Abstract: An adjustable lattice girder includes a first lattice girder portion having a first end and a second end positioned opposite the first end, with the first lattice girder portion having a first connection member, and a second lattice girder portion having a first end and a second end positioned opposite the first end, with the second lattice girder portion having a second connection member configured to engage the first connection member. The first connection member is slidable relative to the second connection member between a first position corresponding to a first distance between the second end of the first lattice girder portion and the first end of the second lattice girder portion, and a second position corresponding to a second distance between the second end of the first lattice girder portion and the first end of the second lattice girder portion. The first distance different than the second distance.

Abstract: An adjustable lattice girder includes a first lattice girder portion having a first end and a second end positioned opposite the first end, with the first lattice girder portion having a first connection member, and a second lattice girder portion having a first end and a second end positioned opposite the first end, with the second lattice girder portion having a second connection member configured to engage the first connection member. The first connection member is slidable relative to the second connection member between a first position corresponding to a first distance between the second end of the first lattice girder portion and the first end of the second lattice girder portion, and a second position corresponding to a second distance between the second end of the first lattice girder portion and the first end of the second lattice girder portion. The first distance different than the second distance.

Abstract: A pumpable mine ventilation stopping wall structure comprised of a pumpable bag having spaced walls of generally parallel nonporous and flexible sheets with the sheets retained in spaced relationship with spaced flexible cross ties. The perimeter of the spaced walls may be closed off with a permeable mesh having a mesh size which will permit restricted flow of cementitious grout therethrough for sealing the wall structure to surrounding rough mine faces. The bag is provided with at least one grout fill port for filling the bag by pumping cementitious grout into the bag.

Abstract: A pumpable mine ventilation stopping wall structure comprised of a pumpable bag having spaced walls of generally parallel nonporous and flexible sheets with the sheets retained in spaced relationship with spaced flexible cross ties. The perimeter of the spaced walls may be closed off with a permeable mesh having a mesh size which will permit restricted flow of cementitious grout therethrough for sealing the wall structure to surrounding rough mine faces. The bag is provided with at least one grout fill port for filling the bag by pumping cementitious grout into the bag.

Abstract: An extraction and retrieval apparatus for highwall mining equipment which includes a mining head engaged with and proceeded by a series of push beams The apparatus includes a retriever platform having wing braces for bracing the retriever platform against a mine highwall and a hydraulic assembly is mounted on the retriever platform and includes at least a spaced pair of stop blocks securable to the retriever platform at multiple different positions therealong. The hydraulic assembly further includes a pull beam slidable along the retriever platform and having a connection for connecting the pull beam to an outer most exposed push beam of the mining equipment. A spaced pair of hydraulic cylinders are disposed between the pair of stop blocks and the pull beam for pulling a connected mining push beam together with attached mining equipment from the mine shaft.

Abstract: A retainment wall for underground horizontally extending mine shafts wherein a spaced vertical series of horizontal support ribs are secured to one or more upright supports that are secured in the mine shaft between the side walls thereof. Porous material covers and is secured to the forward retaining face of the wall structure. If the retainment wall structure is to be used as a fill retainment barrier the porous material is spray coated with a settable sealant which covers the forward face of the wall structure and the perimeter thereof to seal off the mine shaft.

Abstract: A retainment wall for underground horizontally extending mine shafts wherein a spaced vertical series of horizontal support ribs are secured to one or more upright supports that are secured in the mine shaft between the side walls thereof. Porous material covers and is secured to the forward retaining face of the wall structure. If the retainment wall structure is to be used as a fill retainment barrier the porous material is spray coated with a settable sealant which covers the forward face of the wall structure and the perimeter thereof to seal off the mine shaft.

Abstract: A pumpable mine ventilation stopping wall structure comprised of a pumpable bag having spaced walls of generally parallel nonporous and flexible sheets with the sheets retained in spaced relationship with spaced flexible cross ties. The perimeter of the spaced walls may be closed off with a permeable mesh having a mesh size which will permit restricted flow of cementitious grout therethrough for sealing the wall structure to surrounding rough mine faces. The bag is provided with at least one grout fill port for filling the bag by pumping cementitious grout into the bag.

Abstract: A pumpable mine ventilation stopping wall structure comprised of a pumpable bag having spaced walls of generally parallel nonporous and flexible sheets with the sheets retained in spaced relationship with spaced flexible cross ties. The perimeter of the spaced walls are closed off with a permeable mesh having a mesh size which will permit restricted flow of cementitious grout therethrough for sealing the wall structure to surrounding rough mine faces. The bag is provided with at least one grout fill port for filling the bag by pumping cementitious grout into the bag.

Abstract: A pumpable mine ventilation stopping wall structure comprised of a pumpable bag having spaced walls of generally parallel nonporous and flexible sheets with the sheets retained in spaced relationship with spaced flexible cross ties. The perimeter of the spaced walls are closed off with a permeable mesh having a mesh size which will permit restricted flow of cementitious grout therethrough for sealing the wall structure to surrounding rough mine faces. The bag is provided with at least one grout fill port for filling the bag by pumping cementitious grout into the bag.

Abstract: A mine rib support for bracing a vertical mine rib disposed between a mine floor and a mine roof. The support includes an elongated upright and continuous telescopically expandable support having a preset curvature. The member is longitudinally expanded for engaging the mine floor and the mine roof under compression with the curvature facing towards the mine rib. A support plate is laterally extended from the support member into compression engagement with the mine rib, thereby prestressing the support for support of the mine rib.

Abstract: An arch support assembly for withstanding the effects of rock burst in underground mines, which includes a spaced aligned series of arch supports, each support having a spaced pair of upright side support columns with an upwardly cambered cap beam arch having opposite ends therefore transversely meeting and secured respectively to the upper ends of the side columns at an obtuse angle. The arch supports are rigidly tied together and provided with a roof supported by the cap beams to provide in combination an arch support assembly.

Abstract: A liner is formed in an excavated spillway by providing a plurality of rectangular flexible liner sections with each liner section having a parallel series of elongated continuous and adjacent tubular pockets pre-filled with a dry cementitious material or a fine granular material. The liner sections are provided with a surrounding generally flat perimeter boarder. The liner sections are laid into the spillway with their boarders overlapping and the boarders are secured together with the tubular pockets aligned in the same direction to form a continuous liner blanketing the spillway. The tubular pockets are arranged in the spillway with their elongated sides presented to the expected direction of water flow in the spillway. The liner sections may be anchored to the spillway with anchor pins.

Abstract: A mine rib support for bracing a vertical mine rib disposed between a mine floor and a mine roof. The support includes an elongated upright and continuous telescopically expandable support having a preset curvature. The member is longitudinally expanded for engaging the mine floor and the mine roof under compression with the curvature facing towards the mine rib. A support plate is laterally extended from the support member into compression engagement with the mine rib, thereby prestressing the support for support of the mine rib.