The present invention relates to a support method of preset internal cable for in-situ tunnel expansion project, comprising a cable, lockset and an anchoring agent, wherein before the excavation of the newly-built tunnel, a borehole is drilled into the surrounding rock from the in-situ tunnel, and the cable is installed in the borehole and pre-stressed, so as to play a supporting role at the moment of excavation of the newly-built tunnel. The cable is fixed in the depth of the surrounding rock by the anchoring agent, and the lockset of the cable is set at the position of the excavation contour line of the newly-built tunnel inside the surrounding rock. The present invention provides a method that does not interfere with the excavation construction and can effectively support the surrounding rock of the expanded tunnel in advance. It breaks through the excavation first and then supports model in the previous tunnel construction, and uses the space of the in-situ tunnel for pre-support, and by applying prestress, the deformation of surrounding rock can be controlled to the maximum extent.

A rock anchor assembly includes a rock anchor with a flexible element and first/second cylindrical connector elements engaged to proximal and distal ends of the element, a flexible tubular sleeve longitudinally extending between first and second ends, on the rock anchor so end parts of the rock anchor project from sleeve ends; a load bearing barrel centrally bored engaging the first connector element between the first end of the sleeve and a proximal end of the rock anchor, the barrel engaging the first end of the sleeve in sealing contact, the barrel having a grout conduit between the barrel exterior and the bore, the conduit defining part of a grout passage interconnecting the barrel exterior and sleeve interior, when the barrel engages the sleeve; a seal preventing grout outflow but accommodating grout inflow; a tensioner engaging the first tubular connector element, and a mechanical anchor engaging the second tubular connector.

A friction bolt assembly to frictionally engage a bore formed in rock strata. The assembly includes an elongate tube and an expander mechanism acted on by an anchor mechanism via an elongate bar or cable. A retainer mechanism is mounted to act between the bar or cable and the tube to prevent ejection of the bar or cable from the assembly should the bar or cable break.

A high-strength confined concrete support system for an underground tunnel. The support system includes multiple confined concrete arches, bolts and cables, and a prestressed steel strand backfilling system. The confined concrete arches all support the surrounding rock of the tunnel and are sequentially arranged along the tunnel. Every two adjacent confined concrete arches are connected by a longitudinal connection structure. The support system is provided with a plurality of layers of steel bar meshes on the surrounding rock side and the tunnel side, and shotcrete layers are sprayed on the support system and the steel bar meshes. The prestressed steel strand backfilling system comprises a prestressed steel strand system and a filling material. The filling material fills the space between each confined concrete arch and the surrounding rock to equalize a load on the confined concrete arch and generate prestress.

A friction bolt assembly to frictionally engage a bore formed in rock strata includes an elongate tube and an expander mechanism acted on by an anchor mechanism via an elongate bar or cable. A retainer mechanism is mounted to act between the bar or cable and the tube to prevent ejection of the bar or cable from the assembly should the bar or cable break.

A drilling and bolting tool includes a drill feed for driving a bit to form a hole in a rock surface, a cable feed system, and a resin system. The drill feed includes a frame and a drill head supported on the frame. The cable feed system is coupled to the drill feed, and the cable feed system includes a cable drive for driving a cable into the hole. The resin system includes a hose in fluid communication with a resin supply. The resin system further including a hose drive system for selectively extending the hose into the hole and retracting the hose from the hole.

A carbon fiber rock bolt including: an outer carbon fiber rope including a series of tow fibers; and an inner core material. As the tension on the rock bolt increases beyond a predetermined limit, the inner core material undergoes a spatial compression, whilst the angle of twist in the carbon fiber rope strands decreases, resulting in extension of the carbon fiber rock bolt, replicating the ductility seen in steel rock bolts.

A rock bolt assembly includes a rock bolt with an elongate body between distal and proximal ends, a tubular sleeve with first and second ends, proximal and distal ends of the bolt projecting from first and second ends of the sleeve, a load bearing barrel centrally bored to engage the rock bolt between the sleeve's first end and the bolt's proximal end, which barrel is adapted at a forward end to engage with the sleeve's second end in sealing contact, and which barrel has at least one grout conduit between the barrel's exterior surface and the bore, which at least one conduit defines a part of a grout passage which communicates the exterior surface of the barrel with an interior of the sleeve, when the barrel is engaged with the sleeve, and a seal which seals the grout passage to grout outflow but accommodates inflow of grout from a source.

The present application relates to a system for supporting a roof of a portion of a mine. The system includes a first plurality of stabilizing members disposed above the roof at a first elevation. The first plurality of stabilizing members originate from a first common location and terminate at a second elevation that is higher than the first elevation. The system further includes a second plurality of stabilizing members disposed above the roof and the first plurality of stabilizing members at a third elevation. The second plurality of stabilizing members originate from a second common location and terminate at a fourth elevation that is higher than the third elevation. The second plurality of stabilizing members are disposed generally perpendicular to the first plurality of stabilizing members.

A rock anchor assembly includes a rock anchor with a flexible element and first/second cylindrical connector elements engaged to proximal and distal ends of the element, a flexible tubular sleeve longitudinally extending between first and second ends, on the rock anchor so end parts of the rock anchor project from sleeve ends; a load bearing barrel centrally bored engaging the first connector element between the first end of the sleeve and a proximal end of the rock anchor, the barrel engaging the first end of the sleeve in sealing contact, the barrel having a grout conduit between the barrel exterior and the bore, the conduit defining part of a grout passage interconnecting the barrel exterior and sleeve interior, when the barrel engages the sleeve; a seal preventing grout outflow but accommodating grout inflow; a tensioner engaging the first tubular connector element, and a mechanical anchor engaging the second tubular connector.