Abstract: A threaded bar construction and bar stock and nut combination useful in the mining industry and also in the concrete industry; the bar stock is provided with raised thread segments which appear only on one side of the elongate bar employed, so as to provide for marked reduction in manufacturing costs without detracting from the pull strength or tensioning parameters desired.

Abstract: A support sling, useful in the mining industry, for example, for supporting overhead loads such as mine roofs; the sling includes a pair of generally coplanar anchor lengths, sometimes called anchor bolts, having inwardly directed ends mutually facing each other and which, thus, are essentially coaxial; a similarly coaxial take-up coupling structure secures the ends and is constructed, either in active or passive mode, to restrain loads, acting under the force of gravity, from dilating downwardly to extreme conditions, and this in a manner as not to allow for the generation of serious force couples in the sling.

Abstract: Mine roof support systems, components and method, for supporting, whether in active or passive mode, mine roof strata; first and second, mutually spaced series of brackets are supplied for mounting to opposite sides of a mine roof span, and one or more cable assemblies are looped about such brackets and secured to the mine roof strata, such cable assemblies also being provided with take-up means: the invention is suitable and effective for supporting mine roof strata at various, desire mine locations.

Abstract: A mine support post having a yieldable mine post construction, made of metal and in telescoping form. The post of the invention comprises a pair of mutually telescoping metal post lengths. The innermost tubular post length has a medial bubble portion of enlarged girth which is oversize relative to the nominal inside diameter of the outermost tubular post length. The result, consequently, is not only to increase the frictional resistance between the post lengths but also to create a bubble zone characterized by elastic/plastic mutually inter-cooperating radial deformation and elastic stress-loading of the telescoping post construction, for further progressively increasing resistance of the composite post structure to compression end loading of such post. The yieldable mine post construction can be made adjustable and also radially preloaded and preset for immediate, desired load resistance.

Abstract: A yieldable mine post system having a yieldable mine post construction, made of metal and in telescoping form. The post of the invention comprises a pair of mutually telescoping metal post lengths. The innermost tubular post length has a medial bubble portion of enlarged girth which is oversize relative to the nominal inside diameter of the outermost tubular post length. The result, consequently, is not only to increase the frictional resistance between the post lengths but also to create a bubble zone characterized by elastic/plastic mutually inter-cooperating radial deformation and elastic stress-loading of the telescoping post construction, for further progressively increasing resistance of the composite post structure to compression end loading of such post. The yieldable mine post construction can be made adjustable and also radially preloaded and preset for immediate, desired load resistance.

Abstract: A mine roof truss and components thereof, the same including end support brackets, mine roof support plates, and associated structure. The truss structure is designed for maximum strength, and its mine roof support plates are designed for improving truss integrity and also for insuring that the stirrups used suitably preserve the integrity of the truss structure as well as provide safety features for stirrups to be placed under stress when such stirrups are loose or in a hanging position. The mine roof support plates utilized include depending horn portions having respective reaction surfaces for engaging stirrups to be placed in tension, and additionally, provide J-shaped lips forming cradles for the stirrups when the latter are in a hanging or loose position. In this way, the stirrups are preserved against dislodgement and free-fall within the mine which might contribute to a dangerous condition to workmen.

Abstract: A mine roof support truss and components thereof including support brackets and accommodating stirrups. In the truss construction, a pair of new type mine roof support brackets are utilized in combination with respective stirrups, the latter including interconnecting tie rod structure. The support brackets are unitary and preferably cast in construction, the same including the first portion having an upper bearing surface and a horn portion integral with and depending from such first portion. The horn portion is provided with a lower, upturned J-shaped lip which is useful for retaining a respective stirrup, which is designed to hang, when inactive, from the horn portion at the lip. During installation procedures, the stirrup associated with each horn portion of the respective brackets is elevated to horizontal position and the two stirrups tied together by tie rod means, with or without additional structure.

Abstract: A yieldable mine post, made of metal and in telescoping form. The post comprises a pair of mutually telescoping metal post lengths, one being slotted to receive selectively a chosen wedge for forced insertion within the slot to spread apart one of the post lengths, as to its diameter, whereby to increase surface friction between the post lengths and, thereby, the frictional resistance offered to progressive incremental displacements of one post length relative to the other in response to the downward movement of a mine roof supported by such post and further to cause resistance to sliding by forcing the outer post length to deform elastically outward and the inner post length to deform elastically inward, thus generating a "friction bubble" of "friction envelope" which progressively moves down the zone of pipe overlap.

Abstract: A truss structure, components, and method for trussing arched roofs in mines and the like. The truss structure includes, in addition to specially designed brackets and tensioned elongate connectors, one or more medially positioned upstanding post brackets for upwardly abuting against central portions of an arched mine roof. The method and concept includes, in a preferred form, applying obtuse-angle-oriented elongate connectors such as tie rods, secured to a lower portion of a post bracket concerned such that, when said elongate connectors are tensioned, an upward thrust is applied to said post brackets, whereby to produce an increased compression zone in the roof rock above the arched roof. Like-constructed interlocking roof truss structures are also provided for both longitudinally and also tranversely trussing an arched mine roof.

Abstract: Truss systems and components thereof for use in connection with supporting rock formations in underground mines, caverns, storage vaults, and so forth. Multiple types of truss brackets of unique design are incorporated in the various systems which also include tensioning tie rods and anchor bolts. The truss bracket components are designed so that a minimum or no force couples are exhibited when the tie rods employed are tightened down in their interconnection between associated truss brackets. Various truss systems accommodate mine entries, two-way, three-way, and four-way passageway configurements, and so forth. Additionally, provision is made for intercoupling trusses together.

Abstract: Structure and method for deterring cutter roof failure in underground mines such as coal mines. An elemental device of such structure comprises a unique bracket accommodating angulated bolting and having end-apertured flanges suitable for accommodating mutually horizontal tie rods disposed in tension. A series of the bracket devices are mutually spaced end-to-end and are longitudinally aligned parallel and generally proximate to a rib-roof juncture. Connecting tie rods intercoupling the bracket devices, are disposed in tension and, because of such, the roof strata proximate the roof-rib edge is placed longitudinally in compression. Truss support structures incorporating a plurality of devices can be made up to support and place in compression in large roof areas to deter roof failure. The method involved, for deterring cutter roof failure, is to provide, in one form of the invention, the said bracket devices and then anchoring the same over, e.g.

Abstract: A method of essentially maintaining the integrity of mine floors and precluding floor heave, this without the necessity of incorporating timber cribs, jacks and so forth, as utilized in the prior art. Floor integrity is maintained with a minimum of obstruction of the mine opening. Truss structures herein are designed to deter floor heave and, optionally, also may be adjusted in certain instances for employment as roof trusses even though stress patterns of the strata will differ. Truss-bracket, channel, and allied constructions are incorporated and are of advantageous design as hereinafter pointed out. Of special import is the bracket, of nominal triangular cross-section which facilitate through-placement of tie rods and anchor bolts in tension and in a manner deterring the generation of force couples. The truss structures will be installed between mine pillars, broadly defined as any side structure, rock or otherwise, spanned by a mine- or tunnel-roof.

Abstract: Truss systems and components thereof for use in connection with supporting rock formations in underground mines, caverns, storage vaults, and so forth. Multiple types of truss brackets of unique design are incorporated in the various systems which also include tensioning tie rods and anchor bolts. The truss bracket components are designed so that a minimum or no force couples are exhibited when the tie rod means employed are tightened down in their interconnection between associated truss brackets. Various truss systems accommodate mine entries, two-way, three-way, and four-way passageway configurements, and so forth. Additionally, provision is made for intercoupling trusses together.

Abstract: An elongate hollow rock bolt, bolt installations, and process of effecting the same, wherein the bolt is slightly over-size relative to the transverse cross-section of the mine roff hole or aperture in which the bolt is to be installed. The bolt has a radial, transverse polygonal cross-section formed by contiguous deflectable resilient sides provided with outwardly directed fins, the latter being tapered. When the bolt is impact-forced into a mine roof aperture, the fins are forced inwardly, deflecting the bolt sides which, owing to their resiliency, maintain the fins and the aperture wall areas contacting the same under compression, thus increasing the holding effect upon the bolt. The latter may be grouted in, and also may have a pre-installed bearing plate provided with an aperture and slide-slots accommodating the fins.

Abstract: Rock bolt structure and installation wherein the bolt takes the form of an elongate member having an enlarged head and also an elongate, blade-like shank. The opposite edges at the remote tip of the shank are slightly tapered, this to provide ease of installation in a rock formation hole or aperture. The width of the shank is designed so as to be slightly larger than the diameter of the hole. Thus, when the bolt is driven into the hole, there will be a friction fit and hence a frictional retention of the bolt at its edges by the hole wall. A bearing plate will be provided, the same having a slotted aperture to accommodate the blade-like shank of the bolt. Additionally, a relief aperture will be provided in the bearing plate to accommodate insertion of a grout fitting. The latter is supplied an impact tool, the same also having a relief aperture accommodating the head of the bolt. The opposite sides of the bolt shank are preferably roughened, i.e.

Abstract: An elongate hollow rock structure and installation wherein the elongated shank of the bolt is hollow and has a series of outwardly bowed side or side portions that are capable of resilient deflection. Fin means are provided in sides or side portion, with the overall span of the fin means being greater than the bolt hole into which the bolt is to be impacted. The pin means are tapered so as to provide for ease of insertion of the bolt. Impaction of the bolt into a mine roof hole provides for a compression loading of the fins of the bolt shank such that these engage the aperture wall in a forced-compression state. Corrosion factors are limited to fin edge contact with the aperture wall of the bolt hole. Resilient sides' deformation at the core of the bolt shank is relied upon to compression load the fins for frictional contact with the aperture wall into which the bolt is implaced.