Patent Application
20120034037
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. A flange may be provided on at least one of the roof support arm and the rib support arm projecting toward the mine roof or rib.
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 generally includes a support member may include a roof support arm and a rib support arm, and a curved junction portion between the roof support arm and the rib support arm. An aperture defined through the support member for receiving a mine roof bolt is located at the curved junction portion between the roof support arm and the rib support arm. The support member may be bent to form the roof support arm, rib support arm, and curved junction portion. The support member may include a base portion and an elongated reinforcement portion extending from the base portion and, alternatively, longitudinal edge portions extending angularly away from the base portion and terminating in edges. The aperture may be defined in the elongated reinforcement portion. The elongated reinforcement portion may be an embossment extending from a front surface of the support arm, for example a rib. This embodiment may also include a bearing plate having an upper edge and a lower edge, and defining a through-hole between the upper and lower plate edges, wherein the upper and lower plate edges are positioned in abutment with the roof support arm and rib support arm. A mine roof bolt may be included, wherein the bearing plate through-hole is operatively aligned with the curved junction portion aperture of the support member with the mine roof bolt extending therethrough.
In yet another embodiment, a method of supporting a rock formation includes positioning a support member including a roof support arm and rib support arm and a curved junction portion between the roof support arm and the rib support arm against an arched rock formation, wherein the curved junction portion defines an aperture therethrough. The roof support arm is positioned against a mine roof surface, the rib support arm is positioned against a mine rib surface, and the curved junction portion is positioned to align with the natural curvature of the arched rock formation. A bearing plate having an upper edge and a lower edge and defining a through-hole between the upper and lower plate edges is positioned against the support member such that the curved junction aperture of the support arm is operatively aligned with the plate through-hole. A mine roof bolt is extended through the plate through-hole and the curved junction portion aperture into engagement with the arched rock formation. The bearing plate is then compressed against the support member to maintain the support member in contact with the arched rock formation, 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 include torquing the mine roof bolt against the bearing plate. A mesh mat may also be positioned between the arched rock formation and the support member such that the support member contacts the mesh mat to maintain the mesh mat in contact with the arched rock formation. In this embodiment, the mine roof bolt may extend substantially vertically through the through-hole and the roof support arm aperture.
Another embodiment of the mine roof and rib support may include a support member having a roof support arm and a rib support arm, and a curved junction portion between the roof support arm and the rib support arm, wherein the roof support arm defines an aperture for receiving a mine roof bolt. A bearing plate having an upper edge and a lower edge, the bearing plate defining a through-hole provided between the upper and lower edges is positioned in abutment with the roof and rib support arms, respectively, with the through-hole being operatively aligned with the roof support arm aperture. A mine roof bolt extends through the through-hole of the bearing plate and the roof support arm aperture. The mine roof bolt is configured to compress the bearing plate against the support member, wherein the upper edge exerts a force against the roof support arm and the lower edge exerts a force against the rib support arm. The support member may include a second aperture on the roof support arm for receiving a second mine roof bolt. A second support member having a front surface and a back surface and defining an aperture for receiving a mine roof bolt may then be positioned over and received by the first support member with the second support member aperture being aligned with the second roof support arm aperture. A second mine roof bolt may then extend through the second support member aperture and the second roof support arm aperture. Both the first and second mine roof bolts may extend substantially vertically through their respective apertures. The rib support arm may also define an aperture for receiving a mine rib bolt, wherein the mine rib bolt extends through the rib support arm aperture in the mine rib.
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:
Referring now to the drawing 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
The angle θ between the roof 20 and rib 25 support arms can generally be about 90 degrees, since the angle α between the mine roof 50 and mine rib 55 is typically about 90 degrees. However, the angle θ between the arms 20, 25 can vary as needed, or desired, depending upon the angle between the mine roof 50 and the rib 55. Moreover, the angle α between the mine roof 50 and rib 55 may not be exactly 90 degrees, and the mine roof 50 and/or rib 55 may likely not be perfectly flat. Thus, embodiments of the support member 15 can be sufficiently flexible to compensate for variations in the angle α of the roof 50 and rib 55, and/or variations due to non-planar surfaces of the roof 50 and/or rib 55.
Referring to
Embodiments of the mine roof and rib support device 10 can further comprise a bearing plate 75 having an upper edge 80 and a lower edge 85, and a through-hole provided between the upper and lower edges 80, 85 through which the roof bolt 35 is installed. The bearing plate 75 can be positioned adjacent the support member 15 such that the upper and lower edges 80, 85 of the bearing plate 75 are positioned in abutment with the roof and rib support arms 20, 25, respectively. When the through-hole in the bearing plate 75 is operatively aligned with the aperture 30 in the support member 15 for installation of the roof bolt 35 therethrough, the upper and lower edges 80, 85 will apply force to the roof and rib support arms 20, 25, respectively, when force is applied to the bearing plate 75 during installation of the roof bolt 35. The roof bolt 35 can be installed at a 45 degree angle, but could be installed at a different angle if desired. When the mine roof bolt 35 is torqued against the outer surface of the bearing plate 75, a compressive load is applied to the bearing plate 75. The compressive load is distributed throughout the edges of the bearing plate 75. The compressive load is transmitted from the edges of the bearing plate 75 to the roof support arm 20 and the rib support arm 25, respectively, to compress the support arms 20, 25 against the roof 50 and rib 55 of the mine tunnel. The compressive forces cause the roof support arm 20 to exert pressure against the mine roof 50 and the rib support arm 25 to exert pressure against the mine rib 55.
One manner of creating the flanges 45, 47 is to cut tabs at the distal end 60, 65, typically of both the roof and rib support arms 20, 25, and then bend the tabs outwardly, away form the back of the channel, i.e., towards the mine roof and rib 50, 55, to form the flanges, 45, 47 to engage the mesh 70 that is commonly disposed over the mine roof and rib 50, 55, under the support member 15.
In certain embodiments, the dimensions corresponding to the reference characters in
The exemplary embodiments shown can comprise an elongated metal structural support member having a C-shaped cross-section that will typically be bent from a single length of material, and could instead be two separate pieces of material which are, e.g., welded together.
Another embodiment of the invention is shown in
Support member 102 includes a base portion 104 having a front surface 106 and a back surface 108. Integrally formed longitudinal flanges 110, 111 extend from base portion 104, such as at an angle, and terminate at respective edges 112, 113. Support member 102 further includes a reinforcement portion 114 extending from the base portion 104. Reinforcement portion 114 is illustrated as being positioned centrally on the support member 102 with aperture 130 defined therein and having a general V-shape, thereby forming a rib. The height of reinforcement portion 114 may be approximately equal to the height of longitudinal flanges 110, 111.
The mine roof and rib support device 100 may further include a bearing plate 175 having an upper edge 180 and a lower edge 185, and a through-hole provided between the upper and lower edges 180, 185 through which the roof bolt 35 is installed. Bearing plate 175 is shown as having a donut-style configuration with a reinforcing portion or embossment 190 surrounding the through-hole. The bearing plate 175 can be positioned adjacent the support member 102 such that the upper and lower edges 180, 185 of the bearing plate 175 are positioned in abutment with the roof and rib support arms 120, 125, respectively. In one embodiment, upper and lower edges 180, 185 each abut longitudinal flanges 110, 111 and reinforcement portion 114. When the through-hole in the bearing plate 75 is operatively aligned with the aperture 130 in the support member 102 for installation of the roof bolt 35 therethrough, the upper and lower edges 180, 185 will apply force to the roof and rib support arms 120, 125, respectively, when force is applied to the bearing plate 175 during installation of the roof bolt 35. The roof bolt 35 is installed at a 45 degree angle and may be installed at different angles. When the mine roof bolt 35 is tightened against the outer surface of the bearing plate 175, a compressive load is applied to the bearing plate 175. The compressive load is distributed throughout the edges of the bearing plate 175. The compressive load is transmitted from the edges of the bearing plate 175 to the roof support arm 120 and the rib support arm 125, respectively, to compress the support arms 120, 125 against the roof 50 and rib 55 of the mine tunnel. The compressive forces cause the roof support arm 120 to exert pressure against the mine roof 50 and the rib support arm 125 to exert pressure against the mine rib 55.
In one embodiment, support member 102 is produced from an elongated channel member which is bent to form roof support arm 120 and rib support arm 125. At the location of the bend, longitudinal flanges 110, 111 may become deformed as illustrated in
The support member 102 may include flanges 145, 147 provided on one or both of the ends of the respective roof support arm 120 and the rib support arm 125, wherein the flanges 145, 147 project toward the mine roof 50 or rib 55. A wire of mesh 70 may be positioned behind support arm 120 and over flange 145 in order to hold mesh 70 against the roof 50. Similarly, a wire of mesh 70 may be positioned behind rib support arm 125 and over flange 147 in order to hold mesh 70 against the rib 55.
In another embodiment, as shown in
As in the embodiments illustrated in
The mine roof and rib support device 200 may, again, further include a bearing plate 175 having an upper edge 180 and a lower edge 185, and a through-hole provided between the upper and lower edges 180, 185 through which the roof bolt 35 is installed. Bearing plate 175 is shown as having a donut-style configuration with a reinforcing portion or embossment 190 surrounding the through-hole. The bearing plate 175 can be positioned adjacent the curved support member 202 such that the upper and lower edges 180, 185 of the bearing plate 175 are positioned in abutment with the roof and rib support arms 220, 225, respectively. In this embodiment, the bearing plate 175, roof bolt 35, and curved support member 202 function in substantially the same way as described with respect to
The curved support member 202 may be produced from an elongated channel member which is bent to form roof support arm 220 and rib support arm 225. Unlike the embodiments illustrated in
Also, like the embodiments depicted in
Referring now to
As in the above-described embodiments, the curved support member 202 may include a base portion 104 having a front surface 106 and a back surface 108 with integrally formed longitudinal flanges 110, 111 extending from base portion 104 at an angle and terminating at respective edges 112, 113 and reinforcement portion 114 extending from the base portion 104.
The bearing plate 275, as shown in
Referring to
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.
Therefore, 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 ad scope of the appended claims.
