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: A method and apparatus for making a nut having a first end, a second end, and defining an orifice extending between the first end and the second end. A plurality of first threads are positioned in the orifice defined by the nut body, and a malformed thread is positioned in the orifice defined by the nut body, wherein the malformed thread interrupts continuity of at least one of the plurality of first threads.

Abstract: An expansion assembly configured to be attached to a mine roof bolt, wherein the expansion assembly may include a plug defining an interior cavity and an outer surface and an expansion shell having a plurality of spaced-apart prongs, preferably three prongs, and defining a plurality of shell grooves, wherein each of the spaced-apart prongs is oriented diametrically opposed to a corresponding shell groove.

Abstract: A mine roof bolt includes a flexible multi-strand cable having a first and second end with a drive head formed on the first head, the drive head having a plurality of driving faces on an exterior surface thereof. A load bearing barrel and wedge assembly is attached to the cable, with a separate drive head attached to the cable, wherein the separate drive head is utilized substantially for rotating the cable.

Abstract: A double ribbed bearing plate for use with a channel member in supporting a mine roof. The bearing plate includes a base with ribs in the bearing plate define recesses which receive flanges on the channel. The longitudinal edges of the bearing plate may extend below the plane of the base. When installed on a mine roof, the longitudinal edges may be spread apart upon changes in the load applied by the mine roof.

Abstract: A plurality of designs for mine roof bolts is disclosed. Each mine roof bolt includes a flexible multi-strand cable having a first and second end with a drive head formed on the first end, the drive head having a plurality of driving faces on an exterior surface thereof. The drive head may be formed integrally with the multi-strand cable in one embodiment of the present invention. An alternative embodiment of the present invention forms a drive head as a separate member. With a separate drive head, a barrel and wedge assembly may be attached to the cable wherein the drive head is utilized substantially for rotating the cable.

Abstract: A tensionable combination mine roof bolt is disclosed for use in resin grouted applications. The mine roof bolt includes a lower rod member having a rotatable bolt head at a first end thereof supporting a bearing plate and a threaded second end spaced from the first end. A coupling threadingly receives the lower rod member therein. A shearable stop device, such as a shear pin, is positioned within the coupling and adapted to stop the threaded lower rod member at a first position for rotation of the cable mine roof bolt during installation. After an upper portion of the cable mine roof bolt is secured, the shearable stop mechanism is subsequently sheared by the lower rod member to allow for tensioning of the cable mine roof bolt. A flexible multi-strand cable is coupled to the coupling device and forms the attachment point for the cable mine roof bolt.

Abstract: A tensionable mine roof cable bolt having a resin grouted upper portion and a mechanically anchored lower portion. The lower portion includes a shaft which is swaged to the cable and accepts a mechanical anchor. The cable bolt is rotated during installation in a mine roof to mix resin and simultaneously engage the mechanical anchor with the rock. A drivehead attached to the lower end of the cable fails upon tensioning of the bolt to a predetermined load.

Abstract: A steel alloy having 0.44-0.52 wt. % C, 1.1-1.6 wt. % Mn, 0.15-0.35 wt. % Si, a maximum of 0.04 wt. % P, a maximum of 0.05 wt. % S, a maximum of 0.45 wt. % Cu and 0.06-0.09 wt. % V. A No. 5 mine roof bolt formed from the steel alloy has a minimum yield strength of 90,000 psi. A mine roof bolt having a cross-sectional diameter of 7/8 inch or 1 inch and formed from the steel alloy has a minimum yield strength of 100,000 psi.

Abstract: A plurality of designs for mine roof bolts is disclosed. Each mine roof bolt includes a flexible multi-strand cable having a first and second end with a drivehead formed on the first end, the drivehead having a plurality of driving faces on an exterior surface thereof. The drivehead is a separate member. A barrel and wedge assembly is attached to the cable wherein the drivehead is utilized substantially for rotating the cable.

Abstract: A tensionable combination cable mine roof bolt is disclosed for use in resin grouted applications. The mine roof bolt includes a rod member having a rotatable bolt head at a first end thereof supporting a bearing plate and a threaded second end spaced from the first end. A coupling threadingly receives the rod member therein. A shearable stop device, such as a shear pin, is positioned within the coupling and adapted to stop the threaded rod member at a first position for rotation of the cable mine roof bolt during installation. After an upper portion of the cable mine roof bolt is secured, the shearable stop mechanism is subsequently sheared by the rod member to allow for tensioning of the cable mine roof bolt. A flexible multi-strand cable is coupled to the coupling device and forms the attachment point for the cable mine roof bolt.

Abstract: A mine roof bolt expansion anchor is formed from a plurality of identical shell segments. Each shell segment has a first end, a second end, and an end section at the first end. A first finger extends from the end section to the second end of the shell segment. A second finger extends from the end section toward the second end of the shell segment and terminates at a distal edge spaced from the second end of the shell segment. The end section, the first finger and the second finger each include an inner surface and an outer surface. A deformable coupling couples a plurality of shell segments together to form a multi-piece shell. The inside surfaces of the end sections, the first fingers and the second fingers of the multi-piece shell define a central aperture in which a wedge, adapted to coact with the plurality of shell segments, is received in the central aperture. Movement of the wedge from the second end to the first end of the shell segments forces the fingers to move in an outwardly direction.

Abstract: A flexible multi-strand steel cable of a preselected length is inserted in a bore hole drilled in a rock formation above an underground excavation. The cable includes an anchor end portion positioned in the bore hole for frictionally engaging the cable to the wall of the bore hole. The anchor end portion may also be chemically bonded to the surrounding rock formation. The cable extends out of the bore hole and includes a drive end portion that retains a bearing plate opposite the opening into the bore hole. The drive end portion includes a pair of diametrically positioned jaw members on the cable. The jaw members form a frustoconical outer surface positioned within a tapered bore of a collar. The collar advances on the jaw members to compress them into nonrotational gripping engagement with the steel cable. End portions of the jaw members extend out of the collar on the cable.

Abstract: A pair of truss brackets are secured to the roof of an underground passage adjacent to opposing ribs of the passage. The truss brackets each include a roof engaging surface and a truss supporting arm member extending from the roof engaging surface. A pair of U-bolts are supported by the arm members of the truss brackets. Each arm member extends horizontally from the truss bracket to an enlarged end portion of the arm member. The U-bolt is horizontally movable in a vertically hanging position on the arm member and is restrained by the enlarged end portion from disengagement from the arm member. The U-bolts are pivoted on the truss brackets to a horizontal position for connection to truss members which are connected to each other and tensioned to apply an uplifting force to the roof. As the truss members are connected and tensioned, the U-bolts are retained for a range of horizontal movement on the arm members to facilitate adjustments in the position of the U-bolts on the truss brackets.

Abstract: A bearing plate with side walls longer than end walls so that the bearing plate has a rectangular configuration and a continuous elliptical embossment extending along the side walls and the end walls of the plate. An aperture concentrically positioned at the midpoint of the plate. The plate has a bearing surface and an opposite surface, and the continuous elliptical embossment extends from the opposite surface continuously along and inwardly of the perimeter of the bearing plate. Inner embossed areas may extend from the opposite surface on either side of the aperture along the longitudinal axis.

Abstract: An elongated rod fabricated of polymeric material for use in reinforcing an underground passage includes an integral structure of a shaft portion, washer element and torque receiving end portion. The shaft portion is fabricated of a preselected polymeric material as required to meet the strength requirements of the rod in reinforcing the rock formation surrounding the passage. For use in reinforcing the side walls of a passage, the rod is fabricated of plastic material recycled, for example, from plastic beverage containers. The integral construction eliminates the need to thread the end of the rod to receive a nut. The washer element seats against a bearing block compressed against the side wall. When used with a resin system, the rod is anchored in the bore hole to maintain the bearing block compressed against the side wall to support the surrounding rock strata.

Abstract: In a longwall mining operation, a panel to be extracted is formed in a seam of mine material by longitudinally extending headgate and tailgate entries with the panel beginning in a set up room and ending at a termination line in a recovery room. The recovery room is developed in two stages. In the first stage, the recovery room extends the transverse width of the panel and extends from the termination line a preselected distance to a first sidewall. A roof control system is installed to support the rock strata over the initial width of the recovery room. A primary support system includes mechanical roof bolt assemblies installed in accordance with a preselected bolt pattern. The roof bolt assemblies are supplemented by trusses extending in spaced parallel relation a preselected distance apart from the termination line to the first sidewall. Channel members are secured in end to end relation to the roof closely adjacent to and parallel to the first sidewall.

Abstract: An elongated channel beam for supporting the surface of an underground rock formation includes a base portion with a bearing surface for contacting the rock strata and an opposite surface having a longitudinally extending central rib and flanged edges for resisting deflection and bending of the channel beam under the load of the rock strata. A plurality of openings spaced a preselected distance apart extend through the central rib. A bearing plate is positioned in overlying abutting relation with each opening in the channel beam. The bearing plate includes embossed areas and longitudinally flanged edges that overlie in abutting relation the central rib and flanged edges of the channel beam. The bearing plate is restrained from longitudinal and lateral movement on the channel beam. Anchor bolts extend through the aligned openings in the bearing plate and channel beam into bore holes drilled in the rock formation.

Abstract: An elongated rod fabricated of polymeric material for use in reinforcing an underground passage includes an integral structure of a shaft portion, washer element and torque receiving end portion. The shaft portion is fabricated of a preselected polymeric material as required to meet the strength requirements of the rod in reinforcing the rock formation surrounding the passage. For use in reinforcing the side walls of a passage, the rod is fabricated of plastic material recycled, for example, from plastic beverage containers. The integral construction eliminates the need to thread the end of the rod to receive a nut. The washer element seats against a bearing block compressed against the side wall. When used with a resin system, the rod is anchored in the bore hole to maintain the bearing block compressed against the side wall to support the surrounding rock strata.

Abstract: An elongated channel member for supporting the surface of an underground rock formation includes a base portion with a bearing surface for contacting the rock strata and an opposite surface having a longitudinally extending central rib and flanged edges for resisting deflection and bending of the channel member under the load of the rock strata. A plurality of openings spaced a preselected distance apart extend through the central rib. A bearing plate is positioned in overlying abutting relation with each opening in the channel member. The bearing plate includes embossed areas and longitudinally flanged edges that are complementary in shape with the central rib and flanges on the channel to securely engage the bearing plate on the channel member. Thus, the bearing plate engages the channel member to restrain longitudinal and lateral movement of the bearing plate on the channel member and stiffen the channel member to resist bending.