Abstract: A system for re-tensioning mine roof channels includes a roof plate having a first side, a second side positioned opposite the first side, and a sidewall extending therebetween, where the first side is configured to engage a surface of a mine roof, and where the sidewall defines a radially extending slot configured to receive a mine roof bolt. The system also includes a spacer having a first side, a second side positioned opposite the first side, and a sidewall extending therebetween, with the first side of the spacer configured to engage with the second side of the roof plate, and the sidewall defining a slot configured to receive a mine roof bolt, and a nut having a first side, a second side positioned opposite the first side, a sidewall therebetween, and a threaded opening, with the sidewall defining a radially extending slot configured to receive a mine roof bolt.

Abstract: Disclosed are an anti-spalling blocking bar for a large cross-section coal gallery excavation work surface and a supporting method. The anti-spalling blocking bar comprises a blocking bar (1) and a support bar (7). Both a top portion of the blocking bar and an end of the support bar are provided with screw holes (2). A steel peg (5) is provided on an outer side of a bottom portion of the blocking bar. Locking teeth (6) is provided on an inner side of a mid-upper portion of the blocking bar, and a locking catch (8) is provided on one end of the support bar. The blocking bar and support bar are secured, using the screw hole and a screw bolt, to a temporary support device. After removing coal, a tool is used to hammer the blocking bar so as to wedge the steel peg thereof into a coalface (13). The locking catch of the support bar is held within the locking teeth to support a coal heading.

Abstract: A modular anchor has a metal plate having a pattern of holes around a periphery, the forming a boundary of a central inner area, a metal bracket having a raised central portion and parallel wings having upper and lower surfaces in parallel horizontal planes, with the bracket joined to the metal plate at a central location within the hole pattern, the wings and the metal plate coated with a material to facilitate heat welding to membrane; and a transition membrane positioned on the metal plate with the raised portion of the bracket extending upward through an opening in the transition membrane, and with the transition membrane heat welded to the upper surfaces of the wings of the bracket and to the metal plate everywhere within the central inner area, leaving the pattern of holes exposed.

Abstract: A method of installing a rock bolt is provided. A bolt hole can be formed by applying an insertion force to a drill rod and while the insertion force is being applied, applying a rotational force on the drill rod to rotate the drill rod and bore the bolt hole. A rock bolt can then be installed in the bolt hole by applying an insertion force to the rock bolt to insert the rock bolt into a bolt hole and while the insertion force is applied to the rock bolt, applying a rotational force on the rock bolt to rotate the rock bolt in the bolt hole. As the rotational force being applied to the rock bolt increases, the insertion force applied to the rock bolt can be decreased until no insertion force is being applied and the rock bolt has been torqued to a desired torque amount.

Abstract: A mine roof and rib support includes a support member comprising a roof support arm and a rib support arm, the roof support arm provided at an angle to the rib support arm, wherein the roof support arm defines an aperture for receiving a mine roof bolt; a bearing plate defining a through-hole, the bearing plate being positioned on the surface of the roof support arm, wherein the bearing plate through-hole is operatively aligned with the roof support arm aperture; and a mine roof bolt extending angularly through the through-hole of the bearing plate and the roof support arm aperture, the mine roof bolt being configured to compress the bearing plate against the support member. The bearing plate is positioned on the surface of the roof support arm away from the angled junction of the roof support arm and the rib support arm.

Abstract: Systems for installing roof support sheets on a mine roof. One system includes a support frame, a lifting system, and a feeding system. The support frame holds a plurality of roof support sheets. The lifting system lifts at least one of the sheets from the support frame. The feeding system obtains the at least one sheet from the lifting system and feeds the at least one sheet toward an installation apparatus for installation on the mine roof. The lifting system includes a shoe and at least one arm for moving the shoe to engage and move the at least one sheet. The feeding system includes a drive assembly and a support. The drive assembly engages and moves the at least one sheet toward the installation apparatus, and the support supports the at least one sheet moved by the drive assembly.

Abstract: A low profile tensionable bolt cable system and method of installation. The tensionable bolt cable has a tension cylinder with a constant diameter throughout its length and a threaded exterior. A bearing plate is provided with an opening and a first mating member. The tension cylinder has a proximal and a distal end with the proximal end having an angled interior surface and a longitudinally extending second mating member. The first and second mating members mate when the tension cylinder is inserted into the bearing plate. Angled wedges are inserted into the angled interior surface. A cable is inserted into the tension cylinder and between the wedges to hold the cable with respect to the tension cylinder to prevent the cable from twisting. A nut is threaded onto the tension cylinder, to tension the cable.

Abstract: In one aspect of the invention, an apparatus and related methods for installation in a borehole formed in a face of a mine passage comprises an elongated bolt including a spiral portion coated with a lubricity agent for positioning in the borehole; preferably, a fixing agent as well; and most preferably, a colored fixing agent. A hardened, stationary resin nut formed in only part of the borehole, preferably spaced from the distal end thereof, my receive the spiral portion of the bolt. Consequently, rotation of the spiral portion within the hardened resin nut serves to move the bolt within the borehole, such as for purposes of tensioning.

Abstract: A pan (10) and a pan system (100) for surface control of wall and/or roof material in a subterranean tunnel or room, the oval pan (10) having a convex central portion (20) held at an angle above a horizontal plane and an outermost edge angling downwards and meeting a planar pan edge portion (14) lying in the horizontal plane, both edges meeting at a transition point (16). The central portion includes a plurality of parallel concave rib members (18) arranged to span the shortest width of the pan. In use as a system (100), a bolt (40) drilled though a support plate (3) and the pan secures the pan system to the wall or roof. The force exerted onto the bolt transfers to the pan results in a dimpling of the central portion, allowing for a tighter application of the pan to the wall or roof.

Abstract: A mine roof bolt includes an elongated rod and a polymer coating layer. The elongated rod has a first end and a second end with a protruding portion extending radially outward from the elongated rod. The polymer coating layer covers at least a portion of the elongated rod between the first and second ends. The elongated rod is movable relative to the polymer coating layer in an axial direction. The elongated rod has a first position where the elongated rod has a predetermined axial position relative to the polymer coating layer and a second position where the elongated rod has a displaced axial position relative to the first position.

Abstract: A truss shoe for a roof support system includes a bolt receiving section, an intermediate section, and a housing having a threaded rod engaging section. The threaded rod engaging section has a passageway having a first open end spaced from, and in facing relationship to, the bolt receiving section and an opposite second end. The passageway has a threaded portion extending from the first end of the passageway toward the second end. A stop member is positioned spaced from the first open end of the passageway. With this arrangement, the end of the threaded rod passes through the space between the first open end of the passageway and the stop member into engagement with the stop member, whereby all of the threads of the threaded portion of the passageway are in engagement with the threads of the threaded bar.

Abstract: A spacer accessory including: a shank extending in an axial direction, one end of which includes a mechanism for securing the shank to a structural element of the wall that is to be lined and the other end of which includes a mechanism assembling the shank with lining studwork; two claws surrounding the shank; and a mechanism locking the two claws against one another with axial clamping.

Abstract: A stackable mine rock shield is disclosed. The mine rock shield includes a body having a first surface and a second surface, an aperture positioned at about the center of the body for receiving a fastening mechanism, a continuous protuberance extending outwardly from the first surface of the periphery of the body and defining a recess wherein the continuous protuberance intersects the first surface of the body to form an angle of intersection with such first surface, and an edge portion at the perimeter of the body. The mine rock shield may further include a rigid notch at the periphery of the body.

Abstract: A rock anchor (10) which includes a cable (12) with a hollow core, an expansion mechanism (20) at one end of the cable, a tube (14), which acts on a load washer (16), in which part of the cable is located, and a wedge (18) which locks the cable to the tube.

Abstract: A bolt anchor is comprised of a body and sleeve. The body is generally wedge shaped with a threaded bore along its axis and at least one stop near its smaller end. The sleeve has a round collar with leaves extending from the collar parallel to the axis of the collar and each other. The at least one stop maintains the assembly of the body and sleeve. Prongs on the sleeve prevent the retraction or turning of the bolt anchor when a bolt is installed in a hole using the bolt anchor. Reduced material thickness associated with the leaves on the sleeve produces hinges which allow the leaves to be more easily deformed outwardly to engage the sides of a hole. Inserting a bolt and bolt anchor assembly into the hole and then turning the bolt pulls the body into the sleeve and creates a wedging effect in the hole.

Abstract: A mine roof and rib support can be a support member having a roof support arm and a rib support arm, wherein the roof support arm is provided at an angle to the rib support arm. An aperture for a roof bolt is provided through the support member adjacent an intersection of the roof support arm and the rib support arm. A bearing plate having an upper edge and a lower edge, and a through-hole provided therebetween, can be provided wherein the upper and lower edges are positioned in abutment with the roof and rib support arms, respectively, to simultaneously apply force to each arm when a roof bolt is installed through each of the bearing plate and the support member. A flange can be provided at a distal end of one or both of the roof and rib support arms, each flange projecting toward the mine roof or rib.

Abstract: An end coupling for a shaft of a rock bolt comprises a body having a lead portion with a leading end, and a tail portion with a trailing end. The tail portion is arranged to be connected to a drive to impart rotation to the coupling about its axis. The body defines a passage extending between the leading and trailing ends and a first portion of the passage extends from the leading end and has a first diameter. A second portion of the passage is disposed adjacent the first portion and has a second diameter that is larger than said first diameter. A first thread extends along at least part of the first portion of the passage and is arranged to engage an external thread on the rock bolt shaft. A rock bolt assembly incorporating the end coupling is also disclosed.

Abstract: A high-strength anchor system for anchoring a support to mine strata is disclosed. The system includes an anchor plate and a connecting member on the anchor plate for connection of the support to the anchor plate. Anchor bolts extend through bolt holes in the anchor plate into bore holes in the mine strata. Load-spreading devices extend from respective bolt holes in the anchor plate into the bore holes. The load-spreading devices have outside diameters larger than outside diameters of the anchor bolts for spreading shear loads exerted on the anchor bolts over larger areas of the mine strata. A method of installing such a system and a safe room bulkhead using such a system are also disclosed.

Abstract: A mine roof and rib support may include a support member having a roof support arm provided at an angle to a rib support arm, the roof support arm defining an aperture for receiving a mine roof bolt, and wherein the support member defines a channel having an opened side surface and two legs extending from the opened side surface to contact the mine roof and the mine rib. A method of supporting a rock formation may include positioning a support member having a roof support arm provided at an angle to a rib support arm, wherein the roof support arm defines an aperture for receiving a mine roof bolt and a channel having an opened side surface and two legs extending from the opened side surface to contact the mine roof surface and the mine rib surface extending a mine roof bolt through the roof support arm aperture.

Abstract: A mine roof support includes a plate having a raised portion with an opening, and a mine and roof bolt, e.g. a barrel having a drive end and an opposite second end, and wedge assembly. The plate mates with a recess in a mine roof. In one embodiment, the second end of the barrel extends through the opening in the dome into a bore hole in the mine roof. In another embodiment, a second end of the mine bolt is contoured to match and fill the inner contour of the dome. A drill bit tool used to shape the recess includes a first bit, a second bit, and a third bit between the first and second bits to drill a bore hole, enlarge the end of the bore hole to receive the second end of the mine bolt, and to drill the recess.

Abstract: A tensioning assembly 10 for a cable bolt 11 comprises a clamping device (14, 16) adapted for fastening to the bolt and an outer member 18 adapted for interacting with the clamping device. The outer member 18 is able to undergo relative movement to the clamping device in the direction of the bolt's axis, and under such movement, the clamping device is caused to fasten to the bolt. Furthermore, the outer member is adapted for interacting with the bolt 11 whereby, during such relative movement, twisting of the bolt 11 with respect to the outer member 18 is restrained.

Abstract: A bolt anchor is comprised of a body and sleeve. The body is generally wedge shaped with a threaded bore along its axis and at least one stop near its smaller end. The sleeve has a round collar with leaves extending from the collar parallel to the axis of the collar and each other. The at least one stop maintains the assembly of the body and sleeve. Prongs on the sleeve prevent the retraction or turning of the bolt anchor when a bolt is installed in a hole using the bolt anchor. Reduced material thickness associated with the leaves on the sleeve produces hinges which allow the leaves to be more easily deformed outwardly to engage the sides of a hole. Inserting a bolt and bolt anchor assembly into the hole and then turning the bolt pulls the body into the sleeve and creates a wedging effect in the hole.

Abstract: An end coupling 1, 19 for a shaft 2 of a rock bolt 50 comprises a body 6 having a lead portion 8 with a leading end 9, and a tail portion 10 with a trailing end 11. The tail portion 10 is arranged to be connected to a drive to impart rotation to the coupling about its axis. The body 6 defines a passage 7 extending between the leading and trailing ends and a first portion 12 of the passage 7 extends from the leading end 9 and has a first diameter. A second portion 15 of the passage 7 is disposed adjacent the first portion 12 and has a second diameter that is larger than said first diameter. A first thread 14 extends along at least part of the first portion 12 of the passage 7 and is arranged to engage an external thread 4 on the rock bolt shaft 2. A rock bolt assembly incorporating the end coupling 1, 19 is also disclosed.

Abstract: A steel set assembly includes a first pair of legs and a second pair of legs with the first pair of legs being spaced from and positioned opposite the second pair of legs. First and second beams are provided with the first beam being secured to one leg of the first pair of legs and one leg of the second pair of legs. The second beam is secured to the other leg of the first pair of legs and the other leg of the second pair of legs. A panel is secured to the first and second beams and includes a base having a top surface and a bottom surface, a block having a top surface and a bottom surface, and a pad. The block is secured to the base and the pad is positioned between the top surface of the base and the bottom surface of the block.

Abstract: A mine roof and rib support can be a support member having a roof support arm and a rib support arm, wherein the roof support arm is provided at an angle to the rib support arm. An aperture for a roof bolt is provided through the support member adjacent an intersection of the roof support arm and the rib support arm. A bearing plate having an upper edge and a lower edge, and a through-hole provided therebetween, can be provided wherein the upper and lower edges are positioned in abutment with the roof and rib support arms, respectively, to simultaneously apply force to each arm when a roof bolt is installed through each of the bearing plate and the support member. A flange can be provided at a distal end of one or both of the roof and rib support arms, each flange projecting toward the mine roof or rib.

Abstract: In one aspect of the invention, an apparatus and related methods for installation in a borehole formed in a face of a mine passage comprises an elongated bolt including a spiral shaft portion for positioning in the borehole. A hardened, stationary resin nut formed in only part of the borehole, preferably spaced from the distal end thereof, receives the spiral shaft portion of the bolt. Consequently, rotation of the spiral shaft portion within the hardened resin nut serves to move the bolt within the borehole, such as for purposes of tensioning.

Abstract: A truss shoe for a mine roof truss comprises a base having a pair of ends, a curved side extending between the ends, a top side, and a bearing surface. The shoe includes an angled stanchion having a bore and a housing having a tapered bore, with a recess between the housing and stanchion. A retainer is sized to fit in the recess, with the retainer having an aperture disposed adjacent an end such that the blocks a portion of the opening of the bore in the housing to retain a wedge assembly in the tapered bore.

Abstract: A roof plate having a planar peripheral portion surrounding a dome. The dome portion defines an opening formed in a central portion therein and a tubular wall.

Abstract: A mine roof and rib support can be a support member having a roof support arm and a rib support arm, wherein the roof support arm is provided at an angle to the rib support arm. An aperture for a roof bolt is provided through the support member adjacent an intersection of the roof support arm and the rib support arm. A bearing plate having an upper edge and a lower edge, and a through-hole provided therebetween, can be provided wherein the upper and lower edges are positioned in abutment with the roof and rib support arms, respectively, to simultaneously apply force to each arm when a roof bolt is installed through each of the bearing plate and the support member. A flange can be provided at a distal end of one or both of the roof and rib support arms, each flange projecting toward the mine roof or rib.

Abstract: Cable bolt assemblies including tension cylinders and tension nuts, alone or in combination with cables and roof bearing plates, for use in underground mines to support mine roofs, are disclosed herein, as well as methods of securing roof cables to and within a mine roof for superior and immediate support. The cables have a first end securable within a borehole in a roof, a second end for exposure from the borehole, and a weight bearing nut secured to the second end. The tension cylinder accommodates, yet is not affixed to, the cable, and includes a threaded exterior surface and an interior cable-accommodating channel. The tension nut has a threaded interior surface complementary to the threaded exterior surface of the tension cylinder, and is rotatable about the tension cylinder.

Abstract: A mine roof and rib support can be a support member having a roof support arm and a rib support arm, wherein the roof support arm is provided at an angle to the rib support arm. An aperture for a roof bolt is provided through the support member adjacent an intersection of the roof support arm and the rib support arm. A bearing plate having an upper edge and a lower edge, and a through-hole provided therebetween, can be provided wherein the upper and lower edges are positioned in abutment with the roof and rib support arms, respectively, to simultaneously apply force to each arm when a roof bolt is installed through each of the bearing plate and the support member. A flange can be provided at a distal end of one or both of the roof and rib support arms, each flange projecting toward the mine roof or rib.

Abstract: A support member for supporting a roof of a subsurface space. The support member may include a base portion for defining a surface area to contact a ceiling of the subsurface space. One or more sockets may extend from the base for defining openings for receiving roof bolts therethrough. Accordingly, the support member may be configured to function as a washer for the roof bolts to support the roof material above the ceiling. The sockets may include covers for preventing the roof bolts from extending out of the sockets. The sockets may be oriented at angles with respect to the base such that when roof bolts are placed in the sockets, the roof bolts may extend at angles with respect to each other in a splayed configuration.

Abstract: A low-profile mine roof support device comprises a roof plate and a barrel. The barrel includes a nose portion, a shoulder portion, and a tapered bore for receiving a cable to secure the roof plate to the mine roof. The shoulder portion of the barrel comprises a convex surface that seats against the plate. So configured, a majority of the barrel, which includes the nose portion and the tapered bore, passes through the plate and into a drilled hole formed in the mine roof, thereby advantageously minimizing the extent to which the support device extends into the workspace of the mine without sacrificing the length of the barrel.

Abstract: A low-profile mine roof support device comprises a roof plate and a barrel. The barrel includes a nose portion, a shoulder portion, and a tapered bore for receiving a cable to secure the roof plate to the mine roof. The shoulder portion of the barrel comprises a convex surface that seats against the plate. So configured, a majority of the barrel, which includes the nose portion and the tapered bore, passes through the plate and into a drilled hole formed in the mine roof, thereby advantageously minimizing the extent to which the support device extends into the workspace of the mine without sacrificing the length of the barrel.

Abstract: A low-profile mine roof support device comprises a roof plate and a barrel. The roof plate is generally flat and defines a through-bore. The barrel includes a head disposed at a first end, and a cylindrical body disposed at a second end. A tapered bore extends from the first end of the barrel toward the second end, and is for receiving a cable. At least one wedge is adapted to be received within the tapered bore of the barrel to anchor the cable thereto. The head of the barrel comprises a convex surface that seats against the plate such that a portion of the head penetrates the bore and intersects the first and second planes, thereby reducing the extent to which the support device extends into the mine without sacrificing the working length of the barrel.

Abstract: A support member for supporting a roof of a subsurface space. The support member may include a base portion for defining a surface area to contact a ceiling of the subsurface space. One or more sockets may extend from the base for defining openings for receiving roof bolts therethrough. Accordingly, the support member may be configured to function as a washer for the roof bolts to support the roof material above the ceiling. The sockets may include covers for preventing the roof bolts from extending out of the sockets. The sockets may be oriented at angles with respect to the base such that when roof bolts are placed in the sockets, the roof bolts may extend at angles with respect to each other in a splayed configuration.

Abstract: A resin bonded mine roof bolt having an elongated rod with a first end and a second end. A segmented resin compression layer covers a portion of the rod below the first end. When installed in a mine roof bore hole with curable resin, the resin compression layer mixes the resin and partially fills the bore hole to minimize the amount of resin needed to anchor the bolt. Individual segments of the layer are tapered to create a wedging force on resin with the bore hole.

Abstract: Disclosed is a mine roof and rib support system generally including a square bearing plate. A through hole is positioned near a center portion of the square bearing plate. A peripheral section at least partially circumscribes the bearing plate. In between the through hole and the peripheral section is a rib member area. The rib member area may include two rib members with a convex cross-section connected by a substantially linear surface member disposed between the two rib members, two or more concave ribs with a substantially linear surface member disposed between the two rib members, or two substantially linear surfaces connected by a convex rib member. A safety edge surrounds the square bearing plate. The safety edge may be a rolled edge, a looped edge, a folded edge, or another comparable edge. Also disclosed is a method for making the mine roof and rib support system.

Abstract: The present invention is related to a rock bolt (7), expandable by means of a pressure media, for insertion into a borehole. The expandable bolt (7) comprises a connection unit (8) with means (11) for detachable interaction with an expansion means (10) for expansion of the rock bolt (7), as well as with a suspension element (16). The connection unit is designed with such external dimensions so that it may be inserted into the bore-hole. The invention also relates to such a rock bolting system.

Abstract: A truss shoe for a roof support system includes a base member having a bearing surface and, optionally, an end having a sweeping radius for ease of moving the truss shoe into an installation position, a bolt receiving section having a bore hole, a cable engaging section, and an intermediate section. The cable engaging section includes an opening and a slot and, optionally, a lock-in device that allows a cable to move through the slot into the opening and retains the cable in the opening. In another non-limiting embodiment of the cable engaging section, the cable is moved into an assembly mounted in a conical-shaped passageway of the cable engaging section to compress the assembly around the cable. The intermediate portion includes a pair of side flanges on the base member between the bore and the opening and, optionally, a rib between the pair of side flanges.

Abstract: An improved mine roof bolt is disclosed. The mine roof bolt comprises a bolt portion having a threaded end, a slidable camming nut, a stop, and an expansion shell having a central threaded nut with wedge fingers extending from it. The camming nut is fitted into the expansion shell which is threaded onto the threaded section of the bolt. Turning the bolt while it is in a hole causes the expansion shell to move along the bolt and carry the camming nut to the stop located on the bolt, and this causes the wedge fingers to engage with the camming nut, spreading the wedge fingers into contact with the hole sides. As the turning of the bolt continues, the relative movement of the camming nut and wedge fingers increases the wedging effect within the hole until the bolt is anchored in the hole. While turning of the bolt may serve to mix a catalytic adhesive, the adhesive is not needed to activate the mechanical anchoring mechanism of the mine roof bolt.

Abstract: An adjustable yield rock bolt that comprises an elongated tensile support member that interacts with at least one gouging member and a receiving member capable of receiving the elongated tensile support member and hold the gouging member segment there between, wherein the elongated tensile support member extends beyond the receiving member a length that corresponds to a predetermined amount of yield before ultimate failure. The bolt has adjustability by allowing for controlled yield by gouging of the elongated tensile support member for any length of displacement.

Abstract: A truss shoe for use on a mine roof truss having at least one inclined bolt and at least one horizontal cross member comprises a base including a first end, a second end, a first side and a second side extending between the first and second ends, a generally planar bearing surface, and a top side disposed opposite the bearing surface, the bearing surface arranged for contact with the mine roof. A stanchion is formed on the top side and includes a bore extending from a top end of the stanchion through the bearing surface, the bore sized to receive the inclined bolt. A bracket is formed on the top side and includes a laterally extending slotted bore sized to receive the horizontal bolt. A portion of the first end and a portion of the first side cooperate to form a curved edge.

Abstract: A resin bonded mine roof bolt having an elongated rod with a drive head at one end and an expansion anchor threaded onto the other end. A segmented resin compression layer covers a portion of the rod below the expansion anchor. When installed in a mine roof bore hole with curable resin, the resin compression layer mixes the resin and partially fills the bore hole to minimize the amount of resin needed to anchor the bolt. Individual segments of the layer are tapered to create a wedging force on resin with the bore hole. The expansion anchor is expandable upon initial hardening of the resin to tension the bolt.

Abstract: A roof bolt comprises a shaft for insertion in a hole drilled in a mine roof and a head whereby the bolt may be rotated, the head being offset with respect to the longitudinal axis of the shaft so that when the bolt is rotated by means of its head the shaft is caused to describe a circle of greater diameter than its own diameter, and where the offset is at least 0.08 inch and not more than 0.25 inch. Preferably the offset is from 0.10 to 0.16 inch. The invention includes a method for the production of roof bolts which comprise a shaft for insertion in a hole drilled in a mine roof and a head whereby the bolt may be rotated, the method being characterised by being controlled so that at least 90% of the bolts produced have their head central axis offset with respect to the longitudinal axis of the shaft by an amount of at least about 0.08 inch and not more than about 0.25 inch.

Abstract: An improved apparatus for ground support comprising a tensionable reinforcing member including at least one nut threadably receivable by the tensionable reinforcing member. The nut body comprises a squared portion and a convex hemispherical portion. The nut includes a bore adapted for engagement with the first end threaded portion of the tensionable reinforcing member. The nut also at least one second bore transversing the squared portion of the nut square body portion. The second bore is adapted to accept a shearing element capable to fix the nut in a temporary first operating position on the reinforcing member. The shearing element is a rolled member made from carbon steel. The shearing element is adapted to shear at a consistent and predetermined torqueshear.

Abstract: The invention comprises a roof bolt and nut in screw threaded engagement, said bolt comprising a shaft for insertion in a hole drilled in a mine roof and a threaded portion engaged by the nut whereby the bolt may be rotated. The nut is offset with respect to the longitudinal axis of the shaft of the bolt so that when the bolt is rotated by means of the nut, the bolt is caused to describe a circle of greater diameter than its own diameter, the amount of said offset being from about 0.015 to about 0.50 inches. Preferably the offset is from about 0.02 to about 0.25 inches. The nut may be releasably locked in screw threaded engagement with the bolt so that the bolt can be rotated by means of the nut and above a selected torque the nut will break out.

Abstract: An improved mine roof bolt is disclosed. The mine roof bolt comprises a bolt portion having a camming nut rigidly fixed to it and a threaded end and an expansion shell having a central threaded nut with wedge fingers extending from it. The expansion shell is threaded onto the threaded section of the bolt. Turning the bolt while it is in a hole causes the expansion shell to move along the bolt and brings the wedge fingers into contact with the camming nut, spreading the wedge fingers into contact with the hole sides. As the turning of the bolt continues, the relative movement of the camming nut and wedge fingers increases the wedging effect within the hole until the bolt is anchored in the hole. While turning of the bolt may serve to mix a catalytic adhesive, the adhesive is not needed to activate the mechanical anchoring mechanism of the mine roof bolt.

Abstract: Roof bolt bearing plate and method are disclosed for use in underground mining operations. A dome-shaped roof bolt bearing plate and method support the roof in a mine. The bearing plate is round or elliptical different from conventional commercial roof support devices. No dangerous edges and corners protrude downward. A recessed center is lower than the outer rim. A thin outer rim conforms to roof irregularities. The roof bolt bearing plate and method have been found to provide important advantages over conventional commercial roof support devices, including (1) concealing the head of the roof bolt to a preferred degree, (2) conforming to the roof's irregularities which will cause causing the plate to remain tight, (3) provide readability so the installer can to determine the quality and integrity of installation and anchorage, and (4) compressing the lower strata of the mine roof, thereby and creating a beam like support for the upper layers of the mine roof.

Abstract: A truss has a pair of parallel and longitudinally extending chord rods and transverse rods interconnecting the chord rods. First and second slides each have a pair of tubes each fitting over a respective one of the chord rods and slidable longitudinally therealong and a cross member rigidly interconnecting the tubes and formed with a throughgoing hole through which passes a respective anchor member projecting from a tunnel or mine wall. The slides can be longitudinally fixed on the rods.