A friction stabilizer for supporting a rock ceiling in an underground mining environment is disclosed. The friction stabilizer has an external sheath and an internal rod. The internal rod is about 15% of the length of the external sheath. The internal rod has wedges at either end, arranged to engage with complementary wedges welded to the inside of the sheath.

An end coupling for a rock bolt having a shaft having an external thread, the coupling having an axis and the coupling comprising a body having a leading end and a trailing end spaced apart along the axis, a first passage portion extending along the axis from the leading end; a second passage portion extending along the axis from the trailing end; the first passage portion including a first thread portion to threadingly engage the external thread on the shaft of the rock bolt; the second passage portion including a drive receiving portion arranged to be engaged with a drive inserted into the second passage portion via the trailing end to impart rotation to the coupling about the axis.

A fixation device is described comprising a shaft rotatable about a longitudinal axis with a first cutter at a first, distal end; a guide body on the shaft shaped to taper outwardly towards the first end of the shaft; an elongate sleeve disposed surroundingly about the shaft to be rotatable separately from the shaft and translatable in a longitudinal direction relative to the shaft; a flareable end formation at a first, distal end of the elongate sleeve comprising one or more second cutters; the guide body and flareable end formation being arranged so that urging the sleeve towards the first end over the guide body flares the end formation outward from the shaft; and a tensioning mechanism associated with a second end of the sleeve operable selectively to urge the shaft relative to the sleeve back towards the second end. A method of installing a fixation device into a substrate is also described, for example to serve as an anchor and pile, for example for a submerged or floating object.

A rock bolt to be embedded in a borehole and a method of manufacturing a rock bolt, the rock bolt including an extended energy-absorbing part, the first end of the energy-absorbing part including an anchor and the second end of the energy-absorbing part including a screw joint for prestressing the rock bolt. The rock bolt includes an extended tubular part with a jacket and a first end section and a second end section, with an internal dimension that is larger than the external dimension of the energy-absorbing part and arranged in such a manner that it surrounds the energy-absorbing part.

An encapsulation system for use in securing a rock bolt in a bore hole drilled into a rock face to be stabilised, the encapsulation system comprising at least two separate encapsulation mediums and one or more elongate cartridges containing the encapsulation mediums, each the cartridge having a frangible casing, the encapsulation mediums including: a first encapsulation medium comprising a curable first resin formulation; and a second encapsulation medium; wherein, following use in securing a rock bolt, the second encapsulation medium has a lower bond strength and/or a lower compressive strength than the first resin formulation.

The present invention discloses a self-anchored opposite-pulling anti-impact anchor cable for sectional coal pillars and a using method thereof. The anchor cable includes a steel strand (100), with an energy-absorbing and yielding terminal (200) and a stressed expansion-cracking terminal (300) respectively fixed to two ends of the steel strand, a bushing (400) sleeved outside the steel strand, a first lock (610) provided at one end of the steel strand and a second lock (620) provided at the other end of the steel strand; the stressed expansion-cracking terminal includes a self-anchored bushing (420) with a plurality of pre-splitting lines (440) arranged in the wall of the self-anchored bushing. Under stress, the wall of the self-anchored bushing cracks along the pre-splitting lines and bends and expands, so that it abuts against and is self-anchored to the edge of a sectional coal pillar at the outer side.

A mining bolt system to anchor mining roofs. A bearing plate has a top bearing surface, a bottom bearing surface and a central hole. An L-shaped angle bracket having an upstanding portion and an upper portion has further defined therein a pair of bracket holes. A bolt including a rod portion and a bolt head passes through the central hole and into a mine roof. A threaded staff is then adapted to pass through one of the bracket holes underneath the bottom bearing surface, wherein, in combination, the bearing plate, angle bracket and threaded staff can be tensioned to provide a lifting force against the mine roof.

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, e.g., 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 to engage an abutment or shoulder on the outer or external periphery of the anchor rod to prevent its 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.

The present invention discloses a type of energy-absorbing rock bolt device with umbrella-shaped structure, which consists of a body of bolt, and one end of the said body of bolt is equipped with a preloaded system, as well as the other end of the said body of bolt is equipped with the first support system, in addition, the said body of bolt is equipped with several second support systems, and the said second support system is located between the said preloaded system and the said first support system; meanwhile, the said second support system consists of the first umbrella-shaped support system and the second umbrella support system.

A rock bolt (10) to be received in a drilled hole comprising a threaded shaft (12) and a sleeve (14) into which the shaft (12) is received. A plurality of openings (38) are provided along the length of the sleeve (14) and clamping assemblies (16) each having clamp members (36) are provided adjacent each opening (38). Wedge members (26) are located adjacent each of the clamp members (36) and the wedge members (26) each include a threaded bore for receiving the shaft (12) such that rotation of the shaft (12) moves the wedge members (26) into engagement with the clamp members (36) to move the clamp members (36) outwardly through the openings (38) to engage with an inner surface of the hole.