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.

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.

A grouting device for high-coagulability grouting materialsincludes a grouting pipe, a connector and a self-sealing pipe head, wherein one end of the connector is connected with a grouting pump through the grouting pipe, the other end of the connector is connected with the self-sealing pipe head through the grouting pipe, and the grouting pipe is connected with the connector and the self-sealing pipe head in a fixed and sealed mode. The grouting device is easy to install, features reliable connection between the grouting pipe and the connector and the self-sealing pipe head, and can be reused. Because the inner diameter of the connector is consistent with the inner diameter of the grouting pipe, and a slurry outlet on an end cap of the self-sealing pipe head is a circular slurry outlet, pressure loss in the grouting process is effectively reduced, and the grouting effect is good.

A pumpable resin system for installation of mine roof bolts includes a resin feed pump in fluid communication with a resin source, a catalyst feed pump in fluid communication with a catalyst source, a resin injection cylinder pump in fluid communication with the resin feed pump, with the resin feed pump configured to transfer resin to the resin injection cylinder pump when the resin feed pump is actuated, a catalyst injection cylinder pump in fluid communication with the catalyst feed pump, the catalyst feed pump configured to transfer catalyst to the catalyst injection cylinder pump when the catalyst feed pump is actuated, a hydraulic piston, with the resin injection cylinder pump and the catalyst injection cylinder pump slaved together and controlled by the hydraulic piston, a resin line in fluid communication with the resin injection cylinder pump, and a catalyst line in fluid communication with the catalyst injection cylinder pump.

An inorganic mortar system for chemical fastening of an anchor in mineral substrates can contain at least one hard aggregate having a Mohs-hardness of greater than or equal to 8. The inorganic mortar system contains a curable aluminous cement component A and an initiator component B for initiating the curing process. Component A contains at least one blocking agent selected from boric acid, phosphoric acid, metaphosphoric acid, phosphorous acid, phosphoric acid, and salts and mixtures thereof. Component B contains an initiator, at least one retarder, at least one mineral filler, and water. The use of at least one hard aggregate having a Mohs-hardness of greater than or equal to 8 in an inorganic mortar increases load values and reduces shrinkage. A method can be used for chemical fastening of an anchor, preferably of metal elements, in mineral substrates, such as structures made of brickwork, concrete, pervious concrete, or natural stone.

Disclosed are a method and system for temporary coating supporting and permanent bolt supporting. Tunnel excavation construction operation is composed of a plurality of operation cycle units, and each of the operation cycle units includes: excavating by at least one row pitch to form a new tunnel; spraying a coating material onto a surface of the new tunnel to form a sealing coat on a surface of surrounding rock, wherein the sealing coat has an adhesive property and a sealing property both meeting preset conditions, and has a tensile strength and a toughness needed for supporting; and inserting bolts into the new tunnel to perform permanent supporting.

Disclosed are a method and system for temporary coating supporting and permanent bolt supporting. Tunnel excavation construction operation is composed of a plurality of operation cycle units, and each of the operation cycle units includes: excavating by at least one row pitch to form a new tunnel; spraying a coating material onto a surface of the new tunnel to form a sealing coat on a surface of surrounding rock, wherein the sealing coat has an adhesive property and a sealing property both meeting preset conditions, and has a tensile strength and a toughness needed for supporting; and inserting bolts into the new tunnel to perform permanent supporting.

A pumpable resin system for installation of mine bolts includes a resin injection cylinder comprising a resin chamber and a resin hydraulic cylinder, a catalyst injection cylinder including a catalyst chamber and a catalyst hydraulic cylinder, with the resin hydraulic cylinder synchronized with the catalyst hydraulic cylinder, a hydraulic pump in fluid communication with the resin hydraulic cylinder and the catalyst hydraulic cylinder, a hydraulic reservoir in fluid communication with the hydraulic pump, and a delivery line in fluid communication with the resin injection cylinder and the catalyst injection cylinder. The delivery line is configured to deliver resin and catalyst from the resin injection cylinder and catalyst injection cylinder into a borehole.

The present disclosure relates to a technical field of coal mining, in particular to a surrounding rock stability control method adapted for a coal mining area main roadway. The method comprises the following steps: reinforcing support on a roof and two sides of the mining area main roadway on a basis of an original support form; digging a safety roadway along a stop line of a present working face required by coal mine design, and supporting the safety roadway, wherein a protective coal pillar is formed between the safety roadway and the mining area main roadway; performing slitting blasting on the roof in the safety roadway, wherein blast holes are arranged on a roadway corner line on one side of the present working face to form a pre-splitting slit; and performing stoping at a next working face after completing coal mining at the present working face when stoping at the present working face advances to the safety roadway. By cutting the roof and relieving pressure at the stop mining line of the working face, an influence of mining disturbance on stability of the mining area main roadway in the stoping process of the working face is reduced, and by reinforcing support, a yielding deformation capacity of the mining area main roadway is improved, and the stability of the surrounding rock of the mining area main roadway is further improved.

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.