Rock anchors, inflation chucks, and inflation systems such as those described herein, allow for substantially complete draining of fluids from interior volumes of the rock anchors. In various situations, corrosive fluids may be introduced to the rock anchor, including inflating the rock anchors and during normal use, such as by groundwater intrusion. The inflation chucks described herein include multiple inflation paths for more effectively introducing and draining fluid from rock anchors during inflation processes and during general use.

The invention discloses a retrievable sand consolidation anchor head prestressed anchor rod, an anchoring jack and an application method thereof, and belongs to the technical field of geotechnical engineering. The retrievable sand-consolidated anchor head pre-stressed anchor includes a bolt body 6, a rigid frame 5, a load member 1, a sand column 2, a pressure receiving member 4, a cut-off member 3, and an anchor pier 8. The anchoring jack includes a force transmitting frame 12, a first guiding plate 25, a second guiding plate 28, and a housing 13. The application method includes an anchoring method using the retrievable sand-consolidated anchor head prestressed anchor rod and a method of recovering the retrievable sand-consolidated anchor head pre-stressed anchor rod. After the anchoring of the reclaimed sand-consolidated anchor head pre-stressed anchor rod, the bolt body can be recovered and reused, and the operation is simpler and more environmentally friendly.

A friction rock bolt assembly is arranged to frictionally engage an internal surface of a bore formed in rock strata. The rock bolt includes an expander mechanism having at least two radially outer wedge elements engageable by an inner wedge element. The expander mechanism is configured for symmetrical displacement of the expander elements to provide controlled enlargement by the rock bolt within the borehole for secure anchorage.

A friction rock bolt assembly is arranged to frictionally engage an internal surface of the bore formed in rock strata. The rock bolt includes a loading mechanism provided at a rearward end of the rock bolt having a load absorber to absorb an initial predetermined loading force followed by transfer of the force to a main load element.

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.

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.

The present disclosure relates to a construction method for a deformable anchor cable capable of being prestressed. The anchor cable includes an outer sleeve, a shrinkage pipe, an inner sleeve, a steel strand, an anchor and a tray. When the anchor cable is in use, a hole is drilled first, then the anchor cable is mounted in the drilled hole, and finally a prestress is applied to the steel strand of the anchor cable. According to the construction method, the construction is convenient; the anchor cable has the characteristics of high strength and large deformation, and can be easily prestressed; and the large deformation is realized by squeezing the inner sleeve by means of the anchor, which completely overcomes the problem of breaking a cold-drawn rod during the large deformation process.

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 rock bolt (10) is provided for frictionally engaging with the internal surface of a bore drilled into rockmass. The bolt comprises a tube having a circular cross-section (12) defining a longitudinal split (14) and a longitudinal axis (10a). The tube (12) in is radially expandable. The bolt (10) has a first leading end (12b) for insertion into a bore, a second end defining a head (12a) and expander means (30) for expanding the diameter of the tube at least one location along the tube. The expander means comprises first (42) and second (44) expander/wedge elements arranged so that relative movement of the two elements causes the diameter of the tube to expand at that location. The first expander element (42) is mounted on an elongate rod (30) which is aligned generally along the longitudinal axis of the tube. Rotation of the rod (30) causes the relative movement of the two elements to cause the diameter of the tube to expand at the location. The rock bolt includes an arrestor (100) in the form of a ring, which defines an aperture which locates on the proximal end of the rod (30). The aperture is larger than the proximal end of the rod so that the arrestor is able to move along the proximal end of the rod. The arrestor includes a laterally extending protrusion (102) which locates in the longitudinal split (14) and is narrower than the longitudinal split and which is configured to engage with the head of the friction bolt when moved towards the proximal end of the friction bolt.