A tool to aid in the installation of a rock bolt assembly in a rock hole which includes a drive shaft having a proximal end, which is adapted to engage with a drilling rig, and a distal end which includes a recess which is adapted to receive a trailing end portion of the rock bolt and which has a first seat against which an axially pre-set component of the rock bolt assembly abuts, a tubular sleeve telescopically engaged with the shaft which has a first end, which is adapted to receive an axially moveable component of the rock bolt assembly and which has a second seat against which the axially moveable component abuts, and a second end, wherein the sleeve is reciprocally moveable relatively to the shaft between a biased forward position in which the axially pre-set component and the axially moveable component are spaced, and a retracted second position in which the axially pre-set component engages or connects to the axially moveable component.

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.

A rock anchor assembly includes: a tubular sleeve between first and second ends, having an anchor retaining portion opening on the second end; a rock anchor with an elongate body extending between distal and proximal ends, received in the tubular sleeve with the proximal and distal ends of the body projecting from the first and second ends respectively of the sleeve; a tensioning and locking assemblage on the anchor body between the proximal end and the first end of the sleeve, a forward part being engageable with the first end of the sleeve; and a mechanical anchor engaged to the anchor body at the distal end which, from an unexpanded configuration, expands radially to an expanded configuration. The anchor retaining portion at least partially retains the mechanical anchor in the unexpanded configuration. The anchor retaining portion expands circumferentially to accommodate retracted ingress of the anchor in the expanded configuration.

A rock anchor assembly includes: a resiliently radially deformable tubular member longitudinally extending between leading and trailing ends and which has an arrestor formation integral with, or engaged to, a trailing end part of the member; an elongate element longitudinally extending through the member between first and second ends and which attaches to the tubular member at spaced distal and proximal load points and which has a failure arrestor fixed at a point within the member; and a faceplate on the tubular member or the elongate member. When the assembly is inserted in a rock hole, with the faceplate bearing against the rock face, and load is applied along the elongate element that will cause the element to sever above the point at which the arrestor is fixed, the failure arrestor engages the arrestor formation, arresting the ejectment of a proximal portion of the elongate element from the hole.

It discloses a grouting bolt-cable composite beam and supporting method for advanced support of fractured surrounding rock in deep coal mines. The quadrate plates are fixed at both ends of the steel beam, the anchor cable holes are arranged in the center of the steel beam and the quadrate plates, and the diameter of anchor bolt holes should be larger than that of the grouting cables. There are four anchor bolt holes on each quadrate plate, and each anchor bolt hole corresponds to a anchor plate, the horizontal surface of the anchor plate is close to the quadrate plate, and the arc parts of the four anchor plates are all facing the center of the quadrate plate.

An elongated connecting element for anchoring members, which is provided with a first anchoring end portion designed to be inserted into an anchoring region and a second end portion which defines a head, which lies opposite the first anchoring end portion and is designed to interact with an element to be anchored. The elongated connecting element includes an external tubular element which accommodates an internal elongated body, the external tubular element defining, at the head, at least one feeding port for a synthetic anchoring mix and, at the first anchoring end portion, at least one exit opening for the synthetic anchoring mix. The synthetic anchoring mix is configured to set, penetrating at least partially into the anchoring region and creating a stable connection between the anchoring region and the elongated connecting element and between the respective portions of the external tubular element and of the internal elongated body.

An anchor rod includes a sleeve open at one end and having a blocking plate at the other end; a pressure relief pipe fixedly arranged on an inner wall of the sleeve; and a rod body. A guide hole is formed in a center of the blocking plate. A part of the rod body penetrates through the guide hole and extends into the sleeve. A gap is formed between the pressure relief pipe and the blocking plate. An overflow valve is connected to the pressure relief pipe. A piston in sliding seal fit with the sleeve and the pressure relief pipe is arranged at the rod body. A sealing ring in sliding seal fit with the rod body is arranged at the inner wall of the guide hole; and a sealing cavity between the blocking plate and the piston in the sleeve is filled with emulsion.

An asymmetric coordinated support device for gob side entry is provided. The device includes an inner support board, an outer roadway side support assembly, an outer roof support assembly, and a flexible reinforcement layer, wherein the inner support board is supported to an innermost side closest to a rock layer to be supported in an extending direction of the roadway, and wherein a side of the inner support board remote from the rock layer is provided with the outer roadway side support assembly extending along the roadway direction and the outer roof support assembly located on a roof of the outer roadway side support assembly.

Amorphous calcium carbonate is included in a fire-resistant inorganic mortar system for a fire-resistant chemical fastening of anchors and post-installed reinforcing bars in mineral substrates. The system includes a curable aluminous cement component A and an initiator component B for initiating the curing process. The component A includes at least one blocking agent selected from the group of phosphoric acid, metaphosphoric acid, phosphorous acid and phosphoric acids, at least one plasticizer and water. The component B includes an initiator, at least one retarder, at least one mineral filler and water. Moreover, amorphous calcium carbonate in a fire-resistant inorganic mortar increases load values. Also, a method is used for a fire-resistant chemical fastening of anchors and post-installed reinforcing bars in mineral substrates, such as structures made of brickwork, concrete, pervious concrete or natural stone.

A bolting and drilling system comprising a vehicle, a gantry mounted to the vehicle, a boom assembly having a first end mounted to the gantry and a second end having a first quick connector and a second quick connector. The system includes a bolter assembly connectable to the first quick connector, wherein the bolter assembly comprises a stinger, a drill and a bolter for stinging, drilling and bolting a roof of an underground mine. The system includes a drill feed assembly connectable to the second quick connector, wherein the drill feed assembly comprises a drill for drilling a rock face of a heading. The drill feed assembly is longer than the bolter assembly.