A cable bolt assembly is disclosed comprising a cable bolt having a shaft, an end fitting disposed on the shaft and including an end fitting body. Mechanical interlocking is provided between the body and the shaft to form a connection therebetween. The mechanical interlocking may be formed directly between the body and the shaft and/or by engagement formations disposed intermediate the body and shaft. The body further including an exterior profiling arranged to engage a further component of the end fitting to install and/or tension the cable bolt assembly in use. A method of forming the cable bolt assembly is also disclosed.

Provided is a mounting method for an extensible reaming self-anchoring anchor rod, which is especially applicable to roadway construction in coal mines. A big helical structure is arranged on two rod sections of a sectional type anchor rod, a simple drill bit drills and reams a bore and cuts the coal mass in one operation, the outer diameter of the simple drill bit is smaller than the outer diameter of the big helical rod body, and the big helical structure accomplishes secondary reaming, self-drilling and self-anchoring in the drilling process; the big helical structure inhibits propagation and development of sheet cracks of the coal wall in the radial direction, and is embedded in the coal mass through a self-stabilization process of the rock mass.

Provided is a mounting method for an extensible reaming self-anchoring anchor rod, which is especially applicable to roadway construction in coal mines. A big helical structure is arranged on two rod sections of a sectional type anchor rod, a simple drill bit drills and reams a bore and cuts the coal mass in one operation, the outer diameter of the simple drill bit is smaller than the outer diameter of the big helical rod body, and the big helical structure accomplishes secondary reaming, self-drilling and self-anchoring in the drilling process; the big helical structure inhibits propagation and development of sheet cracks of the coal wall in the radial direction, and is embedded in the coal mass through a self-stabilization process of the rock mass.

A system for re-tensioning mine roof channels includes a roof plate having a first side, a second side positioned opposite the first side, and a sidewall extending therebetween, where the first side is configured to engage a surface of a mine roof, and where the sidewall defines a radially extending slot configured to receive a mine roof bolt. The system also includes a spacer having a first side, a second side positioned opposite the first side, and a sidewall extending therebetween, with the first side of the spacer configured to engage with the second side of the roof plate, and the sidewall defining a slot configured to receive a mine roof bolt, and a nut having a first side, a second side positioned opposite the first side, a sidewall therebetween, and a threaded opening, with the sidewall defining a radially extending slot configured to receive a mine roof bolt.

The present invention pertains to a yieldable rock anchor (10), comprising an elongated tendon (12) extending longitudinally along a tendon axis (A) from a proximal end (16) to a distal end (18), wherein the tendon includes a substantially non-yielding rigid first anchor portion (20) at or near said distal end (18) and extending towards said proximal end (16), and at least one plastically deformable axially yielding portion (26) intermediate said non-yielding rigid first anchor portion (20) and said proximal end (16). The first anchor portion (20) may be a hollow bar member, and the first anchor portion (20) and the at least one yielding portion (26) are integrally joined or coupled to one another to form at least part of said elongated tendon (12).

A friction bolt assembly, such as for use with a pneumatically actuated drill, with a friction fit tubular sleeve longitudinally extending between a leading end and a trailing end, a rod which longitudinally extends through the sleeve between a first end and a second end, and which projects from either end of the sleeve to define, between the first end of the rod and the leading end of the sleeve and the second end of the rod and the trailing end of the sleeve respectively, a leading part and a trailing part, an expansion element mounted on or formed with the rod, on the leading part, a drill engaging element axially fixed in position on the second end of the bolt and engageable with a chuck or an end of the rock drill, a first load bearing formation mounted on the trailing part of the rod and which engages the trailing end of the sleeve, and a second load bearing formation mounted over the trailing part of the rod between the first load bearing formation and the drill engaging element.

An energy-absorbing rockbolt includes an anchorage structure, wherein two ends of the anchorage structure are respectively provided with a mixing blade and a threaded fastening section; a nut is screwed to the threaded fastening section; a plate is mounted at one end, which is close to the threaded fastening section, of the anchorage structure in a sleeving manner; one side of the plate abuts against the nut; the anchorage structure consists of first anchorage structure parts and second anchorage structure parts, wherein the second anchorage structure parts are arranged between two first anchorage structure parts; each of the second anchorage structure parts is an elliptical rod-shaped structure; a plurality of inwardly-concave arc-shaped grooves are formed in an outer wall of the second anchorage structure part in an axial direction, and a reinforcing rib is convexly formed at an intersection of two adjacent arc-shaped grooves.

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.

An M-type energy-absorbing rockbolt includes an anchorage structure, wherein two ends of the anchorage structure are respectively provided with a mixing blade and a threaded fastening section; a nut is screwed to the threaded fastening section; a plate is mounted at one end, which is close to the threaded fastening section, of the anchorage structure in a sleeving manner; one side of the plate abuts against the nut; the anchorage structure consists of first anchorage structure parts and second anchorage structure parts, wherein the second anchorage structure parts are arranged between two first anchorage structure parts; each of the second anchorage structure parts adopts an elliptical rod-shaped structure; a plurality of inwardly-concave arc-shaped grooves are formed in an outer wall of the second anchorage structure part in an axial direction, and a reinforcing rib is convexly formed at an intersection of two adjacent arc-shaped grooves.

A friction bolt assembly, such as for use with a pneumatically actuated drill, with a friction fit tubular sleeve longitudinally extending between a leading end and a trailing end, a rod which longitudinally extends through the sleeve between a first end and a second end, and which projects from either end of the sleeve to define, between the first end of the rod and the leading end of the sleeve and the second end of the rod and the trailing end of the sleeve respectively, a leading part and a trailing part, an expansion element mounted on or formed with the rod, on the leading part, a drill engaging element axially fixed in position on the second end of the bolt and engageable with a chuck or an end of the rock drill, a first load bearing formation mounted on the trailing part of the rod and which engages the trailing end of the sleeve, and a second load bearing formation mounted over the trailing part of the rod between the first load bearing formation and the drill engaging element.