1. Field of the Invention
The support member relates generally to mine surface control, and more particularly to a mine roof and rib support with a roof support arm and a rib support arm which simultaneously support the mine roof and mine rib.
Mine roof and rib supports are commonly used in underground mining, excavating, and tunneling operations to support and control the overhead and lateral rock strata. In one conventional mine surface control system, a series of bore holes can be drilled into the mine roof or rib; a mine roof bolt can be installed in the bore hole; a channel, bearing plate, or mat can be positioned between the end of the mine roof bolt; and the mine roof or rib, and the mine roof bolt can be anchored in the bore hole and tensioned such that the mine roof bolt and channel, bearing plate, or mat exert a compressive force upon the mine roof and rib to prevent deterioration of the overhead and lateral rock strata.
2. Description of Related Art
Some examples of mine roof and rib support systems are described in U.S. Pat. No. 4,456,405 to Galis entitled “Mine Roof Truss Assembly and Associated Method”; U.S. Pat. Nos. 5,385,433; 5,202,209; and RE 35,902 to Calandra, Jr. et al. entitled “Bearing Plate’; U.S. Pat. No. 4,960,348 to Seegmiller entitled “Truss Systems, Components, and Methods for Trussing Arched Mine Roofs”; U.S. Pat. No. 4,775,266 to Seegmiller entitled “Structure and Method for Deterring Cuter Roof Failure”; and U.S. Pat. No. 4,630,974 to Sherman entitled “Roof Support System for a Mine and Method for Providing the Same”.
An embodiment of the mine roof and rib support device may comprise a support member having a front surface and a back surface, a base portion, a roof support arm, a rib support arm, a bearing plate and a mine roof bolt. The roof support arm is provided at an angle to the rib support arm and comprises at least one aperture therethrough. The bearing plate may comprise an upper edge and a lower edge and a through-hole defined therethrough positioned between the upper and lower edges. The upper and lower edges of the bearing plate can be positioned in abutment with the roof and rib support arms, respectively, with the through-hole being aligned with the aperture through the support member. The mine roof bolt extends through the through-hole of the bearing plate and the aperture of the roof support arm. The mine roof bolt compresses the bearing plate against the support member, such that the upper edge exerts a force against the roof support arm and the lower edge exerts a force against the rib support arm. The mine roof bolt may extend vertically through the through-hole and the aperture of the roof support arm. The roof support arm may alternatively comprise a second aperture for receiving a second mine roof bolt. The angle between the roof and rib support arms can generally be about 90 degrees to generally correspond to usual angles between the mine roof and the mine rib, but the angle can be different if needed.
The bearing plate may comprise side edges that are longer than the upper and lower edges and may further comprise a loop shaped embossment that surrounds the through-hole. In this embodiment, the through-hole may be off-centered, located at a position on the bearing plate that is closer to the upper edge of the bearing plate than the lower edge.
In another embodiment, the support member can further comprise a reinforcement portion that extends from the base portion. The reinforcement portion may take the form of an embossment extending from the front surface of the support member. The support member may further comprise a longitudinal flange edge portion extending angularly away from the base portion and terminating in edges. The upper and lower edges of the bearing plate may then be positioned in abutment with the longitudinal flange edge portions and/or the reinforcement portion of the support member. Further, the aperture of the roof support arm of the support member may be defined in the elongated reinforcement portion. A flange may be provided on one, or both, of the roof support arm and the rib support arm, wherein the flange extends angularly away from the front surface toward the back surface of the support member, toward the mine roof and/or rib, respectively. The flanges can be bent from the distal ends of each of the roof and rib support arms to hold the mesh that can commonly be provided between the support arm and the mine roof and/or rib.
The mine roof bolt, or tensioning nut, can be torqued against the bearing plate such that the upper and lower edges of the bearing plate simultaneously exert force on each of the roof support arm and the rib support arm.
One embodiment of the present invention is directed to a method of supporting a rock formation. A support member having a roof support arm and a rib support arm is provided, and the roof support arm is positioned against a mine roof surface and the rib support arm is positioned against the mine rib surface. A bearing plate is positioned against the support member. The bearing plate has an upper edge, a lower edge and a through-hole. The bearing plate is positioned such that the through-hole is aligned with an aperture in the roof support arm. A mine roof bolt is extended through the through-hole and the aperture in the roof support arm to engage the mine roof surface. The bearing plate is compressed against the support member such that the upper edge of the bearing plate is positioned in abutment with the roof support arm and the lower edge of the bearing plate is positioned in abutment with the rib support arm. Compressing the bearing plate against the support member may comprise torquing the mine roof bolt against the bearing plate. The mine roof bolt may be vertically extended through the through-hole and aperture. The support member may be provided by bending a support member to form the roof support arm at an angle to the rib support arm. The angle may be 90 degrees.
Another embodiment of the present invention is directed to a mine and roof rib support system comprising a front surface and a back surface, a base portion, a roof support arm and a rib support arm. The roof support arm is provided at an angle to the rib support arm and comprises a first aperture and a second aperture defined therethrough. The system comprises a bearing plate comprising an upper edge and a lower edge and defining a through-hole therethrough positioned between the upper and lower edges. The upper and lower edges of the bearing plate can be positioned in abutment with the roof and rib support arms, respectively, with the through-hole being aligned with the aperture through the support member. A first mine roof bolt extends through the through-hole of the bearing plate and the first aperture of the roof support arm. The mine roof bolt compresses the bearing plate against the support member, such that the upper edge exerts a force against the roof support arm and the lower edge exerts a force against the rib support arm. The system includes a second support member comprising a front surface and a back surface and defining an aperture for receiving a mine roof bolt. The first support member receives the second support member with the aperture of the second support member being aligned with the second roof support arm aperture. A second mine roof bolt extends through the second support member aperture and the second roof support arm aperture. The mine roof bolts may extend vertically through their respective apertures and/or the bearing plate through-hole. The system may further comprise a mine rib bolt for extending through an aperture defined through the rib support arm.
To the accomplishment of the foregoing and related ends, certain illustrative aspects of the mine roof and rib support device are described in the following description and drawing figures. These aspects may be indicative of but a few of the various ways in which the principles of the mine roof and rib support device may be employed, and which is intended to include all such aspects and any equivalents thereof. Other advantages and features of the mine roof and rib support may become apparent from the following detailed description when considered in conjunction with the drawing figures.
A more complete understanding of the mine roof and rib support can be obtained by considering the following description in conjunction with the accompanying drawing figures in which:
As used herein, the term “upwardly” shall refer to a direction with respect to a mine passageway which is oriented generally along the direction extending from the mine floor to the mine roof, the term “downwardly” shall refer to a direction with respect to a mine passageway which is oriented generally along the direction extending from the mine roof to the mine floor, the term “outwardly” shall refer to an orientation generally in transverse direction extending from the walls of the passageway to the mine passageway central longitudinal axis, and the term “inwardly” shall refer to an orientation generally in transverse direction extending from the central longitudinal axis of the mine passageway to the walls of the passageway.
Referring now to the figures in which like reference numbers refer to like elements, a perspective view of an embodiment of a mine roof and rib support device 10 is shown in
Referring to
Referring to
Support member 15 may further include, for example, a base portion 90 having a front surface 92 and a back surface 94. Referring to FIGS. 2 and 5-7, integrally formed longitudinal flanges 102, 104 extend from base portion 90 at an angle, for example, and terminate at respective edges 106, 108. Support member 15 further includes a reinforcement portion 110 extending from the base portion 90. Reinforcement portion 110 is illustrated as being positioned centrally on the support member 15 and comprising a general V-shape embossment, thereby forming a rib with aperture 30 defined therein. The height of reinforcement portion 110 may be approximately equal to the height of longitudinal flanges 102, 104.
The mine roof and rib support device 10 may further include a bearing plate 75, illustrated in
In one embodiment, for example, support member 15 is produced from an elongated member which is bent to form roof support arm 20 and rib support arm 25. The channel can be heated to facilitate the bending process. At the location of the bend 40, longitudinal flanges 102, 104 may become deformed as illustrated in
The support member 15 may be configured to be stackable for ease of transport by including the angled longitudinal flanges 102, 104. The front surface 92 of one support member 15 may receive at least a portion of a back surface 94 of another support member 15. While the entire front surface 92 of one support member 15 may not completely receive the entire back surface 94 of another support member 15, the support members 15 may nest within each other, thereby reducing the overall footprint of multiple stacked support members 15 as compared to multiple unstackable support members 15.
The dimensions corresponding to the reference characters in
Referring to
The embodiments illustrated have shown an elongated structural support member 15 bent from a single length of material; however, alternatively, support member 15 could instead be two separate pieces of material which are, e.g., welded together.
What has been described above includes exemplary embodiments of a mine roof and rib support having a roof support arm and a rib support arm that can support both the roof and rib of the mine at the same time. It is, of course, not possible to describe every conceivable combination of components or methodologies for purposes of this description, but one of ordinary skill in the art may recognize that further combinations and permutations are possible in light of the overall teaching of this disclosure. Accordingly, the description provided herein is intended to be illustrative only, and should be considered to embrace any and all alterations, modifications, and/or variations that fall within the spirit and scope of the appended claims.