The invention relates to a sleeveless energy absorbing rock bolt. A first end of the rock bolt is configured to facilitate the mixing of an anchoring composition and/or anchoring the rock bolt in the rock. The rock bolt comprises manganese alloyed steel, and exhibits, post the yield point thereof, under static load conditions, an increase in load capacity and an increasing displacement until the break or fail point of the rock bolt is reached.

The present disclosure provides a system to optimally set an anchor and a bullet within a bore hole. The anchor is comprised of at least two cutters connected to and positioned below spreading lamellae of the anchor. The cutters are comprised of a wide edge and a narrow edge, the wide edge having a width that is wider than the circumference of the spreading lamellae to facilitate the setting of the anchor. A space is also initially provided between each of the cutters and the bullet to reduce friction of anchor on the bullet during expansion. During setting, the spreading lamellae of the anchor spread radially over the bullet to set the undercut anchor within the pre-drilled bore hole. In another embodiment, the anchor is comprised of at least two angular cutters having a taper of several degrees to facilitate cutting through the cementitious material of the bore hole.

The invention relates to a sleeveless energy absorbing rock bolt. A first end of the rock bolt is configured to facilitate the mixing of an anchoring composition and/or anchoring the rock bolt in the rock. The rock bolt comprises manganese alloyed steel, and exhibits, post the yield point thereof, under static load conditions, an increase in load capacity and an increasing displacement until the break or fail point of the rock bolt is reached.

The present invention provides a retainer device 1 for retaining or holding an anchor rod 11 of a rock anchor, especially a self-drilling anchor, in a hole H drilled above horizontal. The retainer device 1 comprises: a body portion 2 configured to be mounted on the anchor rod 11, and especially on an outer or external periphery of the anchor rod, and at least one locking arm or tab 6, 7 that projects from the body portion 2 in a direction transverse to a longitudinal extent of the anchor rod 11. The body portion 2 is configured for movement relative to the anchor rod 11 in use, and the at least one arm or tab 6, 7 is configured to deform so as to engage and bear against an inner wall W of the hole H when the retainer device 1 mounted on the anchor rod 11 is driven into the hole H. The invention also relates to a rock anchor system 10, comprising: at least one elongate anchor rod 11; a drill bit 12 configured for attachment to one end region 13 of the elongate anchor rod 11 for drilling the anchor rod 11 into rock strata R; and at least one retainer device 1 according to the invention described above for retaining or holding the anchor rod 11 in a hole H drilled in the rock strata R above horizontal. The invention also provides a method for installing a rock anchor.

A method and an apparatus for rock reinforcement are described. The method comprises the steps: to inject a first component and a second component through a first channel and a second channel respectively into a rock hole, wherein the first component and the second component are adapted for rock reinforcement and to inject a blocking agent through a third channel into at least said second channel, wherein said blocking agent provides a barrier in at least said second channel.

The present invention provides a self-drilling and self-anchoring extendable anchor rod applicable to soft and weak coal rocks and an anchoring method thereof, which are suitable for supporting soft and weak coal rock mass in roadways.

A drilling assembly is disclosed for drilling a borehole in a rock body and inserting a rock bolt within the borehole in a single pass. The drilling assembly includes an elongated drill string having a downhole end. A drill bit is detachably joined to the downhole end of the drill string, with the drill bit having an external screw thread extending in an axial direction of the drill string. The drill string is surrounded by a rock bolt sleeve that has a thread engaging formation at or near its downhole end and that is arranged to cooperate with the external screw thread of the drill bit so that the drill bit is able to be screwed into the rock bolt sleeve.

The present invention provides a self-drilling and self-anchoring extendable anchor rod applicable to soft and weak coal rocks and an anchoring method thereof, which are suitable for supporting soft and weak coal rock mass in roadways.

An injection system for a self-drilling rock bolt assembly (1), the system including: a receptacle (2) to be fixed in use to a drill head (4) of the self-drilling rock bolt assembly (1), the receptacle (2) having a nozzle receiving end (5) and an opening (6) at the other: a replaceable canister (7) to be located within said receptacle (2) in use, said canister (7) adapted to supply two or more substances for use in installing the rock bolt assembly (1) through said nozzle receiving end (5); and a plunger system (8) operatively associated with said receptacle (2) adjacent said opening (6) at said other end and positioned along a longitudinal axis (XX) of the drill head (4): the plunger system (8) including two or more plungers (9) that are activated in use to drive the substances within the canister (7) when located within the receptacle (2), delivering the substances by way of a nozzle (21) mounted to the nozzle receiving end (5) into the self-drilling rock bolt assembly (1).

The present application relates to a system for supporting a roof of a portion of a mine. The system includes a first plurality of stabilizing members disposed above the roof at a first elevation. The first plurality of stabilizing members originate from a first common location and terminate at a second elevation that is higher than the first elevation. The system further includes a second plurality of stabilizing members disposed above the roof and the first plurality of stabilizing members at a third elevation. The second plurality of stabilizing members originate from a second common location and terminate at a fourth elevation that is higher than the third elevation. The second plurality of stabilizing members are disposed generally perpendicular to the first plurality of stabilizing members.