THEREOF

TECHNICAL FIELD

[0001] The presently disclosed subject matter generally relates to the field of devices for use in underground mines. Particularly, the present subject matter relates to a bulkhead for facilitating backfilling of a stope upon mining thereof.

BACKGROUND

[0002] Typically, upon mining ore from an underground mine in, or with use of, a stope mining process, the exposed stope would need to be backfilled in order to prevent, or avoid, the surrounding ore, or earth, from caving, or collapsing, onto other regions, for example, an access tunnel, or a brow, that is adjacent to, or adjoining, the stope. In many conventionally known practices of stope mining, an embankment is formed in the shape of a bund or a mound. Such bund, or mound, is typically developed using loose, or flowable, materials including, but not limited to, sand, stone, or other materials. These flowable materials are known to offer rigidity only as a mere result of their bulk, or volume, of the materials themselves in withstanding forces that are likely to be encountered during the backfilling process. However, such an embankment, despite being positioned at a leading edge of the stope i.e., adjoining the brow of the stope, would have a large space claim owing to the large amount of material that is required for effectively creating the embankment with adequate strength to withstand the aforementioned forces. An order of such a large space claim may include a pre-determined distance, for example, up to 5 or 10 meters behind the leading edge or brow of the stope.

[0003] A secondary material, for example, backfilling paste or concrete poured into the stope and up to the embankment may, owing to a poor process design with use of the embankment, spill, at least partly or wholly, over the embankment and cause the backfilled material to become excessive i.e., more than that required by mining personnel for backfilling the stope alone. Consequently, a protective wall that is formed upon hardening of the secondary material would he at an even greater distance from the backfilled stope, i.e., further behind the embankment due to the large space claim of the embankment itself. For example, a distance of the protective wall from the leading edge, or brow, of the stope may now lie in the range of 7 to 12 meters. Moreover, upon hardening of the excessive backfilled material, this excessive backfilled material would need to be removed, for instance, by blasting and carrying away the blasted material to another location before resuming mining of the access tunnel or an adjacent stope in the ore. Carrying out such extraneous operations prior to resuming mining causes a significant amount of downtime in regards to an actual mining operation while also incurring additional time, effort, and costs that could reduce profitability and overall revenue to mining personnel/company.

[0004] In view of the aforementioned drawbacks, typically associated with creation of mound- like embankments having a large space-claim, there exists a need for a compact yet sturdy protective barrier that obviates the need for increased space requirements while also facilitating mining personnel/company to eliminate, or at least minimize, excessive material that would otherwise be needed to backfill the stope, blasting the excessive material upon hardening, and transporting the blasted material each of which is known to generate significant amounts of waste. Further, for the aforementioned reasons, it would, therefore, be prudent to implement a protective barrier that is simple to manufacture, or assemble, yet easy to use in facilitating backfilling of the stope upon mining.

SUMMARY

[0005] To overcome the above-mentioned limitations and problems, the present disclosure provides a bulkhead for use in facilitating backfilling of the stope upon mining. The bulkhead of the present disclosure is simple to manufacture, or assemble, yet easy to use. Further, when not in use, the bulkhead can be folded so as to have a compact configuration i.e., size and shape. Furthermore, in use, the bulkhead can be set up by mining personnel fairly easily and quickly, for example, in an hour or less. Prior to being used in the backfilling operation, the bulkhead of the present disclosure is sprayed with shotcrete and thereafter loaded with weight i.e., using a weighted member. Consequently, the bulkhead disclosed herein is sturdy to adequately support, or withstand, the forces that are likely to be encountered during the backfilling process. Although it has been disclosed herein that the weighted member is used to load the bulkhead with added weight, it is neither suggested, nor necessary. The bulkhead of the present disclosure can withstand the forces encountered during the backfilling process once it has been merely sprayed with shotcrete i.e., without the need for added load that would otherwise result from use of the weighted member. Moreover, the bulkhead of the present disclosure offers additional flexibility to mining personnel in that the bulkhead may be varied in size to meet one or more requirements pertaining to an aspect ratio i.e., height and/or width of an access tunnel, or a brow, adjoining the stope.

[0006] An embodiment of the present disclosure provides a bulkhead for use in facilitating backfilling of a stope upon mining thereof. The bulkhead includes a skid having a base and a pair of post members extending upwardly from the base. The bulkhead also includes a barrier having a primary grid assembly pivotally supported on the pair of post members, at least one secondary grid assembly selectively, and sequentially, stacked upon the primary grid assembly; and a brace selectively stacked upon a uppermost one of the primary grid assembly and the at least one secondary grid assembly. An aspect ratio of the barrier, prior to, backfilling, is operably adjustable by individually adjusting one or more of the primary grid assembly, the secondary grid assembly and the brace to confirm with an aspect ratio of an access tunnel, or a brow, adjacent to the stope for subsequently facilitating backfilling of the stope.

[0007] According to an aspect of the present disclosure, the base of the skid further comprises a pair of legs attached to a bottom portion of the pair of post members. Also, each leg from the pair of legs is equidistantly spaced apart from a mid-plane of the skid with a pre-determined distance therebetween.

[0008] According to a further aspect of the present disclosure, the skid further includes a pair of inclined support members angularly extending between, and attached to, a rear portion of the pair of legs and a top portion of the pair of post members.

[0009] According to a further aspect of the present disclosure, the bulkhead also comprises a weighted member having a pair of holes in alignment with corresponding ones of the pair of legs of the base. The weighted member is slidably, and releasably, engaged with a front portion of the pair of legs upon receipt of the pair of legs within the pair of holes.

[0010] According to a further aspect of the present disclosure, the weighted member is further configured to define at least one horizontal passageway defined therethrough, and wherein the weighted member includes at least one elongated bollard axially disposed within the at least one horizontal passageway.

[0011] According to another aspect of the present disclosure, the primary grid assembly includes at least one first grid member and at least one second grid member pivotally coupled to corresponding ones of the pair of post members using hinges. [0012] According to a further aspect of the present disclosure, each of the first and second grid members further include an arcuate stationary rear screen and a correspondingly arcuate front screen slidably moveable in relation to the arcuate stationary rear screen, and wherein each of the front and rear screens have a concave front side and a convex rear side.

[0013] According to a further aspect of the present disclosure, the arcuate front screens of the primary grid assembly has distally located ends that are adapted to be secured with corresponding sidewalls of the access tunnel, or the brow, upon slidably moving the front screen in relation to the stationary rear screen.

[0014] According to a further aspect of the present disclosure, the barrier further comprises one or more upright support bars extending along the convex rear side of the arcuate rear screens, the upright support bars having top portions defining axially upright primary receptacles therein. [0015] According to a further aspect of the present disclosure, each secondary grid assembly of the barrier comprises a third grid member and a fourth grid member pivotally connected to each other, wherein each of the third and fourth grid members further includes locating pins depending downwardly to engage with corresponding ones of the axially upright primary receptacles defined in top portions of the upright support bars for rendering the at least one secondary grid assembly co-planar with the primary grid assembly when stacked sequentially upon the primary grid assembly.

[0016] According to a further aspect of the present disclosure, each of the third and fourth grid members further include an arcuate stationary rear screen and a correspondingly arcuate front screen slidably moveable in relation to the arcuate stationary rear screen, and wherein each of the front and rear screens have a concave front side and a convex rear side.

[0017] According to a further aspect of the present disclosure, the slidably moveable front screens of the primary grid assembly have distally located ends that are adapted to be secured to corresponding sidewalls of the access tunnel, or the brow, that are adjacent to the stope upon slidably moving the front screen in relation to the stationary rear screen.

[0018] According to a further aspect of the present disclosure, the locating pins from each of the third and fourth grid members extend upwardly to define a secondary receptacle in alignment with the primary receptacle to facilitate a stacking of another one of the at least one secondary grid assembly or the brace. [0019] According to a further aspect of the present disclosure, the brace includes at least two upright members received axially, and at least partly, within the primary receptacles or the secondary receptacles corresponding to the uppermost one of the primary grid assembly and the secondary grid assembly, if stacked upon the primary grid assembly. Further, the brace also includes an arcuate tube member independently, and slidably, supported on each of the at least two upright members. Furthermore, the brace also includes a pair of arcuate telescopic arms that are independently, and slidably, supported within the arcuate tube member.

[0020] According to a further aspect of the present disclosure, distally located ends of the at least two upright members and the pair of arcuate telescopic arms are adapted to be secured to at least one of a ceiling and corresponding ones of the sidewalls of the access tunnel, or the brow, upon adjusting one or more of an inclination of the arcuate tube member in relation to the at least two upright members and a length of each telescopic arm relative to the arcuate tube member. [0021] According to a further aspect of the present disclosure, the brace further includes at least two slidable clamps to correspond, in number, with the at least two upright members. The at least two slidable clamps are configured to adjustably, and independently, couple the arcuate tube member to corresponding ones of the at least two upright members.

[0022] According to a further aspect of the present disclosure, each of the at least two slidable clamps includes a front plate, a back plate, and a bolt and nut arrangement to secure the front plate to the back plate for adjustably, and independently, coupling the arcuate tube member to corresponding ones of the at least two upright members.

[0023] According to a further aspect of the present disclosure, a height of each upright member and a distance between successive upright members is user-adjustable.

[0024] According to another aspect of the present disclosure, the brace includes a plurality of arcuate mesh members, each having a top end and a bottom end of a pre- determined width respectively. Further, the brace also includes at least one upright stationary case positioned proximal to the top end of each arcuate mesh member and a telescopic arm slidably disposed within the upright stationary case. A distal end of the telescopic arm is adjustable in relation to the stationary case for facilitating a securement of the corresponding arcuate mesh member with the ceiling of the access tunnel or the brow located adjacent to the stope. Furthermore, the brace also includes at least one clamping element that is provided on a convex side of each arcuate mesh member and located proximal to the bottom end of the corresponding arcuate mesh member. The at least one clamping element is operable for facilitating a securement of the corresponding arcuate mesh member with the uppermost one of the one of the primary grid assembly and the secondary grid assembly, if stacked upon the primary grid assembly.

[0025] According to a further aspect of the present disclosure, each arcuate mesh member has a plurality of upright support ribs successively spaced apart from each other and lengths of successively spaced apart support ribs are one of: equal and unequal to form the top end of the arcuate mesh member in one of: a flattened, inclined, or declined configuration.

[0026] According to a further aspect of the present disclosure, each clamping element includes a threaded rod rotatably engaged with one of the upright support ribs. The threaded rod has a hook member disposed on, and integrally formed with, a portion of a circumference of the threaded rod. Further, the clamping element includes a winged adjustment nut that is rotatably supported on the threaded rod. The adjustment nut is rotatably operable to axially vary a position of the threaded rod relative to the arcuate mesh until the hook member is positioned to secure the corresponding arcuate mesh member with the uppermost one of the one of the primary grid assembly and the secondary grid assembly, if stacked upon the primary grid assembly.

[0027] According to yet another aspect of the present disclosure, a height of each secondary grid assembly is less than a height of the primary grid assembly.

[0028] According to yet another aspect of the present disclosure, before backfilling the stope, a front concave side of the barrier is prepared by selectively applying a hessian to the front concave side of the barrier, and spraying shotcrete over one of the hessian and the front concave side of the barrier.

[0029] According to a further aspect of the present disclosure, at least some portion of, the front concave side of the barrier is configured to define thereon one or more forwardly protruding depth gauges for indicating a depth of the sprayed shotcrete.

[0030] According to yet another aspect of the present disclosure, at least the primary grid assembly of the barrier is foldable from a compact configuration when not in use to an expanded configuration for installation of the bulkhead prior to backfilling.

[0031] According to a further aspect of the present disclosure, a convex rear portion of the barrier further comprises one or more latches to secure the folded configuration of the barrier. [0032] According to yet another aspect of the present disclosure, the base and the barrier are each made from zinc plated mild steel. [0033] Other and further aspects and features of the disclosure will be evident from reading the following detailed description of the embodiments, which are intended to illustrate, not limit, the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS [0034] The illustrated embodiments of the disclosed subject matter will be best understood by reference to the drawings, wherein like parts are designated by like numerals throughout. The following description is intended only by way of example, and simply illustrates certain selected embodiments of devices and processes that are consistent with the disclosed subject matter as claimed herein.

[0035] FIG. 1 is a front view of a bulkhead shown installed within an access tunnel, the bulkhead showing a skid, a primary grid assembly, at least one secondary grid assembly, and a brace of a barrier, and a weighted member that are each supported on the skid, in accordance with an embodiment of the present disclosure;

[0036] FIGs. 2A and 2B are top and side views of the bulkhead from FIG. 1 ;

[0037] FIG. 3A is a top perspective view of the bulkhead showing the skid and the primary grid assembly of the barrier alone, in accordance with an embodiment of the present disclosure; [0038] FIGs. 3B, 3C and 3D are front, side and top views of the bulkhead showing the skid and the primary grid assembly of the barrier from FIG. 3A;

[0039] FIG. 4A is a top perspective view of one secondary grid assembly of the barrier, in accordance with an embodiment of the present disclosure;

[0040] FIGs. 4B, 4C and 4D are front, side and top views of the secondary grid assembly of the barrier from FIG. 4A;

[0041] FIG. 5A is a top perspective view of the brace showing a portion of the brace magnified, in accordance with an embodiment of the present disclosure;

[0042] FIGs. 5B, 5C and 5D are front, side and top views of the brace from FIG. 5A;

[0043] FIG. 6 is a top perspective of the brace shown in another configuration, in accordance with an alternative embodiment of the present disclosure;

[0044] FIG. 7A is a top perspective view of a clamping element employed by the brace of FIG. 6, in accordance with the alternative embodiment of the present disclosure;

[0045] FIGs. 7B, 7C and 7D are side, top, and front views of the clamping element from FIG. 7A; [0046] FIG. 8A is a top perspective view of the skid and the primary grid assembly of the barrier in a folded configuration when not in use;

[0047] FIGs. 8B and 8C are side and top views of the skid and the primary grid assembly from FIG 8 A;

[0048] FIGs. 9A and 9B are top front and bottom rear perspective views of the weighted member, in accordance with an embodiment of the present disclosure;

[0049] FIG. 9C is a top front perspective view of the weighted member showing a bollard supported axially therein, in accordance with an embodiment of the present disclosure; and [0050] FIGs. 9D and 9E are front and top views of the weighted member showing a position of the bollard within the weighted member taken from FIG. 9C.

DETAILED DESCRIPTION

[0051] The following detailed description is made with reference to the figures. Exemplary embodiments are described to illustrate the disclosure, not to limit its scope, which is defined by the claims. Those of ordinary skill in the art will recognize a number of equivalent variations in the description that follows.

[0052] Reference throughout this specification to “an embodiment” or “one embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the disclosed subject matter. Thus, appearances of the phrases “in an embodiment” or “in one embodiment” in various places throughout this specification are not necessarily referring to the same embodiment.

[0053] Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided, to provide a thorough understanding of embodiments of the disclosed subject matter. One skilled in the relevant art will recognize, however, that the disclosed subject matter can be practiced without one or more of the specific details, or with other structures, components, and materials as substitution or replacement to the structures, components, materials disclosed herein. In other instances, one or more structures, components, and materials disclosed herein may altogether be omitted, and equivalent structures, components, materials may be used in lieu thereof. Also, in the present disclosure, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the disclosed subject matter. [0054] FIG. 1 is a front view of a bulkhead 100 shown installed within an access tunnel 102, the bulkhead 100 showing a skid 104, a primary grid assembly 108, at least one secondary grid assembly 110, and a brace 112 of a barrier 106, and a weighted member 114, each of which are supported on the skid 104, in accordance with an embodiment of the present disclosure. FIGs. 2A and 2B are top and side views of the bulkhead 100 from FIG. 1. FIG. 3 A is a top perspective view of the bulkhead 100 showing the skid 104 and the primary grid assembly 108 of the barrier 106 alone, in accordance with an embodiment of the present disclosure while FIGs. 3B, 3C and 3D are front, side and top views of the bulkhead 100 showing the skid 104 and the primary grid assembly 108 of the barrier 106 from FIG. 3 A. Further, FIG. 4A is a top perspective view of one secondary grid assembly 110 of the barrier 106, in accordance with an embodiment of the present disclosure while FIGs. 4B, 4C and 4D are front, side and top views of the secondary grid assembly 110 of the barrier 106 from FIG. 4A. Further, FIG. 5 A is a top perspective view of the brace 112 showing a portion of the brace 112 magnified, in accordance with an embodiment of the present disclosure while FIGs. 5B, 5C and 5D are front, side and top views of the brace 112 from FIG. 5A. FIG. 6 is a top perspective of the brace shown in another configuration, in accordance with an alternative embodiment of the present disclosure. FIG. 7A is a top perspective view of a clamping element employed by the brace of FIG. 6, in accordance with the alternative embodiment of the present disclosure while FIGs. 7B, 7C and 7D are side, top, and front views of the clamping element from FIG. 7A. Furthermore, FIG. 8A is a top perspective view of the skid 104 and the primary grid assembly 108 of the barrier 106 in a folded configuration when not in use while FIGs. 8B and 6C are side and top views of the skid 104 and the primary grid assembly 108 from FIG. 8A. Still further, FIGs. 9A and 9B are top front and bottom rear perspective views of the weighted member 114, in accordance with an embodiment of the present disclosure. Further, FIG. 9C is a top front perspective view of the weighted member 114 showing a bollard 116 supported axially therein, in accordance with an embodiment of the present disclosure while FIGs. 9D and 9E are front and top views of the weighted member 114 showing a position of the bollard 116 within the weighted member 114 taken from FIG. 9C. [0055] Referring to FIG. 1, the bulkhead 100 is shown positioned within the access tunnel 102, or at a brow, for use in facilitating backfilling of a stope (not shown) upon mining thereof. In embodiments herein, it is to be noted that use of the bulkhead 100 is intended at, and for, locations in the access tunnel 102, or the brow, of an underground mine site that are immediately adjacent to, or adjoining, the previously mined stope.

[0056] With continued reference to FIG. 1 and as best shown in the views of 2A-2B, 3A, 3C, 6A and 6B, the bulkhead 100 includes the skid 104. The skid 104 has a base 118 and a pair of post members 120 extending upwardly from the base 118. Preferably, in an embodiment herein, the pair of post members 120 may be configured to extend upwardly from a mid-portion of the base 118 for ensuring maximum stability of the skid 104 and therefore, the overall bulkhead 100. [0057] Further, with continued reference to FIG. 1 and as best shown in the views of FIGs. 3A- 3D, the bulkhead 100 also includes the barrier 106. The primary grid assembly 108 of the barrier 106 is pivotally supported on the pair of post members 120.

[0058] Furthermore, with continued reference to FIG. 1 and as best shown in the views of FIGs. 2B and 4A-4D, the barrier 106 of the bulkhead 100 may also have at least one secondary grid assembly 110 selectively, and sequentially, stacked upon the primary grid assembly 108. For instance, two secondary grid assemblies 110 are shown exemplarily in the views of FIGs. 1 and 2B respectively.

[0059] Still further, with continued reference to FIG. 1 and as best shown in the views of FIGs. 2B and 5A-5D, the brace 112 can be selectively stacked upon an uppermost one of the primary grid assembly 108 and the at least one secondary grid assembly 110. Referring particularly to FIG. 1, it may be noted that in the specific configuration of the barrier 106 shown in the view of FIG. 1, there are two secondary grid assemblies 110 exemplarily stacked upon the primary grid assembly 108 while the brace 112 is stacked upon the uppermost one of the two secondary grid assemblies 110. However, in other embodiments, other configurations of the barrier 106 may be implemented. For instance, the barrier 106 of the present disclosure may include the primary grid assembly 108 while the brace 112 may be directly stacked upon the primary grid assembly 108. In another instance, one or more than two, for example, three, four, or five secondary grid assemblies 110 may be stacked sequentially i.e., one above the other upon the primary grid assembly 108 while the brace 112 may be stacked upon the uppermost one of the one, two, three, four, or five secondary grid assemblies 110 depending on specific requirements of a backfilling application as will be evident upon perusal of the appended disclosure.

[0060] In embodiments herein, an aspect ratio i.e., height and width of the barrier 106, prior to, backfilling, is operably adjustable by individually adjusting one or more of the primary grid assembly 108, the secondary grid assembly 110 and the brace 112 to confirm with an aspect ratio i.e., height and width of the access tunnel 102, or the brow, that is adjacent to the stope for subsequently facilitating backfilling of the stope.

[0061] In an embodiment as shown best in the views of FIGs. 1, 2A-2B, 3A-3D, 8A and 8C, the base 118 of the skid 104 further comprises a pair of legs 122 attached to a bottom portion 124 of the pair of post members 120. Also, the pair of legs 122 may be equi distantly spaced apart from a mid-plane ‘P’ of the skid 104 with a pre-determined distance ‘D’ therebetween. The base 118, and in particular, the pair of legs 122 therein, as shown in the aforementioned views of FIGs. 1, 2A-2B, 3A-3D, 8A and 8C to have a generally square, or rectangular, cross-section to beneficially aid in the lifting of the barrier 106 by a machine, for instance, a forklift using the base 118 of the bulkhead 100. To this end, an amount of the pre-determined distance ‘D’ between each leg 122 of the base 118 and the mid-plane ‘P’ of the overall skid 104 is selected so as to correspond in size with, and therefore facilitate engagement with, a work implement used on the machine, for instance, a pair of tines that are typically used on the forklift.

[0062] Referring to the views of FIGs. 2A-2B, 3A, 3C-3D, 8A and 8C respectively, in an embodiment, the skid 104 further includes a pair of inclined support members 126 angularly extending between, and attached to, a rear portion 128 of the pair of legs 122 and a top portion 130 of the pair of post members 120. The inclined support members 126, disclosed herein, may be additionally, or optionally, provided to impart added strength and improved structural integrity to the bulkhead 100 in withstanding forces that are likely to be encountered during backfilling of the stope.

[0063] Referring now to the views of FIGs. 1, 2A-2B, and 9A-9E respectively, the weighted member 114 may have a pair of holes 132 that may be positioned in alignment with corresponding ones of the pair of legs 122 of the base 118. The weighted member 114 may be slidably, and releasably, engaged, for example, using the work implement of the machine, with a front portion 134 of the pair of legs 122 upon receipt of the pair of legs 122 from the base 118 within the pair of holes 132 that are defined in the weighted member 114. To this end, the holes 132 in the weighted member 114 may also be configured i.e., sized and shaped to mutually correspond with a configuration i.e., a size and shape of the work implement of the machine, for example, the tines of the forklift as well as the configuration i.e., a size and shape of the base 118 and in particular, the pair of legs 122 provided by the base 118. [0064] In a further embodiment, the weighted member 114 may also be further configured to define at least one horizontal passageway 136 therethrough, for example, two horizontal passageways 136 as shown best in the views of FIGs. 9C-9E. In this embodiment, at least one elongated bollard 116, for example, four elongated bollards 116 may be axially disposed within the two horizontal passageways 136 of the weighted member 114 as shown best in the views of FIGs. 9C-9E.

[0065] Turning to FIG. 1, and as best shown in the views of FIGs. 3A-3C, and 8A-8B respectively, the primary grid assembly 108 includes at least one first grid member 138 and at least one second grid member 140 pivotally coupled to corresponding ones of the pair of post members 120 using hinges 142. In the exemplary configuration of the primary grid assembly 108 depicted in the views of FIGs. 1, 3A-3C, and 8A-8B respectively, the primary grid assembly 108 is shown to include three left-handed first grid members 138 and three right-handed second grid members 140. However, the primary grid assembly 108 is not limited to the aforementioned configuration in which three left-handed and three right-handed grid members 138, 140 are used. In other configurations, the primary grid assembly 108 may be configured, during manufacture, to contain equal number of first i.e. right-handed grid members 138 and second i.e., left-handed grid members 140 that are positioned in a side-by side configuration to form the primary grid assembly 108.

[0066] In a further embodiment as shown best in the views of FIGs. 3A and 3B, each of the first and second grid members 138, 140 further include an arcuate stationary rear screen 144 and a correspondingly arcuate front screen 146 that is slidably moveable in relation to the arcuate stationary rear screen 144. Further, each of the front and rear screens 146, 144 has a concave front side and a convex rear side. Additionally, referring to FIGs. 1 and 3A-3B, in a further embodiment, the arcuate front screens 146 of the primary grid assembly 108 has distally located ends 146a that are adapted to be secured with corresponding sidewalls 102a of the access tunnel 102, or the brow, upon slidably moving the front screen 146 in relation to the stationary rear screen 144.

[0067] In a further embodiment, the barrier 106 may further include one or more upright support bars 148, for example, three upright support bars 148 as best shown in the views of FIGs. 3 A, 8A and 8B respectively. These upright support bars 148 may be configured to extend along the convex rear side of the arcuate rear screens 144. Further, top portions 130 of these upright support bars 148 and the pair of post members 120 may be configured define axially upright primary receptacles 150 therein.

[0068] Turning again to FIG. 1, and as best shown in the views of FIGs. 4A-4D, in an embodiment, each secondary grid assembly 110 of the barrier 106 may include a third grid member 152 and a fourth grid member 154 that are pivotally connected to each other. Further, each of the third and fourth grid members 152, 154 may further include locating pins 156 that are configured to depend downwardly to engage with corresponding ones of the axially upright primary receptacles 150 defined in top portions 130 of the post members 120 and the upright support bars 148 (see FIGs. 1, 3A, 8A and 8C respectively) for rendering the at least one secondary grid assembly 110 co-planar with the primary grid assembly 108 when stacked sequentially upon the primary grid assembly 108.

[0069] In a further embodiment as shown best in the views of FIGs. 4A and 4B, each of the third and fourth grid members 152, 154 further include an arcuate stationary rear screen 158 and a correspondingly arcuate front screen 160 that is slidably moveable in relation to the arcuate stationary rear screen 158. Further, each of the front and rear screens 160, 158 has a concave front side and a convex rear side to correspond with the concave front side and the convex rear side of the primary grid assembly 108, or another secondary grid assembly 110, when the secondary grid assembly 110 is stacked above the primary grid assembly 108, or the other secondary grid assembly 110, in a sequential manner as disclosed earlier herein. Furthermore, in an embodiment as best shown in the view of FIG. 1, the slidable front screens 160 of the secondary grid assembly 110 have distally located ends 160a that are adapted to be secured to corresponding sidewalls 102a of the access tunnel 102, or the brow, that are adjacent to the stope upon slidably moving the front screen 160 in relation to the stationary rear screen 158.

[0070] Moreover, with continued reference to the view of FIGs. 1 and 4A-4C in conjunction with the views of FIGs. 3 A and 3D respectively, in an embodiment, the locating pins 156 from each of the third and fourth grid members 152, 154 extend upwardly to define a secondary receptacle 162. In this embodiment, a positioning of the locating pin 156 is selected so as to render the secondary receptacle 162 in alignment with the primary receptacle 150 for facilitating a stacking of another one of the at least one secondary grid assembly 110, for example, a second, third, or fourth secondary grid assembly 110 or the brace 112 itself on the uppermost one of the secondary grid assemblies 110 when more than one secondary grid assembly 110 is used to form the barrier 106 disclosed herein.

[0071] Referring now to FIGs. 1, 2B, and 5A-5D respectively, the brace 112 may include at least two upright members 164, for example, three upright members 164 as shown, that are received axially, and at least partly, within the primary receptacles 150 or the secondary receptacles 162 corresponding to the uppermost one of the primary grid assembly 108 and the secondary grid assembly 110 if, or when, stacked upon the primary grid assembly 108. Further, the brace 112 may also include an arcuate tube member 166 independently, and slidably, supported on each of the at least two upright members 164. Furthermore, the brace 112 may also include a pair of arcuate telescopic arms 168 that are independently, and slidably, supported within the arcuate tube member 166. The independent slidable adjustment in the positioning of each arcuate telescopic arm 168 is configured to facilitate an extension and retraction of the corresponding arcuate telescopic arm 168 in relation to the arcuate tube member 166 for adjusting a length of the corresponding arcuate telescopic arm 168 and therefore, an overall width of the brace 112.

[0072] With continued reference to FIGs. 1, 2B, and 5A-5D respectively, in a further embodiment of this disclosure, distally located ends 164a, 168a of the at least two upright members 164 and the pair of arcuate telescopic arms 168 are adapted to be secured to at least one of a ceiling ‘C’ and corresponding ones of the sidewalls 102a of the access tunnel 102, or the brow, upon adjusting one or more of an inclination of the arcuate tube member 166 in relation to the at least two upright members 164 and the length of each telescopic arm 168 relative to the arcuate tube member 166. The adjustment of the inclination of the arcuate tube member 166 in relation to the at least two upright members 164 and the length of each telescopic arm 168 relative to the arcuate tube member 166 will be explained hereinafter.

[0073] In a further embodiment, the brace 112 may further include at least two slidable clamps 170 to correspond, in number, with the at least two upright members 164, for example, three slidable clamps 170 corresponding to the three upright members 164 as exemp lardy shown in the views of FIGs. 1, 2B, and 5A-5D respectively. The at least two slidable clamps 170 are configured to adjustably, and independently, couple the arcuate tube member 166 to corresponding ones of the at least two upright members 164. [0074] Further, in an embodiment as best shown in the magnified view of the sliding clamp 170 in FIG. 5 A, each of the slidable clamps 170 may include a front plate 172, a back plate 174, and a bolt and nut arrangement 176 that are configured to secure the front plate 172 to the back plate 174 for adjustably, and independently, coupling the arcuate tube member 166 to corresponding ones of the at least two upright members 164. In embodiments herein, a height Ή’ of each upright member 164 and a distance ‘d’ between successive upright members 164 is user-adjustable. Mining personnel may, therefore, easily and quickly adjust the height Ή’ of each upright member 164 and the distance ‘d’ between successive upright members 164, for instance, depending on a height, or curvature, of the ceiling ‘C’ of the access tunnel 102. In the foregoing embodiments, a specific configuration of the brace 112 has been explained for use and implementation in securing the barrier 106 of the bulkhead 100 to the ceiling ‘C’ of the access tunnel 102 (or the brow), in other embodiments such as, for instance, the embodiments pertaining to FIGs. 6 and 7A-7D appended below, other types of structures may be used to form other, or altogether different, configurations of the brace in lieu of that disclosed by way of the foregoing embodiments. Therefore, upon perusal of the appended disclosure, it will be acknowledged by persons skilled in the art that specific configurations of the brace disclosed herein is merely illustrative and explanatory in nature and accordingly, such specific configurations are to be construed as being non-limiting of this disclosure. Rather, persons skilled in the art may readily implement the use of adjustable, partially adjustable, or even non- adjustable configurations of braces for use depending on specific requirements of an application without deviating from the spirit of the present disclosure.

[0075] Referring to the view of FIGs. 6 and 7A-7D respectively, in an alternative embodiment, another configuration of a brace 600 may include a plurality of arcuate mesh members 602, for example, five arcuate mesh members 602a-602e as shown best in the view of FIG. 6. Each arcuate mesh member 602 may be configured to include a top end 604 and a bottom end 606 while each arcuate mesh member is also configured to be of, or have, a pre-determined width ‘M\

[0076] Further, in this alternative embodiment, the brace 600 may also include at least one upright stationary case 608 positioned proximal to the top end 604 of each arcuate mesh member 602 and a telescopic arm 610 slidably disposed within the upright stationary case 608. A distal end 610a of the telescopic arm 610 is adjustable in relation to the stationary case 608 for facilitating a securement of the corresponding arcuate mesh member 602a-602e with the ceiling ‘C’ of the access tunnel 102 (see FIG. 1), or the brow, at a position located adjacent to the stope. [0077] Furthermore, the brace 600 may also be configured to include at least one clamping element 612 that may be provided on a convex side of each arcuate mesh member 602 and located proximal to the bottom end 606 of the corresponding arcuate mesh member 602a-602e. The clamping element 612 is operable for facilitating a securement of the corresponding arcuate mesh member 602a-602e with the uppermost one of the one of the primary grid assembly 108 and the secondary grid assembly 110, if stacked upon the primary grid assembly 108.

[0078] In a further embodiment as best shown in the view of FIG. 6, each arcuate mesh member 602a-602e may have a plurality of upright support ribs 614 successively spaced apart from each other and in which lengths ‘F of successively spaced apart support ribs 614 may be equal or unequal so as to facilitate the formation of the top ends 604 of corresponding ones of the arcuate mesh members 602a-602e in one of a flattened, inclined, or declined configuration.

[0079] For example, as can be seen from FIG. 6, the upright support ribs 614 in each of the arcuate mesh members 602a, 602b, 602d, and 602e are unequal in length and consequently, the top ends 604 formed by the upright support ribs 614 on each of these corresponding arcuate mesh members 602a, 602b, 602d, and 602e have an inclined, or declined, configuration. However, in another example, the upright support ribs 614 of the arcuate mesh member 602c are equal in length and therefore, the top end 604 of the arcuate mesh member 602c has a flattened configuration. It may be noted that one or more of these mesh members 602a-602e may be rearranged in position, replaced with a mesh member of a specific configuration i.e., flattened, inclined, or declined, or omitted altogether from the arrangement to suit, or conform to, a contour, or profile, of the ceiling ‘C’ (see FIG. 1) that is known to dictate, at least in part, an aspect ratio of the overall brow or access tunnel 102, detailed explanation to which will be made later herein.

[0080] Further, with continued reference to the view of FIG. 6 and as shown best in the views of FIGs. 7A-7D, each clamping element 612 may include a threaded rod 702 rotatably engaged with one of the upright support ribs 614. The threaded rod 702 has a hook member 704 disposed on, and integrally formed with, a portion of a circumference ‘C _r ’ of the threaded rod 702. Further, the clamping element 612 may include a winged adjustment nut 706 that is rotatably supported on the threaded rod 702. The adjustment nut 706 may be rotatably operated to axially vary a position of the threaded rod 702 relative to the arcuate mesh member 602 until the hook member 704 is positioned to secure the corresponding arcuate mesh member 602 with the uppermost one of the primary grid assembly 108 and the secondary grid assembly 110, if stacked upon the primary grid assembly 108. For accomplishing securement, the winged adjustment nut 706 is rotated about its axis to impart torque to axially translate the threaded rod 702 and therefore, the hook member 704 on the threaded rod 702 until the hook member 704 engages with a horizontal rib of the uppermost one of the primary grid assembly 108 and the secondary grid assembly 110, if stacked upon the primary grid assembly 108.

[0081] In a further embodiment as shown in the view of FIGs. 1 and 2B respectively, a height Ή2’ of each secondary grid assembly 110 may be less than a height Ή of the primary grid assembly 108. By facilitating a difference in the heights Ή , Ή2’ of respective ones of the primary and secondary grid assemblies 108, 110, mining personnel are beneficially imparted with added flexibility to vary, or increase, a cumulative height [(HI + (n*H2)) where ‘n’ is the number of secondary grid assemblies 110 used in forming the barrier 106] of the primary and secondary grid assemblies 108, 110 and therefore, the overall height of the barrier 106 in nominal, or incremental steps, when stacking one or more secondary grid assemblies 110 onto the primary grid assembly 108 so that distal ends 164a, 168a of the brace 112 can abut with the ceiling ‘C’ and/or the sidewalls 102a of the access tunnel 102. This flexibility in adjustment to the cumulative height [HI + (n*H2)] of the primary and secondary grid assemblies 108, 110, and, therefore, the overall height [(HI + (n*H2) + (x*H)] of the barrier 106 is in addition to, and inclusive of, the adjustments (‘x’), or final adjustments (‘x’), that can be made by the mining personnel to the height Ή’ of each upright member 164 of the brace 112 that can again be easily accomplished by slidably adjusting a position of each upright member 164 relative to the uppermost one of the secondary grid assemblies 110, or the primary grid assembly 108 when the secondary grid assembly 110 is omitted from use, to allow for the distal ends of the brace 112 to abut with the ceiling ‘C’ of the access tunnel 102, or the brow, that is located adjacent to the stope.

[0082] In embodiments herein, before backfilling the stope, the front concave side of the barrier 106 may be prepared by selectively applying a hessian (not shown), that is commonly known to be made of jute, or another similar, or dissimilar, fiber, to the concave front side of the barrier 106. Thereafter, the barrier 106 may be further prepared by spraying shotcrete, a liquid form of concrete that is flowable under pneumatic pressure, over one of the hessian and the concave front side of the barrier 106. To this end, in a further embodiment of this disclosure as shown best in the views of FIGs. 2A-2B, 3A-3D, 4A-4D, 5A and 5C-5D respectively, at least some portion of, the front concave side of the barrier 106 is configured to define thereon one or more forwardly protruding depth gauges 178 for indicating a depth of the sprayed shotcrete to the mining personnel.

[0083] Further, in the views of FIGs. 3A-3D, the primary grid assembly 108 is shown in an expanded configuration for facilitating installation of the bulkhead 100 while in the view of FIGs. 8A-8D respectively, the primary grid assembly 108 is shown in a compacted configuration obtained from folding of the primary grid assembly 108 about the pair of post members 120. Accordingly, in an embodiment herein, at least the primary grid assembly 108 of the barrier 106 is foldable from the compact configuration, for example, when not in use by using the pivotal movement of the first and second grid members 138, 140 about the hinges 142 on corresponding ones of the post members 120 to the expanded configuration for facilitating the installation of the bulkhead 100 i.e., prior to backfilling the stope. Referring to FIGs. 2A-2B, 3A, 3C-3D, and 8A- 8C, in a further embodiment, the convex rear portion 128 of the barrier 106 may further include one or more latches 180, for example, two latches 180 that may be operable i.e., by the user operatively moving the first and second grid members 138, 140 of the primary grid assembly 108, and therefore, the pair of latches 180, to securely position the expanded configuration of the primary grid assembly 108 of the barrier 106 (see FIG. 3 A). Accordingly, in embodiments herein, upon expanding the foldable first and second grid members 138, 140 of the primary grid assembly 108 i.e., prior to accomplishing an installation of the bulkhead 100 within the access tunnel 102, the latches 180 may be configured to latch onto a cross-bar 182, or another equivalent structure, that may be provided at the mid-portion of the base 118, in this case, between the pair of legs 122 of the base 118 as shown best in the view of FIG. 3D.

[0084] In an embodiment herein, the base 118 and the barrier 106 may, each, be made from zinc plated mild steel. Although mild steel with zinc plating thereon has been disclosed herein, such a selection of material is merely explanatory in nature and hence, non-limiting of this disclosure. In alternative embodiments, other materials may be used in place of, or in lieu of, the zinc plated mild steel disclosed herein depending on specific requirements of an application including, but not limited to, a desired amount of weight to be imparted to each of the base 118 and the barrier 106, a desired amount of strength and structural integrity to be imparted to each of the base 118 and the barrier 106, a cost-to- weight analysis computed beforehand for each of the base 118 and the barrier 106, availability of materials at a mine support and/or preparation facility, and so on. Therefore, a specific type of material used for forming respective ones of the base 118 and the barrier 106 are merely illustrative in nature and persons skilled in the art can readily implement a selection of other types of materials to form respective ones of the base 118 and the barrier 106 without deviating from the spirit of the present disclosure.

[0085] In embodiments herein, each of the primary grid assembly 108, the secondary grid assembly 110 and the brace 112 are individually adjustable so that distal ends of each of the primary grid assembly 108, the secondary grid assembly 110 and the brace 112 can abut with corresponding ones of the sidewalls 102a and/or the ceiling ‘C’ of the access tunnel 102 for securement therewith. It is hereby envisioned that owing to irregularities in a surface of the access tunnel 102 or the brow, the sidewalls 102a and and/or the ceiling ‘C’ of the access tunnel 102 or the brow may exhibit uneven, or non-uniformly contoured surfaces that subsequently render the access tunnel 102, or the brow, with an irregular polygonal cross-section and whose dynamically varying aspect ratio can be fully complied with by the use of the bulkhead 100 disclosed herein. Therefore, with implementation and use of the embodiments disclosed herein, the present disclosure advantageously provides mining personnel with infinite, or limitless, possibilities for varying the aspect ratio of the barrier 106 so that the dynamically varied aspect ratio of the barrier 106 i.e., different widths at different heights, for example, Wl, W2, and W3 at respective ones of HI, (H1+(2*H2)), and (H1+(2*H2)+H) of the barrier 106 as shown in FIG. 1, that confirms to the dynamically changing aspect ratios of the access tunnel 102, or the brow, in which the bulkhead 100 is intended for use i.e., when the bulkhead 100 is installed for facilitating backfilling of the stope.

[0086] Further, it is hereby envisioned that as the bulkhead 100 can be installed in the access tunnel 102, or the brow, immediately adjacent to the leading edge of the stope, the bulkhead 100 of the present disclosure obviates the need for extraneous backfilling material that was previously used in conjunction with conventional practices of stope mining. Such elimination, or mitigation, of the extraneous backfilling material may further help mining personnel/company eliminate significant amounts of waste, in terms of time, materials, and costs that was previously encountered with use of the extraneous backfilling material as such backfilling material was, in conventional practice, prepared and poured into the stope and at least some portion of the access tunnel 102, or the brow, adjacent to the stope only to be blasted again upon hardening and to, further, be carried away to another location resulting in the significant amounts of waste. As the bulkhead 100 of the present disclosure can be installed fairly easily and quickly when compared to implementation of conventional practices, use of the bulkhead 100 disclosed herein can help mining personnel/company save valuable time, costs, and effort that are now minimally entailed for the performance of backfilling operations while concomitantly resulting in an improved process performance of the overall mining operations and allowing for realization of improved profitability and revenue from such mining operations.

[0087] It will be appreciated that features of the present disclosure are susceptible to being combined in various combinations without departing from the scope of the present disclosure as defined by the appended claims. Also, various presently unforeseen or unanticipated alternatives, modifications, variations, or improvements therein may be subsequently made by those skilled in the art, which are also intended to be encompassed by the following claims.

[0088] The above description does not provide specific details of manufacture or design of the various components. Those of skill in the art are familiar with such details, and unless departures from those techniques are set out, techniques, known, related art or later developed designs and materials should be employed. Those in the art are capable of choosing suitable manufacturing and design details. The terminology used herein is for the purpose of describing.