedge means, wherein the drive wedge and the intermediate wedge are configured such that the drive wedge is arranged to radially expand the intermediate wedge upon movement of the drive wedge in the first direction towards a trailing portion of the rock bolt, wherein first wedge means is thus arranged to force the second wedge means radially outwards with the radially expanded intermediate wedge.