Abstract: Disclosed is a rock bolt assembly including: an elongate bolt extending with distal and proximal ends; a tubular sleeve longitudinally extending between leading and trailing ends on the bolt so at least a proximal end portion projects from the trailing end of the sleeve; and a nozzle docking bush on the proximal end portion between the sleeve's trailing end and the bolt's proximal end. The bush has a cylindrical body between first and second ends, a central hole extending through the body, spaced-apart annular ridges on the cylindrical body, a grout distributing channel between the ridges, and an aperture in the channel connecting the channel and hole. The central hole includes a leading portion ending at the first end, sealingly receiving the trailing end. A trailing portion of the central hole ends at the second end and sealingly engages the bolt. Each annular ridge seals against a grout nozzle.

Abstract: A single-use sealing bush which is adapted to form a sealing interface between a rock bolt and a nozzle of a grout delivery system, the sealing bush including a cylindrical body defined between a first end and a second end; a hole in the first end of the body that is adapted to receive the rock bolt; a pair of spaced apart annular ridges, on an outer cylindrical surface of the body, between which a grout distributing channel is defined; and an aperture which connects the channel to the recess; wherein each annular ridge is adapted to seal against the nozzle in a position which communicates a grout inlet port of the nozzle with the grout distributing channel.

Abstract: Disclosed is a rock bolt assembly including: a rock bolt with an elongate body which extends between a distal end and a proximal end and which has an integrally formed anchor portion and, where the body is not so formed, cylindrical stem portions; a tubular sleeve with a first diameter, which longitudinally extends between a first end and a second end, partially encasing the rock bolt so at least a proximal end portion of the bolt projects from the first end of the sleeve; a grout-input element which engages the rock bolt on the proximal end portion and which engages the first end of the sleeve in sealing contact; wherein, over each stem portion, the tubular sleeve is adapted along a band section by a reduction in the first diameter in a diametric plane; and wherein, over the anchor portion, the tubular sleeve retains the first diameter.

Abstract: Disclosed is a self-drilling resin anchored rock bolt with an elongate body of a suitable metal material extending between distal and proximal ends; and a drill bit engaged to the distal end; which body includes a threaded portion at the proximal end, a resin bore which extends through the elongate body, opening at each of the ends, a first integral anchor on the body, including integrally formed paddle formations; wherein the drill bit engaged with the body has a resin conduit which communicates an exterior of the drill bit with the resin bore; wherein the threaded portion has a first section, with a first thread density, extending from the proximal end, and a second section, with a second thread density, starting at the end of the first section and extending towards the distal end; and wherein the first thread density is lower than the second thread density.

Abstract: The various disclosed embodiments provide a split set type composite rockbolt which has a slot extending from a chamfered tip of a tubular body portion of the rockbolt and through a neck portion partway to a collar portion. The rockbolt is made of a composite material which has a resin medium with longitudinal and circumferential fibres.

Abstract: Disclosed is a method of adapting a metal bar, for use as a rock bolt, to ensure that the bar will break in a predictable manner, the method including the step of removing material from the bar in a circumferential band to reduce a diameter of the bar within the band to a minor diameter thereby to provide a failure zone within which the bar will break if subjected to enough tensile load.

Abstract: A single-use sealing bush which is adapted to form a sealing interface between a rock bolt and a nozzle of a grout delivery system, the sealing bush including a cylindrical body defined between a first end and a second end; a hole in the first end of the body that is adapted to receive the rock bolt; a pair of spaced apart annular ridges, on an outer cylindrical surface of the body, between which a grout distributing channel is defined; and an aperture which connects the channel to the recess; wherein each annular ridge is adapted to seal against the nozzle in a position which communicates a grout inlet port of the nozzle with the grout distributing channel.

Abstract: Disclosed is a rock bolt assembly including: an elongate bolt extending with distal and proximal ends; a tubular sleeve longitudinally extending between leading and trailing ends on the bolt so at least a proximal end portion projects from the trailing end of the sleeve; and a nozzle docking bush on the proximal end portion between the sleeve's trailing end and the bolt's proximal end. The bush has a cylindrical body between first and second ends, a central hole extending through the body, spaced-apart annular ridges on the cylindrical body, a grout distributing channel between the ridges, and an aperture in the channel connecting the channel and hole. The central hole includes a leading portion ending at the first end, sealingly receiving the trailing end. A trailing portion of the central hole ends at the second end and sealingly engages the bolt. Each annular ridge seals against a grout nozzle.

Abstract: The various disclosed embodiments provide a split set type composite rockbolt which has a slot extending from a chamfered tip of a tubular body portion of the rockbolt and through a neck portion partway to a collar portion. The rockbolt is made of a composite material which has a resin medium with longitudinal and circumferential fibres.

Abstract: Disclosed is a method of adapting a metal bar, for use as a rock bolt, to ensure that the bar will break in a predictable manner, the method including the step of removing material from the bar in a circumferential band to reduce a diameter of the bar within the band to a minor diameter thereby to provide a failure zone within which the bar will break if subjected to enough tensile load.

Abstract: 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.

Abstract: 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.

Abstract: Disclosed is a rock bolt installation tool for installation of a rock bolt assembly into a predrilled rock hole. The tool includes a drive shaft having a proximal end, which is adapted to engage with a drill rig, and a distal end. A socket in the distal end includes a first containment portion, of a first diameter, which has a base and a second containment portion, of a second diameter, between the first containment portion and the second end. The first containment portion is adapted to receive a nut of the rock bolt assembly. The second containment portion is adapted to receive a load-indicator of the rock bolt assembly. The base and the second end are adapted to provide surfaces against which the nut and a spherical seat of the rock bolt assembly respectively engage to be driven into the rock hole.

Abstract: 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.

Abstract: 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.

Abstract: Disclosed is a cable anchor assembly including: a cable anchor body longitudinally extending between leading and trailing ends; a tensioning device with an outer member having first and second ends and a threaded through passage between the ends and an inner member which threadedly engages the threaded passage of the outer member and fixedly attached to the cable anchor body at or towards the trailing end; a faceplate engaging the cable anchor body between the leading end and the tensioning device. In use, with the cable anchor body inserted in a borehole and anchored therein, the faceplate positioned against a rock face and the first end of the outer member abutting the faceplate, the outer member is rotatable relative to the inner member, causing the inner member to move within the passage towards the second end of the outer member, drawing on the cable anchor body, tensioning the body.

Abstract: A hanging wall movement detection apparatus includes a rigid elongate member which extends between a first end and a second end, an indicator module which produces a warning signal when actuated, axially movably engaged with the elongate member, a ground engaging support which rigidly supports the indicator module off the ground, an actuator engaged with the elongate member between the first end and the indicator module, a biasing separator between the actuator and the indicator module. The actuator is drawn towards the indicator module, compressing the biasing separator, when the elongate member experiences a pulling force at the second end in an axial direction away from the indicator module, and the actuator contacts the indicator module to actuate the module to produce a warning signal if the pulling force is of a sufficient magnitude to overcome the bias of the biasing separator.

Abstract: Disclosed is a cable anchor assembly including: a cable anchor body longitudinally extending between leading and trailing ends; a tensioning device with an outer member having first and second ends and a threaded through passage between the ends and an inner member which threadedly engages the threaded passage of the outer member and fixedly attached to the cable anchor body at or towards the trailing end; a faceplate engaging the cable anchor body between the leading end and the tensioning device. In use, with the cable anchor body inserted in a borehole and anchored therein, the faceplate positioned against a rock face and the first end of the outer member abutting the faceplate, the outer member is rotatable relative to the inner member, causing the inner member to move within the passage towards the second end of the outer member, drawing on the cable anchor body, tensioning the body.

Abstract: The invention provides a rock wall closure detection apparatus which includes an elongate member, variably extensible between a first wall and a second wall Of an underground excavation which comprises of a first and a second segment which are resiliently axially compressible relatively to one another when the waits close and an indicator module which produces a warning signal when actuated, attached to the first segment and an actuator attached to the second segment wherein on compression of the member, the actuator moves relatively to the module to actuate the module to produce the warning signal.

Abstract: A hanging wall movement detection apparatus includes a rigid elongate member which extends between a first end and a second end, an indicator module which produces a warning signal when actuated, axially movably engaged with the elongate member, a ground engaging support which rigidly supports the indicator module off the ground, an actuator engaged with the elongate member between the first end and the indicator module, a biasing separator between the actuator and the indicator module. The actuator is drawn towards the indicator module, compressing the biasing separator, when the elongate member experiences a pulling force at the second end in an axial direction away from the indicator module, and the actuator contacts the indicator module to actuate the module to produce a warning signal if the pulling force is of a sufficient magnitude to overcome the bias of the biasing separator.