MINING APPARATUS AND METHODS

RELATED APPLICATIONS

[0001] This claims priority from United States provisional patent application no. 63/077,659 filed September 13, 2020, the entire contents of which are incorporated herein by reference.

FIELD

[0002] This relates to mining, in particular, to methods and apparatus for underground excavation, development and extraction.

BACKGROUND

[0003] Mining of underground deposits such as ore bodies requires excavation of very large quantities of material and transportation of such material to or toward the surface for processing. Handling of such materials requires heavy equipment, such as blasting or drilling equipment, material handling equipment, structural components, and the like. Some or all of such heavy equipment must be transported throughout the mine structure.

[0004] Typically, equipment, personnel and rock are moved using wheeled vehicles. Unfortunately, this technique has numerous deficiencies. For example, the inclination of mine tunnels is limited by the maximum incline on which wheeled vehicles can be safely operated. As a result, some formations cannot be mined in an economically viable manner using conventional methods.

[0005] In addition, the minimum dimensions of tunnels are defined by the space requirements for operation of vehicles. Moreover, movement of material by vehicles is inefficient and limits the rate at which material can be removed and processed.

[0006] Vehicles used in mines are commonly driven by internal combustion engines. Use of such engines underground poses problems. For example, mines must be effectively ventilated to remove internal combustion engine exhaust. Ventilation is very costly and insufficient ventilation can lead to unsafe air quality in the mine. SUMMARY

[0007]An example system for mining material in an underground tunnel comprises: at least one rail mounted to a roof of the tunnel; a box releasably suspended from the rail using hoists and movable along the rail, wherein the hoists are selectively operable to: lower the box onto a floor of the tunnel for loading of material through an open end of the box; raise the box toward the rail for movement along the rail; and tilt the box to a discharge angle for allowing loaded material to fall from the box.

[0008] In some embodiments, the system comprises an outhaul boom mounted to the rail and extending from the box toward an end face of the tunnel.

[0009] In some embodiments, the outhaul boom is pivotable relative to the rail.

[0010] In some embodiments, the system comprises a blade suspended from the outhaul boom, wherein the blade is movable through a stroke to pull the material into an open end of the box.

[0011] In some embodiments, the blade is suspended on a wire running to the outhaul boom.

[0012] In some embodiments, the system comprises a plurality of parallel rails, each having a box releasably suspended therefrom and a plurality of outhaul booms, each mounted to one of the plurality of rails and extending toward the end face of the tunnel.

[0013] In some embodiments, the system comprises a plurality of blades, each suspended on a wire running to a respective outhaul boom and each movable through a stroke to pull the material into a box suspended from a respective one of the plurality of rails.

[0014] In some embodiments, the system comprises a drag drum positioned between the rails, the drag drum operable to move each of the blades through its stroke by retraction of its wire. [0015] In some embodiments, the system comprises a transfer chute positioned below the rail such that the transfer chute discharges onto a conveyor, wherein a box is movable along the rail into a position above the transfer chute, to transfer material to the transfer chute by tilting of the box.

[0016] In some embodiments, the transfer chute is operable to regulate a rate of discharge onto the conveyor.

[0017] Example embodiments may include the foregoing features in combination.

[0018] An example method for transporting material in an underground mine tunnel, comprises: receiving the material in a box suspended from a rail mounted to a roof of the tunnel; raising the box toward the rail using hoists mounted to the rail; moving the box along the rail; tilting the box using the hoists to discharge the material.

[0019] In some embodiments, the method comprises moving a blade through a stroke between the box and a boom mounted to the rail, to pull the material into the box.

[0020] In some embodiments, the method comprises pivoting the boom relative to the rail.

[0021] In some embodiments, moving a blade through a stroke comprises winding a wire around a drum.

[0022] In some embodiments, the rail is a first rail, the box is a first box and the blade is a first blade, and the method comprises moving a second blade through a stroke to pull material into a second box suspended from a second rail mounted to the roof of the tunnel.

[0023] In some embodiments, moving the first blade through a stroke and moving the second blade through a stroke comprises winding a wire around a drag drum.

[0024] In some embodiments, the drag drum is positioned between the first rail and the second rail. [0025] In some embodiments, the method comprises tilting the box to transfer the material into a transfer chute positioned below the rail, and discharging the material from the transfer chute onto a conveyor.

[0026] In some embodiments, the method comprises regulating a rate of discharge of material from the transfer chute onto the conveyor.

[0027] Example embodiments may include the foregoing features in combination.

[0028] An example system for transporting material in an underground mine tunnel, comprises: at least one rail mounted to a roof of the tunnel; a frame suspended from the rail and movable along the rail; box releasably coupled to the frame; a plurality of hoists operable to raise and lower the frame, to move the box between a loading position on a floor of the tunned; a transport position proximate the rail, and a discharge position in which the box is tilted.

[0029] In some embodiments, the system comprises a boom mounted to the rail and positioned between the box and an end face of the tunnel, for moving a blade between the box and the boom to pull material into the box.

[0030] Other embodiments will be apparent based on the detailed description.

BRIEF DESCRIPTION OF DRAWINGS

[0031] In the figures, which depict example embodiments:

[0032] FIG. 1 is a schematic of a mine;

[0033] FIG. 2 is an isometric view showing a rail, conveyor tram and loading apparatus in a tunnel;

[0034] FIG. 3 is an enlarged isometric view of a carriage on the rail of FIG. 2;

[0035] FIG. 4 is a simplified cross-section view of a conveyor belt and rollers;

[0036] FIG. 5 is an isometric view of two conveyor trams on respective rails; [0037] FIG. 6 is an isometric view of a crossover mechanism between the rails of FIG. 5;

[0038] FIGS. 7A, 7B, 70 are schematic views showing an alternate crossover mechanism;

[0039] FIG. 8 is an isometric view of a drilling apparatus on the rail of FIG. 2;

[0040] FIGS. 9A-9B are isometric views showing operational configurations of the drilling apparatus of FIG. 8;

[0041] FIG. 10 is a side view of the drilling apparatus of FIG. 8 in a transport configuration;

[0042] FIG. 11 is an isometric view of a platform apparatus and explosive transportation unit on the rail of FIG. 2;

[0043] FIG. 12 is an isometric view of the platform apparatus of FIG. 11 in a transport configuration;

[0044] FIG. 13 is an isometric view of a stabilizer;

[0045] FIG. 14 is a flow chart depicting a process of mining in a tunnel;

[0046] FIG. 15 is an isometric view showing a junction of a tunnel and a main tunnel of the mine of FIG.1 ;

[0047] FIG. 16 is an isometric view of a conveyor in the main tunnel of FIG. 15, with an enlarged view of a joint between conveyor belt sections;

[0048] FIG. 17 is a schematic view showing relative positions of a loading device, conveyor tram and conveyor within the main tunnel of FIG. 15;

[0049] FIGS. 18A-18B are schematic diagrams of another conveyor tram and a conveyor within the main tunnel of FIG. 15;

[0050] FIG. 180 is a schematic diagram of a belt of the conveyor of FIGS. 18A-18B; [0051] FIG. 19 is a flow chart depicting a process of mining in a main tunnel;

[0052] FIG. 20 is a flow chart depicting a process of stope mining between tunnels;

[0053] FIG 21 is a schematic view showing a block between overcut and undercut tunnels;

[0054] FIG. 22 is an isometric view showing blasting of the block of FIG. 21 ;

[0055] FIG. 23 is an isometric view showing excavation of a debris pile and a stope;

[0056] FIG. 24 is an isometric view showing excavation of a debris pile and a stope;

[0057] FIG. 25 is an isometric view showing excavation of a debris pile and a stope;

[0058] FIG. 26A is an isometric view of a muck box system;

[0059] FIG. 26B is a partial schematic side view of the system of FIG. 26A;

[0060] FIG. 27 is an isometric view of a muck box of the system of FIGS. 26A and 26B;

[0061] FIG. 28A is an end view of the muck box of FIG. 27;

[0062] FIG. 28B is a side view of the muck box of FIG. 27;

[0063] FIG. 29 is schematic side view of the muck box of FIG. 27 supported on the rail of FIG. 2;

[0064] FIGS. 30A, 30B and 30C are schematic side views depicting the muck box of FIG. 27 supported on the rail of FIG. 2, in lowered, raised and tilted positions, respectively;

[0065] FIG. 31 is an isometric view of a short haul carrier of the system of FIGS. 26A- 26B;

[0066] FIG. 32 is an isometric view of a long haul carrier of the system of FIGS. 26A- 26B; [0067] FIG. 33 is a plan view of a junction between tunnels;

[0068] FIG. 34 is a side cross-sectional view of the junction of FIG. 33; and

[0069] FIG. 35 is a plan view of another muck box system.

DETAILED DESCRIPTION

[0070] FIG. 1 shows a schematic view of an example mine 100. Mine 100 is constructed within a rock formation containing a mineral resource. Herein, the mineral resource body is referred to as an ore body 102. However, the present disclosure is not limited to mining of ore bodies.

[0071] Mine 100 includes a main tunnel 104, which may be inclined, and a plurality of secondary tunnels 106 which branch from main tunnel 104. Main tunnel extends proximate ore body 102. Secondary tunnels 106 extend away from main tunnel 104 and into ore body 102.

[0072] Generally, main tunnel 104 provides a path for machinery, personnel and material to be moved between the surface and working areas in the mine. For example, machinery, personnel and structural material may traverse main tunnel 104 and be used to extend the tunnel 104 or tunnels 106, or to break (e.g. drill or blast) material from ore body 102. Such activities may create fragmented waste rock and ore, referred to as muck, which may be removed to the surface by way of main tunnel 104.

[0073] Tunnels 106 communicate with main tunnel 104 and extend away from main tunnel 104 into ore body 102. Tunnels 106 are constructed to provide access to ore body 102 for extraction of resources.

[0074] Each tunnel 106 ends at a rock face 109. Excavation may be performed in cycles. That is, drilling or blasting may be performed at face 109 to break rock for removal. The resulting fragments, referred to as muck, may be removed, and then drilling or blasting may be repeated. Each repetition of this cycle adds a specific depth to tunnel 106. [0075] Each of main tunnel 104 and secondary tunnels 106 may be a straight linear corridor or may contain one or more curves. The radius of curves in a particular tunnel are subject to performance limitations of the apparatus used for transportation in that tunnel.

[0076] Junction section 112 is a portion of tunnel 106 proximate to main tunnel 104. Junction section 112 includes features for permitting transfer of material and apparatus between tunnel 104 and tunnel 106.

[0077] FIG. 2 is a perspective view showing example equipment in a tunnel 106.

[0078] Tunnel 106 is bounded by top and bottom surfaces, referred to respectively as the roof 114 and floor 116, and lateral surfaces referred to as side walls 118.

[0079] Tunnel 106 contains a transport system. As shown, the transport system includes a rail 120 suspended from roof 114. Rail 120 is secured to roof 114 using a plurality of rock bolts spaced apart along roof 114 of tunnel 106. The size, quantity and spacing of the rock bolts may depend on, for example, the composition of ore body 102 and the surrounding waste rock; the length of tunnel 106; and the amount of weight expected to be borne by the transport system.

[0080] In the depicted embodiment, rail 120 is a monorail. Wheeled carriages 122 may be mounted to monorail 120 for movement along the monorail. Propulsion of carriages 122 along monorail 120 may be achieved using any suitable drive system. For example, some carriages 122 may have an internal drive unit. The drive unit may include an electrical motor which may be provided power by way of a lead integrated with monorail 120 or proximate monorail 120. In some embodiments, the electrical drive may have a wheel to frictionally drive carriage 122 along monorail 120. In other embodiments, the electrical drive may have a geared interface with monorail 120 or with an auxiliary rack. As will be apparent, a geared interface may be capable of exerting greater motive force, and may be suitable for operation at large inclination angles.

[0081] Monorail 120 extends substantially the entire length of tunnel 106, such that carriages 122 on monorail can be moved from a proximal end where monorail and tunnel 106 interface with main tunnel 104, to a distal end where carriages 122 can position equipment for working on rock face 109.

[0082] Referring to FIG. 2, a conveyor tram 130 and a muck loading apparatus 132 are depicted. Both of conveyor tram 130 and muck loading apparatus 132 are supported on monorail 120. Conveyor tram 130 and muck loading apparatus 132 are suspended from a plurality of carriages 122 on monorail 120.

[0083] FIG. 3 depicts an enlarged interface between monorail 120 and a carriage 122. As shown, rail 120 has a generally l-shaped cross section. Carriage 122 includes rollers 123 which interface with rail 120 to lock the carriages. An electric drive 125 is also provided and may be mounted to carriage 122, either directly or by way of a frame.

[0084] Rail 120 has an underside with a series of projecting teeth 127 defining a gear rack. Drive 125 has an output gear (not shown) with teeth configured to mesh with teeth 127. Alternatively, rail 120 may lack teeth 127, in which case drive 125 may interface fictionally with rail 120. In frictional-interface embodiments, rail 120 may optionally comprise a friction-increasing surface to increase traction for drive 125.

[0085] Although FIG. 3 depicts a drive 125 which engages directly with rail 120, in some embodiments, the drive engagement may be with an auxiliary rail positioned proximate rail 120.

[0086] Conveyor tram 130 has a frame 134. In the depicted embodiment, conveyor tram also has a chassis 136 mounted to carriages 122 proximate monorail 120 and between frame 134 and carriages 122. Chassis 136 houses a drive 139 operable to propel conveyor tram along monorail 120 as a unit. The drive may comprise an electrical motor and may have a frictional or geared drive interface.

[0087] A conveyor 138 is carried on frame 134. As shown, conveyor 138 is an endless belt conveyor. In the depicted embodiment, conveyor 138 has a belt 140 formed of metallic (e.g. steel) core links, covered with a polymer (e.g. rubber) layer. Alternatively, belt 140 may be constructed of woven fabric or entirely of a polymer such as rubber. [0088] Belt 140 is carried on a plurality of rollers, including one or more drive rollers 142 and one or more idler rollers 144. Drive rollers 142 are driven by an electric motor (not shown). The electric motor may be powered by an electrical lead integrated with or proximate to monorail 120.

[0089] As will be described in further detail, conveyor tram 130 is operable to receive a load of fragmented waste rock or resource material for removal from tunnel 106 to main tunnel 104 and subsequently, to the surface.

[0090] Conveyor tram 130 has two modes of moving material. Specifically, a first mode involves movement of the conveyor tram 130 along monorail 120. A drive acting between conveyor tram 130 and a support, such as monorail 120, is used to propel the conveyor tram towards or away from face 109. Conveyor tram 130 moves away from face 109 to unload material and towards face 109 to return for reloading.

[0091] In a second mode, belt 140 of the conveyor tram is moved by drive rollers 142. Belt 140 can be moved while the conveyor tram 130 itself moves along monorail 120. Alternatively, belt 140 can be moved while conveyor tram 130 is static.

[0092] Advancing belt 140 moves material relative to frame 134 and enables fragmented material to be loaded along the length of belt 140 from a fixed loading point. For example, material may be loaded onto conveyor tram 130 at an end close to the tunnel face 109, referred to herein as the distal end. As such loading occurs, continued movement of belt 140 moves the loaded material towards the opposite end, i.e. the end closest to main tunnel 104, referred to herein as the proximal end.

[0093] Likewise, material may be unloaded from conveyor tram 130 at a location near its proximal end. Advancing belt 140 moves loaded material from the distal end towards the proximal end for unloading.

[0094] FIG. 4 is a simplified cross sectional view of an example configuration of belt 140 and idler rollers 144 supporting belt 140. As depicted, rollers 144 are arranged generally in an arch, and belt 140 lies atop the arch defined by rollers 144. Fragmented material deposited onto belt 140 collects on the inside of the arch. This configuration tends to be relatively space-efficient. That is, the cross-sectional area of the material pile that forms on belt 140 is large relative to the width of the belt.

[0095] Other cross-sectional arrangements are possible, as will be apparent. For example, rollers 144 may support belt 140 in a horizontal plane or in a trough shape, with a planar bottom and angled sides.

[0096] Referring again to FIG. 2, muck loading apparatus 132 is operable to move fragmented rock, referred to as “muck”, away from face 109 and floor 116 and onto conveyor tram 130.

[0097] Like conveyor tram 130, muck loading apparatus 132 is suspended from monorail 120. Specifically, a frame 150 of the muck loading apparatus is suspended on carriages 122. A drive unit 152 is positioned in frame 150 and operable to propel muck loading apparatus 132 along monorail 120 towards and away from face 109. In the depicted embodiment, drive unit 152 comprises an electric motor, powered by a supply lead integrated with or positioned proximate monorail 120. Drive motor 152 may have a frictional or geared drive interface.

[0098] Frame 150 supports a ramp unit 154, a discharge unit 158 and an outrigger unit 156.

[0099] Ramp unit 154 has a distal end positioned nearest face 109 and a proximal end, positioned nearest main tunnel 104. Ramp unit 154 is supported near its proximal end by frame 150. Ramp 154 is pivotable relative to frame 150 about a horizontal axis, such that the distal end of ramp unit 154 can be pivoted toward roof 114 or toward floor 116. Ramp 154 is also pivotable relative to frame 150 about a vertical axis, such that it can be angled towards one or the other of side walls 118. As will be described in greater detail, ramp unit 154 is movable between stowed and operational positions. FIG. 2 depicts ramp unit 154 in its operational position.

[0100]As shown, the distal end of ramp unit 154 is positioned near floor 116 and ramp unit 154 is angled upwardly so that its proximal end is positioned slightly above and near the distal end of conveyor tram 130. [0101] Ramp unit 154 has a conveyor 160. Conveyor 160 may be an electric motor- driven endless belt conveyor, substantially similar to conveyor 138 of conveyor tram 130. Conveyor 160 may be driven at variable speed and is operable to move muck from the conveyor’s distal end towards its proximal end, for loading onto conveyor tram 130 by way of discharge unit 158.

[0102] Outrigger unit 156 of the muck loading apparatus has a boom 162 mounted to and extending distally of frame 150. As depicted, frame 150 may be positioned near the end of monorail 120, such that boom 162 of outrigger unit 156 extends beyond monorail 120. Boom 162 is sufficiently long to span a distance between the end of monorail 120 and face 109 of tunnel 106. That distance corresponds to a minimum distance at which machinery must positioned relative to a blasted rock face for equipment operation and recovery of blasted material. In the depicted embodiment, the distance is 3 metres. However, the distance may be larger or smaller.

[0103] Boom 162 is supported near its proximal end by frame 150. Boom 162 is pivotable relative to frame 150 about a vertical axis, such that it can be angled towards one or the other of side walls 118 of the tunnel. Boom 162 may also be pivotable about a horizontal axis, such that the distal end of boom 162 can be pivoted toward roof 114 or toward floor 116 of the tunnel. Boom 162 may also be axially extendable towards or away from face 109.

[0104] Boom 162 supports a pulley 164 at the boom’s distal end. A pulley wire 165 is looped in a circuit around pulley 164, a second pulley 166 at the distal end of ramp unit 154, and a third pulley 168 at the proximal end of ramp unit 154.

[0105]A blade 170 is mounted to pulley wire 165. Blade 170 can be reciprocated by movement of wire 165 through a stroke between pulley 164 at the distal end of boom 162 and second pulley 166 at the distal end of ramp unit 154.

[0106] Blade 170 rests atop a muck pile 172 produced by breaking (e.g. drilling and blasting) of face 109. Pulling of blade 170 through its stroke towards ramp unit 154 pulls fragmented rock onto conveyor 160 of the ramp unit. [0107] At the proximal end of conveyor 160, fragmented rock falls from conveyor 160 to discharge unit 158. Discharge unit 158 comprises a chute (not shown) for directing the rock onto conveyor 138 of conveyor tram 130.

[0108] It is desirable for rock to be evenly distributed along conveyor 138 of conveyor tram 130. Even distribution avoids concentration of loads on the conveyor. To this end, discharge of rock from ramp unit 154 to conveyor tram 130 may be metered.

[0109] In some embodiments, metering is achieved by adjusting speeds of conveyor 160 and conveyor 138. For example, conveyor 138 and conveyor 160 may be held at substantially identical linear speeds so that rock does not accumulate on conveyor 160. Alternatively, conveyors 138 and 160 may be held at linear speeds in a constant ratio to one another, such that accumulation of rock is consistent.

[0110] In some embodiments, discharge unit 158 may be equipped with a discrete metering device. For example, discharge may be metered through an orifice to limit the flow rate of fragmented rock onto conveyor 138. Additionally or alternatively, a measurement device such as a metering wheel, a machine vision system, or a conveyor load cell could be used to measure the quantity of rock discharged onto conveyor 138.

[0111] In some embodiments, multiple rails 120 may be provided within tunnel 106. For example, FIG. 5 depicts a system including two rails 120 (individually, 120-1 , 120-2) extending parallel to one another.

[0112] Rails 120-1 , 120-2 may be coextensive. That is, both rails 120-1 , 120-2 may extend from a junction with main tunnel 104 to distal ends of tunnel 106 at substantially identical distances from face 109. Each rail 120 is capable of supporting apparatus such as conveyor tram 130 or muck loading apparatus 132. As depicted, rails 120-1 , 120-2 respectively support conveyor trams 130-1 , 130-2.

[0113] Rails 120-1 , 120-2 provide flexibility for performing multiple operations within tunnel 106. For example, as shown in FIG. 2, muck loading device 132 and conveyor tram 130 are arranged serially as a pair on a rail 120-1. Additional apparatus, such as a second pair of a muck loading device and conveyor tram, could be supported on a second rail 120-2. Alternatively, other apparatus such as blasting apparatus or a working platform for supporting workers could be provided.

[0114] Rails 120-1 , 120-2 also provide flexibility of movement within tunnel 106. Specifically, one piece of apparatus could move in the distal direction of tunnel 106 along rail 120-1 . A second piece of apparatus could move in the proximal direction of tunnel 106 along rail 120-2. Such pieces of apparatus could pass one another while moving in opposite directions.

[0115] In some embodiments, a crossover mechanism may be provided between multiple rails 120. For example, FIG. 6 depicts a crossover mechanism 174 that permits carriages 122 to cross from rail 120-1 to rail 120-2. Crossover mechanism 174 may be located anywhere along the length of tunnel 106, subject to spatial constraints. In some embodiments, multiple crossover mechanisms may be present at different points along the length of tunnel 106, allowing carnages 122 to change tracks at multiple locations.

[0116] FIGS. 7A-7C depict another crossover mechanism, in which carriages 122 are pivotably and releasably attached to the frame supported thereon. The crossover mechanism includes a frame member 129 which could be part of a frame of any apparatus disclosed herein, and which is connected to a first carriage 122-1 at a distal end and to a second carriage 122-2 at a proximal end. Connections between carriages 122 and frame member 129 are releasable and are pivotable, such that when the connection at one end is released, the free end may be pivoted around the connected end.

[0117] Carriages 122-1 , 122-2 are mounted to a first rail 120-1. Additional carriages 122-3, 122-4 are mounted to a second rail 120-2. As shown in FIG. 7B, the connection between carriage 122-2 and frame member 129 is released. The proximal end of frame member 129 is then pivoted about carriage 122-1 to align and connect frame member 129 with carriage 122-4. [0118]As shown in FIG. 7C, the connection between frame member 129 and carriage 122-1 is released and then the frame member is pivoted around carriage 122-4 to align and connect frame member 129 with carriage 122-3.

[0119] Thus, after the two pivots, frame member 129 moves from being carried on rail 120-1 to being carried on rail 120-2.

[0120] In some examples, the releasable connections between frame member 129 and carriages 122 may be locked and released by manual insertion or removal of pins.

[0121] In addition to conveyor tram 130 and muck loading apparatus 132, other types of apparatus may be supported on rails 120.

[0122] FIG. 8 depicts an example drilling apparatus 200 that may be supported on rails 120 and transported along the length of tunnel 106 on rails 120.

[0123] Drilling apparatus 200 is operable to drill holes in any of roof 114, floor 116, walls 118 and face 109 of tunnel 106. Such holes may, for example, be for securing ground support hardware or for inserting explosives for blasting.

[0124] Drilling apparatus 200 has a frame 202 supported by a plurality of carriages 122 on rail 120. Drilling apparatus 200 also includes a drive unit 125 operable to propel drilling apparatus 200 along the length of rail 120. The drive unit 125 may drive apparatus 200 fictionally or using a geared interface.

[0125] A boom 206 extends from frame 202 toward face 109. As previously noted, the distal end of rail 120 is typically spaced apart from face 109 by a distance corresponding to the minimum safe distance from a blast event. Boom 206 is sufficiently long to reach across such spacing so that the end of boom 206 can perform operations on face 109.

[0126] Boom 206 comprises a support link 210 and a tool holder 212. Support link 210 is connected to frame 202 by way of a joint 214. Support link 210 is pivotable relative to frame 202 around joint 214. Joint 214 permits rotation of support link 210 at least in a horizontal plane. Support link 210 can also be axially extended or retracted, e.g. by an electrical, hydraulic or pneumatic actuator.

[0127]Tool holder 212 is connected to support link 210 by way of a pivotable joint 216. Joint 216 permits tool holder 212 to rotate in at least two axes relative to support link 210. Specifically, tool holder 212 can be rotated in a horizontal plane parallel to that in which joint 216 can be rotated, and in a second, orthogonal direction around a horizontal axis parallel to the support link 210. Drilling apparatus 200 is therefore able to reach a large portion of face 109 and the surrounding roof 114, floor 116 and walls 118 of tunnel 106.

[0128] Movement of boom 206 around joints 214, 216 may be effected by actuators, which may for example be electrically operated actuators, such as servomotors, or hydraulic or pneumatic pistons. Other suitable actuators are possible, as will be apparent to skilled persons.

[0129]Tool holder 212 is mounted to the distal end of support link 210 at approximately the midpoint of tool holder 212 and may be pivoted so that either end of the tool holder can be positioned to face any of roof 114, floor 116, walls 118 or face 109. Tools may be mounted at both ends of tool holder 212. In the depicted embodiment, the tools are electrically operated drills with bits suitable for drilling in rock. The bits may be removable, such that they can be easily replaced or exchanged with other bits suited to the composition of rock surrounding tunnel 106.

[0130] Drilling apparatus 200 is operable in a first mode, depicted in FIG. 8, for drilling structural support holes in walls 118 of tunnel 106. That is, as shown in FIG. 8, tool holder 212 is positioned in a horizontal orientation, with each drill facing one of walls 118. The drills may be operated to bore holes into the rock for receiving rock bolts.

[0131] Support link 210 may be moved around joint 214 to reposition the drills relative to walls 118. Thus, by articulation of boom 206, holes may be drilled in walls 218 in substantially any desired pattern. [0132] In a second mode, depicted in FIG. 9A, tool holder 212 can be pivoted into a vertical position. In the vertical position, a drill carried on tool holder 212 faces roof 114. The drill can then bore holes in roof 114 for receiving rock bolts to anchor tunnel support structure and tracks 120. By extension of support link 210 and pivoting around joints 214, 216, tool holder 212 can be moved to drill holes in roof 114 in substantially any desired pattern.

[0133] In a third mode, depicted in FIG. 9B, tool holder 212 can be pivoted into a horizontal position, substantially perpendicular to face 109. In this position, a drill carried on tool holder 212 faces face 109. The drill can then bore holes in face 109 for receiving blast charges. By extension of support link 210 and pivoting around joints 214, 216, tool holder 212 can be moved to drill holes in face 109 in substantially any desired pattern.

[0134] Drilling apparatus 200 can also be operated in a transport mode, depicted in FIG. 10. In the transport mode, support link 210 and tool holder 212 are folded under frame 202. In the transport mode, drilling apparatus 200 is physically compact, and the center of mass of drilling apparatus 200 is relatively close to tracks 120. Accordingly, the apparatus is relatively stable for transportation and is less likely to interfere with other apparatus as it is moved.

[0135] FIG. 11 depicts an example platform apparatus 220 that can be supported on a track 120. Platform apparatus 220 has a frame 222 supported on track 120 by way of a plurality of carriages 122. A drive unit 223 is mounted to frame 222. The drive unit may, for example, include a variable speed electric motor operable to drive platform apparatus along rail 120 by a frictional or geared interface. A working platform 224 is supported on frame 202 by way of a multi-bar linkage 226. Linkage 226 has pivotable joints 228 connecting the linkage 226 to frame 202 and pivotable joints 230 connecting the linkage 226 to platform 224. Linkage 226 may also be axially extendable and retractable, e.g. by way of electrical, hydraulic or pneumatic actuators. Thus, linkage 226 permits movement of platform 224 in multiple axes. [0136] Platform 224 is operable to support workers or apparatus for working on any of roof 114, floor 116, side walls 118 and face 109. For example, platform 224 may be used to elevate workers to install support structure to roof 114, or to insert explosive charges in face 109. Other applications are possible, as will be apparent. Platform 224 has guard rails 225 for protecting against falls by workers. Guard rails 225 are pivotably attached to platform 224, such that the guard rails can be selectively fixed in an upright position, e.g. using pins, or collapsed to lie flat against platform 224.

[0137] Linkage 226 is configured so that platform 224 can be held in a horizontal orientation in a wide range of possible locations. Specifically, axial extension or retraction of linkage 226 and articulation of linkage 226 around joints 228, 230 may allow platform 224 to be held in a horizontal position while providing access to any portion of roof 114 between the ends of tracks 120 and face 109, or to any portion of face 109.

[0138] An explosives transportation unit 232 may also be supported on tracks 120. The explosives transportation unit 232 may be integrally formed with platform apparatus 220 and supported on frame 222. Alternatively, explosives transportation unit 232 may have a separate frame and be supported on separate carriages 122, and moved into proximity with platform apparatus 220.

[0139] As depicted, explosives transportation unit 232 is equipped with tooling for workers to transfer explosive charges into holes bored in face 109 using drilling apparatus 200. In the depicted embodiment, the tooling comprises nozzles for injecting explosive material in a flowable form, e.g. a slurry. However, other tooling is possible, for transferring explosives in different forms. The tooling may also be capable of inserting ignition devices, e.g. wires for electrical ignition, which may be operated remotely.

[0140] Platform apparatus 220 is also operable in a transport mode, as shown in FIG. 12. In the transport mode, platform 224 and linkage 226 are extended to raise the platform close to rail 120. In the depicted embodiment, guard rails 225 on the working platform 224 are also folded flat against the platform. [0141]Any apparatus supported from tracks 120, including conveyor tram 130, muck loading apparatus 132, drilling apparatus 200, platform apparatus 220 and explosives transportation unit 232, may be equipped with stabilization devices for stabilizing the apparatus during operation.

[0142] FIG. 13 depicts an example stabilization device 240. As shown, stabilization device 240 is mounted to a frame proximate a carriage 122.

[0143] Stabilization device 240 includes an anchor tip 242 for engagement with roof 114, floor 116, side walls 118 or face 109 of tunnel 106. Anchor tip 242 is mounted on a linear actuator which is extendable to urge anchor tip 242 into contact with roof 114, floor 116, side walls 118 or face 109. The actuator may, for example, comprise a hydraulic or pneumatic cylinder, or an electro-mechanical drive such as a ball screw.

[0144] Anchor tip 242 may be formed of a material of sufficient hardness to dig into roof 114, floor 116, side walls 118 or face 109. For example, the anchor tip may be formed of a suitable tool steel or carbide. Alternatively or additionally, anchor tip 242 may have a high-friction surface for frictional ly engaging roof 114, floor 116, side walls 118 or face 109. Thus, when anchor tip 242 is urged into contact with roof 114, floor 116, side walls 118 or face 109, the anchor tip 242 grips the roof 114, floor 116, side walls 118 or face 109 and braces the frame against relative movement between the frame and the roof 114, floor 116, side walls 118 or face 109.

[0145] Stabilization device 240 has an adjustable base 244. Adjustable base 244 is pivotably mounted to the frame, and has an actuator such as a hydraulic or pneumatic cylinder or servo operable to adjust the orientation of base 244 and of stabilization device 240 relative to the frame. The orientation may be chosen based on the loads expected to be imposed on the frame. For example, stabilization device 240 may be oriented substantially vertically to brace drilling apparatus 200 for drilling in roof 114. Stabilization device may be angled outwardly towards walls 118 to brace against lateral loads, e.g. for drilling in walls 118. Optionally, multiple stabilization devices 240 may be provided on the same piece of equipment, and may be oriented at different angles to provide bracing in multiple directions. [0146] In some embodiments, stabilization devices 240 may be installed to portions of equipment other than frames. For example, instead of or in addition to the respective frames, stabilization devices 240 may be provided on any of outrigger unit 156, ramp unit 154 or discharge unit 158 of muck loading apparatus 132; boom 206 of drilling apparatus 200; or platform 224 of platform apparatus 220.

[0147] FIG. 14 is a flow chart showing an example method 300 of operation in a tunnel 106.

[0148] At box 302, a pile of fragmented rock material, referred to as a muck pile, lies proximate face 109 of tunnel 106. Muck loading apparatus 132 is advanced to the distal end of rail 120 (see FIG. 2), which rail is spaced apart from face 109 by a safety margin corresponding to the minimum safe distance from a blast.

[0149] Outrigger unit 156 is extended over the muck pile so that its distal end is positioned proximate face 109 and roof 114. Blade 170 is drawn towards the distal end of outrigger unit 156 and allowed to rest atop the muck pile.

[0150] Ramp unit 154 is also extended towards the muck pile and its distal end is lowered to rest on floor 116 proximate the muck pile. The conveyor 160 of ramp unit 154 is activated for moving material from its distal end towards its proximal end.

[0151] Discharge unit 158 is positioned to receive material from the proximal end of ramp unit 154 and direct the material onto the distal end conveyor 138 of conveyor tram 130. Conveyor 138 is also activated for moving material from its distal end towards its proximal end.

[0152] Wire 165 is then moved to drag blade 170 down the muck pile towards ramp unit 154 and, subsequently, to return blade 170 to the top of the muck pile. Blade 170 continues to be reciprocated through this path.

[0153] With each pass of blade 170 down the muck pile and towards ramp unit 154, the blade pulls muck material from the top of the pile and onto ramp unit 154. The ramp unit 154 then lifts the muck material to discharge unit 158. [0154] As noted, discharge unit 158 directs the received material onto the distal end of conveyor 138 of conveyor tram 130. As noted, speeds of conveyor 160 and conveyor 138 may be matched so that fragmented material is evenly distributed along the length of conveyor 138. Additionally or alternatively, discharge unit 158 may have a restrictor device limiting the rate at which material can be deposited onto conveyor 138. In some embodiments, conveyor 138 may be advanced in discrete increments, rather than continuously, so that rock material is discharged onto conveyor 138 in discrete piles.

[0155] Loading of conveyor 138 in this manner continues until the entire upward-facing length of conveyor 138 is loaded with material. Conveyor tram 130 is then moved along rail 120 towards main tunnel 104 to offload material.

[0156] Removal of material from the muck pile may pause until the conveyor tram returns after unloading, or until another conveyor tram 130 arrives to receive material. At that point, material removal continues in the same manner.

[0157] During removal of muck, ramp unit 154 and outrigger unit 156 may be repositioned to collect material from different parts of the muck pile. For example, ramp unit 154 and outrigger unit 156 may be twisted to a different angular orientation relative to rail 120, such that material can be collected from portions of the muck pile adjacent side walls 118.

[0158] Removal of material continues until the muck pile is substantially entirely removed. Thereafter, face 109 and the surrounding area are prepared for a new blast.

[0159]At box 304, drilling apparatus 200 is advanced to the distal end of rails 120 and boom 206 is extended toward face 209. Boom 206 is moved to the drilling configuration of FIG. 9A, i.e. , with a drill of tool holder 212 facing roof 114. A series of holes are drilled in roof 114 to receive bolts for anchoring ground support structure. In some embodiments, additional holes may be bored in side walls 118 for receiving rock bolts. To drill such holes, drilling apparatus 200 may be moved to a position with a drill of tool holder 212 facing a side wall 118 (FIG. 8). [0160] At box 306, platform apparatus 220 is advanced to the distal end of rail 120 and platform 224 raised into position so that workers on platform 224 can access roof 114. Workers install rock bolts into the holes bored at box 304. Reinforcing structure is installed using the rock bolts. The reinforcing structure may include, for example, metal bars or arches, metal mesh, pillars, or any suitable structure, as will be apparent to skilled persons. The supporting structure may include devices for anchoring rail 120.

[0161] In embodiments with a single rail 120, drilling apparatus 200 is removed prior to platform apparatus 220 being moved towards face 109. In embodiments with multiple rails 109, platform apparatus 220 may be moved towards face 109 on another rail, while drilling apparatus 200 is held in its working position.

[0162] At box 308, drilling apparatus 200 is moved into a working position proximate face 109 (if necessary) and boom 206 is moved to the position of FIG. 9B, with a drill of tool holder 212 facing face 109. Holes are drilled in face 109 for receiving explosive charges. The number, size and spacing of explosive holes depends on the nature of the formation being blasted. For example, formations with large numbers of naturally- occurring cracks may be blasted with relatively little explosive.

[0163] At box 310, platform apparatus 220 is moved into a working position near face 109 and workers supported on platform 224 install explosive charges into holes drilled at box 308. Explosives transportation device 232 is moved into position behind platform apparatus 220 and explosive charges are injected through nozzles.

[0164]After installation of explosives, all personnel and machinery are moved in the proximal direction away from face 109, to a safe distance for blasting. The safe distance may depend, for example, on characteristics of the formation being blasted, and the number and size of charges, as will be apparent.

[0165] Explosives are detonated at box 312. Detonation may be triggered remotely by any suitable method.

[0166] Immediately after face 109 of tunnel 106 is blasted, a section of rock is broken down into fragmented material, leaving a new face 109 distal of the face that was blasted. New face 109 is spaced apart from rail 120 by a distance defined by the depth of the blasted rock section, plus the safety margin by which rail 120 was spaced apart from the previous face immediately prior to the blast.

[0167] After blasting, at box 314, new face 109 and surrounding sections of roof 114, floor 116 and side walls 118 are inspected visually and with the aid of instruments to verify stability and safety for further work.

[0168] Inspection may be performed by workers atop platform 224 of platform apparatus 220. Specifically, platform apparatus 220 may be advanced to the distal end of rail 120. Platform 224 may be extended toward new face 109 by articulation of linkage 226. Platform 224 may be moved laterally and vertically up and down across new face 109.

[0169] Upon satisfactory inspection, at box 316, a section is installed for each rail 120. The new sections mate to the existing rails, such that carriages 122 supporting apparatus can be moved from the existing rail onto the new section. The process then returns to box 302 for removal of fragmented material from the blast.

[0170] Process 300 repeats to propagate tunnel 106 in a distal direction away from its starting point.

[0171] FIG. 15 depicts main tunnel 104 in greater detail. Apparatus, personnel and material may be carried between the surface and any tunnel 106 by way of main tunnel 104.

[0172] Main tunnel 104 is equipped with a ground-mounted conveyor 400. Conveyor 400 may include an endless belt 402 driven by one or more electrical drive rollers (not shown), which may be operated at variable speed. Conveyor 400 may further be supported by one or more idler rollers (not shown). The endless belt 402 may have a plurality of spaced elevator partitions 404 attached thereto.

[0173] A loading chute 406 may be positioned above the conveyor 400 at a junction with a tunnel 106, to receive fragmented material from a conveyor tram 130 within the tunnel and direct the fragmented material onto conveyor 400. Specifically, rock material falling into loading chute 406 is directed into a pocket defined by an elevator partition 404. Conveyor 400 may be constantly or intermittently advanced to carry a filled elevator partition 404 away from chute 406 and towards the surface.

[0174] Loading of fragmented rock into each elevator partition 404 may be metered.

Metering may be achieved, e.g., using a measurement device on or proximate conveyor tram 130 to measure the amount of rock discharged. Additionally or alternatively, metering may be achieved by providing a fixed-size aperture on chute 406 and advancing conveyor 400 at a defined rate, such that each elevator partition 404 receives a maximum weight of material. Additionally or alternatively, one or more load sensors may be positioned on or under endless belt 402 or elevator partitions 404 to directly measure the load imposed on each elevator partition 404. Controlling load in this way may contribute to durability and reliability of conveyor 400.

[0175] Conveyor 400 is of modular construction. Specifically, conveyor 400 includes a plurality of sections, each having: a structure for supporting conveyor 400 on the floor of main tunnel 104; a portion of belt 402 with one or more elevator partitions 404; and one or more rollers supporting the belt portion. In some embodiments, all sections of conveyor 400 include at least one drive roller. In other embodiments, drive rollers may be present in only a subset of conveyor sections, e.g. every second section or every fourth section.

[0176] In the depicted embodiment, belt 402 has a core comprised of metallic links, with an outer cover. The outer cover may be, for example, woven fabric such as nylon fabric, or a resilient flexible polymeric layer such as a rubberized sheath.

[0177] Portions of belt 402 are connected by splice joints 410, depicted in FIG. 16.

Splice joints 410 are mechanically releasable couplings between portions of belt 402, and can pivot through a sufficient range of motion to easily pass around rollers at the ends of conveyor 400. In the depicted embodiment, each splice joint 410 comprises an array of interlocking links 412 at the ends of abutting sections of belt 402. Links 412 can be brought into registration with one another, and cooperatively define an opening through which a pin can be inserted. The pin locks the two sets of links 412 to one another, thereby joining the sections of belt 402 together. Other types of connections are possible, as will be apparent.

[0178] Tunnels can be excavated horizontally, with an incline gradient, or with a decline gradient. As depicted, main tunnel 104 is excavated downwardly as extraction from ore body 102 progresses. That is, tunnels 106 are excavated in sequence from top (closest to the surface) to bottom (farthest from the surface). Main tunnel 104 is correspondingly extended downwardly to service new tunnels 106.

[0179]As shown in FIG. 16, one or more rails 120 are also installed to the roof of main tunnel 104. In the depicted embodiment, two rails 120-3, 120-4 are present, although any number of rails may be used, subject to space constraints.

[0180] Any of conveyor tram 130, muck loading apparatus 132, drilling apparatus 200, platform apparatus 220, and explosives transportation unit 232 may be supported on and moved along rail 120, and may be used to excavate main tunnel 104 substantially as described above with reference to tunnel 106. That is, main tunnel 104 may have an end face 109’ and main tunnel 104 may be extended in steps by blasting a section of rock behind end face 109’ to define a new end face, and removing the blasted rock before blasting again.

[0181]As shown in FIG. 16, an example muck loading apparatus 132 is positioned to load fragmented material from a pile onto conveyor 400. That is, the muck loading apparatus 132 of FIG. 2 is positioned with its ramp unit 154 proximate the pile and its discharge unit 158 atop conveyor 400 so that fragmented material falls from discharge unit 158 onto conveyor 400.

[0182] In other embodiments, a conveyor tram 130 may be arranged in series behind muck loading apparatus 132 and overlapping conveyor 400, such that fragmented material is transferred from muck loading apparatus 132 to conveyor tram 130, and then to conveyor 400.

[0183] FIG. 17 depicts an example of such an arrangement. As shown, conveyor 400 is set back from face 109’ by a gap distance G. Conveyor tram 130 and muck loading apparatus 132 in combination span the gap distance between conveyor 400 and face 109’. Muck loader 132 spans a distance L and conveyor tram 130 spans a distance T. As depicted, the sum of distances L and T is greater than distance G. Therefore, muck loader 132 overlaps conveyor tram 130 and conveyor tram 130 overlaps conveyor 400. Such overlaps ensure that muck loader 132 can discharge fragmented material onto conveyor tram 130 and that conveyor tram 130 can discharge fragmented material onto conveyor 400.

[0184] With each blast at the end of main tunnel 104, face 109’ is extended farther away from conveyor 400. Conveyor tram 130 and muck loading apparatus 132 may move towards the new face 109’ such that they continue to span the gap. However, the overlap between components correspondingly decreases.

[0185] Conveyor tram 130 and muck loading apparatus 132 continue to incrementally move away from conveyor 400 with successive blasts, until a minimum overlap between muck loader 132 and conveyor tram 130 is reached, or until a minimum overlap between conveyor tram 130 and conveyor 400 is reached. In some embodiments, the minimum overlap may be zero, such that tram 130 and muck loading apparatus 132 incrementally move away from conveyor 400 until there is no overlap. An additional section may then be installed to extend conveyor 400 so that the conveyor and tram 130 again overlap, and continue blasting.

[0186] Thus, an additional section of conveyor 400 is installed for each set of blasts that cumulatively adds a distance to main tunnel 104 equivalent to the lengths of conveyor tram 130 and muck loading apparatus 132, less the overlaps required for operation. In an example, conveyor tram 130 is 30 metres in length and muck loading apparatus 132 spans a length of 12 metres.

[0187] In the absence of conveyor tram 130, new sections would have to be added to conveyor 400 much more frequently. Depending on the depth of each blast, new conveyor sections could be required after every blast. [0188] Conveyor 400 must be stopped in order to add a section. Therefore, the use of conveyor tram 130 intermediate conveyor 400 and muck loading apparatus 132 may avoid operational interruptions, and in turn, may increase productivity for mine 100.

[0189] In some embodiments, new sections may be added to conveyor 400 even less frequently. For example, blasting could continue until gap distance G between conveyor 400 and face 109’ is greater than the combined lengths T, L of conveyor tram 130 and muck loader 132. In such configurations, conveyor tram 130 may be loaded with fragmented material, then moved along rail 120 towards conveyor 400 until they overlap, prior to discharging the fragmented material onto conveyor 400.

[0190] In some embodiments, a modified conveyor tram may be used in main tunnel 104. FIGS. 18A-18B depict one such example conveyor tram 130’. In FIG. 18A, conveyor tram 130’ is shown in a retracted position. In FIG. 18B, conveyor tram is shown partially extended.

[0191] Like conveyor tram 130, conveyor tram 130’ is supported on a rail 120 by way of carriages 122 (not shown). Conveyor tram 130’ may also have a drive unit operable to propel conveyor tram 130’ along rail 120 by friction or by a geared interface.

Additionally or alternatively, tram 130 may be propelled by an external drive. For example, conveyor tram 130’ may be attached to a lifting device 702 such as a jack or a winch by way of a cable 704. The lifting device 702 may be mounted to the tunnel roof, as shown, or to the tunnel floor, or suspended on rail 120.

[0192] Conveyor tram 130’ has a conveyor with a belt 706. FIG. 18C shows a side schematic view of belt 706. As depicted, in some embodiments, belt 706 is generally flat, and has partitions 708 which project in a perpendicular direction from the surface of belt 706. Partitions 708 may be rigid or resiliently deformable, and define pockets in which fragmented rock can be received. When conveyor tram 130’ is used on an incline or decline, partitions 708 are positioned below piles of fragmented rock, and limit rock sliding down the belt 706. [0193]As depicted in FIGS 18A-18B, conveyor tram 130’ has a main section 710 which extends generally parallel to rail 120 and which at least partially overlaps conveyor 400, a loading section 712 which extends parallel to the floor of tunnel 104 and which underlies discharge unit 158 of loading apparatus 132, and a ramp section 714 which extends from main section 710 to loading section 712 at a decline angle.

[0194] , Lifting device 702 is operable to move conveyor tram 130’ up or down tunnel 104, thereby increasing or decreasing the length of main section 710 that overlaps conveyor 400.

[0195] In operation, as shown in FIG. 18B, conveyor tram 130’ may be extended towards the face of tunnel 104 and towards muck loading apparatus 132 to remove fragmented rock from a blast. Once the rock has been removed and the face is ready to be blasted again, conveyor tram 130’ may be withdrawn away from the face, to leave a defined minimum safe distance between the conveyor tram and the blast event. The minimum safe distance may depend, for example, on characteristics of the formation being blasted and characteristics of the explosives being used. In an example, the minimum safe distance may be 24 metres.

[0196] As noted, conveyor 400 is installed in sections. At the time a section is installed, it is spaced apart from the face of tunnel 104 by the minimum safe distance. Conveyor tram 130’ is extended to bridge the gap between the face and conveyor 400.

Subsequent blasts move the face farther away from conveyor 400, such that conveyor tram 130’ needs to bridge a larger gap. To do so, conveyer tram 130’ may be extended farther, resulting in a smaller overlap between main section 710 and conveyor 400. The range of distance that can be serviced with conveyor tram 130’ is defined by the length / of its main section 710. A new section of conveyor 400 is installed each time a set of blasts cumulatively increase the length of tunnel 104 by distance I.

[0197] In some embodiments, the length / is longer than a section of conveyor 400. Accordingly, new sections of conveyor 400 may be installed less frequently than would be required in the absence of conveyor tram 130’. In some examples, length / may be a multiple of the length of a conveyor section. In such an example, multiple conveyor sections may be installed each time operation of conveyor 400 is interrupted for addition of a section.

[0198] Loading section 712 and ramp section 714 may be supported on the floor of tunnel 104. For example, the loading section and ramp section may be supported on wheels which carry at least part of the weight of conveyor tram 130’. Alternatively, loading section 712 and main section 714 may be supported by fixed support structures.

[0199] Loading section 712 and ramp section 714 may be pivotably connected to main conveyor 400. For example, loading section 712 and ramp section 714 can be pivoted between an operational position in which the loading section rests against the floor of tunnel 104 (FIG. 18A), and a tramming position in which the ramp and loading section are stowed proximate rail 120.

[0200] FIG. 19 depicts a process 300’ of excavation in main tunnel 104. Process 300’ is substantially identical to process 300, except in addition to installation of a rail section at box 316, it is determined at box 318 if a new section of conveyor 400 is required. If so, at box 320, a section is installed.

[0201]To install a new section of conveyor 400, the conveyor is stopped. Prior to stopping, conveyor 400 may be unloaded of fragmented material. A support structure is erected on the floor of main tunnel 104 between the existing conveyor 400 and face 109’. Rolling elements are installed to the support structure for supporting belt 402. As noted, the rolling elements include at least one idler roller and may include one or more drive rollers.

[0202] A splice joint 410 at the lower-most end of belt 402 is released and a new section of belt is wrapped around the newly-installed rolling elements. Links 412 at both ends of the new belt section are aligned in registration with corresponding links 412 from the released splice joint 410. The registered links 412 are then locked together to form closed splice joints 410, joining the new section into belt 402.

[0203] Conveniently, conveyor 400 and rails 120 may in concert be capable of transporting apparatus, material and personnel up an incline substantially steeper than could be achieved with conventional ground vehicles such as trucks. Accordingly, main tunnel 104 may likewise be steeper than a tunnel designed to be serviced by trucks. For example, trucks may typically be capable of moving apparatus, material and personnel up a grade of 15% or less. In contrast, using conveyor 400 and rails 120, apparatus, material and personnel may be moved up a 58% grade or more.

[0204] As will be apparent, excavation of main tunnel 104 at a steeper incline may permit access to ore body 102 with a shorter main tunnel 104, shorter tunnels 106, or both. Accordingly, the cost of accessing the ore body may be substantially lower. Moreover, rails 120 and conveyor 400, operating in concert, may permit removal of material at a higher rate, further lowering the cost of resource production. Such lower costs may enable some resource deposits to be mined profitably which would not be profitable using conventional techniques. In addition, some resources may be physically inaccessible using conventional techniques but capable of mining using apparatus and methods disclosed herein.

[0205] In addition to excavation of material from main tunnel 104 and tunnels 106, apparatus and methods disclosed herein may be used for removing portions of ore body 102 between tunnels 106.

[0206] FIG. 20 is a flow chart depicting a process 900 of extracting material from between tunnels 106.

[0207] FIG. 21 depicts portions of two tunnels, namely, an overcut (upper) tunnel 106-1 and an undercut (lower) tunnel 106-2, with a supporting block 500 of ore body 102 therebetween. In an example, block 500 may be approximately 50 metres thick.

[0208] At box 902 and as shown in FIG. 21 , a plurality of drill holes 502 are bored through block 500, and extend downwardly from tunnel 106-1 to tunnel 106-2. Drill holes 502 are bored in a region of block 500 having thickness t and length I, hereinafter referred to as a blast region. In an example, the blast region has a thickness of about 10 metres and a length of about 30 m. However, these dimensions may be greater or smaller. In some embodiments, the thickness of the blast region is greater than that of the tunnels 106, in which case the tunnels may be widened in the blast region by excavating the surrounding rock.

[0209] Drill holes 502 may be bored by drilling apparatus 200 or another suitable drilling rig and are drilled in a pattern designed to break and fragment a portion of block 500. Each drill hole comprises a hollow bore in which explosives may be inserted, such that they rest at the lowermost portion of block 500 within the blast region.

[0210] At box 904 and as shown in FIG. 22, explosives may be placed in drill holes 502 by workers on a platform apparatus 220 in tunnel 106-1. Specifically, platform apparatus 220 and explosives transportation unit 232 move into place along rail 120 and platform apparatus 220 is articulated so that workers can access all drill holes 502 in the blast region.

[0211] At box 906 and as shown in FIG. 23, explosive charges in drill holes 502 are detonated, causing the lowermost portion of block 500 within the blast region to become fragmented and fall into a pile 504 in tunnel 106-2. After the blast, a void or stope 506 is created between the pile 504 and block 500.

[0212]At box 908, muck loading apparatus 132 and conveyor tram 130 are moved into place in tunnel 106-2 along rail 120 and fragmented material from pile 504 is loaded onto conveyor tram 130 and removed until material is able to slough from pile 504 towards tunnel 106-2, where it can be removed by muck loading apparatus 132.

[0213] If part of block 500 within the blast region remains intact, the process returns to box 904 and another set of explosive charges is installed in drill holes 502 for another round of blasting and material removal. The explosive charges may be positioned at the bottom of drill holes 502 by first dropping a plug down each drill hole to stop the explosive charge.

[0214] When the entirety of block 500 within the blast region has been blasted, a void is left between overcut tunnel 106-1 and undercut tunnel 106-2. At box 910 and as shown in FIGS. 24-25, blade 170 of muck loading apparatus 132 is mounted on a long line 510. A pair of carriages 122, each carrying a pulley 512, are moved into position above stope 506, by movement along rail 120 of tunnel 106-1. Long line 510 is attached to blade 170 and looped around pulleys 512 and a pulley at muck loading apparatus 132. For example, line 510 may be fed through pulleys 512 at tunnel 106-1 , then lowered to tunnel 106-2 and fed through the pulley at muck loading apparatus 132. Long line 510 may then be cycled back and forth to move blade 170 through a stroke along the top of pile 504, to draw material towards muck loading apparatus 132.

[0215] The positions of pulleys 512 can be moved along rail 120 to alter the stroke of blade 170. For example, as shown in FIG. 25, pulleys 512 are spaced far apart from one another, with one pulley 512 positioned at the distal extreme of rail 120 in tunnel 106-1. With the pulleys so positioned, the stroke of blade 170 may span substantially the entire length of pile 504. Alternatively, with pulleys 512 positioned close together as shown in FIG. 24, blade 170 may be moved through a relatively short stroke, for example, to remove only the material closest to loading apparatus 132.

[0216] When pile 504 is substantially cleared, if part of block 500 remains to be excavated, the process returns to box 902 and repeats for another part of block 500. If all of block 500 has been blasted and removed, the resulting void is filled with backfill material. The process then moves to another block to be excavated.

[0217] Material removal by process 900 may be relatively efficient. That is, material may be removed at a high rate or at a low cost compared to conventional processes.

[0218] As described above, muck is moved within a tunnel 106 by conveyor tram 130, and muck is loaded onto conveyor tram 130 by muck loading apparatus 132. However, in some embodiments, a muck box system may be used instead of or in addition to conveyor tram 130 and muck loading apparatus 132.

[0219] FIGS 26A-26B depict side schematic views of an example muck box system 600. Muck box system 600 includes a plurality of muck boxes 601 for receiving muck, which are releasably carried on rail 120. As shown in FIG. 26A, muck box system 600 includes a short haul carrier 700 and a long haul carrier 720. [0220] Short haul carrier 700 operates in a distal section of tunnel 106 proximate face 109, to load fragmented rock (muck) into muck boxes 601 . Long haul carrier 720 operates in a proximal section of tunnel 106 intermediate a junction with main tunnel 104 and the location of short haul carrier 700. Long haul carrier 720 shuttles muck boxes 601 back and forth between the junction with main tunnel 104 and an area accessible by short haul carrier 700. Specifically, long haul carrier 720 carries empty muck boxes 601 to short haul carrier 700 for loading, and carries filled muck boxes 601 to the junction with main tunnel 104 for unloading. Each of short haul carrier 700 and long haul carrier 720 may be driven by a locomotive, such as a diesel or battery- powered locomotive (not shown).

[0221] FIG. 26B depicts an enlarged view of muck boxes 601 . Each muck box 601 is supported on rail 120. Each muck box 601 is releasably suspended from a pair of bogies 629 which is supported on rail 120 by way of carriages 122 (FIG. 29).

[0222] Referring to FIG. 27, muck box 601 has a proximal end 602, a distal end 604, side walls 606, and a bottom wall 608. Muck box 601 defines a hollow interior suitable for receiving and retaining muck for transport along tunnel 106. Muck box 601 may also comprise a plurality of mounting points 612 for attachment to an overhead support. Eight mounting points 612 are depicted in FIG. 27, however, more or fewer mounting points may be present.

[0223] FIG. 28A depicts an enlarged view of distal end 604 of muck box 601 . Distal end 604 may have a gate 614. Gate 614 is releasably attached to side walls 606 at the gate’s top edge with a releasable retaining mechanism 610 and is attached to side walls 606 or to bottom wall 608 at the gate’s bottom edge with hinges 611 . Gate 614 can be closed to retain muck within muck box 601 in transit. Gate 614 can be released such that distal end 604 of muck box 601 is opened for loading of muck. As depicted in FIG. 28A, the height of gate 614 is substantially the same as that of muck box 601 .

[0224] In some embodiments, gate 614 may be omitted. For example, it may be possible to retain muck within muck box 601 without a gate if muck box 601 traverses only a horizontal level or very slight incline. [0225] Proximal end 602 of muck box 601 may have a partial or full-height wall 617 extending upwardly from bottom wall 608 (FIGS. 27, 28B). The wall may retain muck within muck box 601 and provide torsional strength. Muck box 601 may further include one or more braces extending between side walls 606 for torsional stiffness.

[0226] FIG. 28B shows a side view of muck box 601 . As shown, any of the walls of muck box 601 may have reinforcing struts 607.

[0227] FIG. 29 depicts suspension of muck box 601 from rail 120 in greater detail. Each muck box is mounted (e.g., bolted) to a box frame 624 at mounting points 612. A plurality of rail bogies 629 are coupled to rail 120 on carriages 122. Each muck box 601 is supported by a pair of rail bogies 629-1 , 629-2, supporting distal and proximal ends of muck box 601 , respectively. Hoists 630-1 , 630-2 (individually and collectively, hoists 630) are mounted to rail bogies 629-1 , 620-2, and a wire 620 from each hoist is pivotably coupled to box frame 624. For example, each wire 620 may have a hook (not shown), received by a ring on box frame 624. In some embodiments, wire 620 may be replaced by a chain.

[0228] Box frame 624 releasably couples to muck box 601 at mounting points 612. The releasable coupling at each mounting point may be by way of a hook received by a ring, an extendable rod that interlocks with a socket, a locking cam, or any other suitable mechanism. In some embodiments, the coupling may be automatically locked or released based on a control signal. For example, locking pins or cams may be solenoid-operated. Alternatively, the releasable couplings may lock automatically upon engaging mounting points 612 and may be manually released when muck box 601 is supported on floor 116.

[0229] Hoists 630 and wires 620 operate to lower muck box 601 towards floor 116 of the tunnel or raise muck box 601 towards roof 114 of the tunnel, as indicated by arrows w. To raise or lower muck box 601 , plurality of hoists 630 wind wires 620 in or out. [0230] FIGS. 30A-30C schematically depict a muck box 601 in raised, lowered and tilted positions, respectively. For simplicity, box frame 624 and rail bogies 629 are omitted from FIGS. 30A-30C.

[0231]As shown, hoists 630 have sufficient range to allow muck box 601 to be continually lowered until bottom face 608 of muck box 601 meets floor 116 of the tunnel. When supported by floor 116, muck box frame 624 may be released from wires 620 such that muck box 601 rests upon floor 116 of the tunnel and muck box frame 624 is available for attachment to wires 620 suspended from another set of rail bogies 629. Conversely, a muck box 601 resting upon floor 116 of the tunnel may be releasably attached to wires 620 by way of muck box frame 624 and raised by hoists 630 towards roof 114 of the tunnel.

[0232] Hoists 630-1 and 630-2 may wind wires 620-1 and 620-2 in or out at substantially the same rate such that bottom face 608 of muck box 601 is maintained substantially horizontal throughout the raising and lowering process (FIGS. 30A, 30B).

[0233] Alternatively, hoists 630-1 and wires 620-2 may operate to wind wires 620-1 and 620-2 in or out at different rates, or for different lengths of time, such that bottom face 608 of muck box 601 is at an angle to the horizontal.

[0234]As will be described in greater detail, while resting on floor 116 in the lowered position (FIG. 30A), muck box 601 can receive a load of fragmented waste rock or resource material for removal. While suspended in the raised position (FIG. 30B), muck box can be transported along rail 120. Muck box 601 can be placed in the tilted position (FIG. 30C), with its proximal end lowered relative to its distal end, to unload muck.

[0235] FIG. 31 depicts short haul carrier 700 in greater detail. Short haul carrier 700 provides a mechanism by which muck box 601 may be loaded with waste rock or resource material.

[0236] Short haul carrier 700 includes a pair of rail bogies 629 from which a muck box 601 is suspended. Short haul carrier further includes an outhaul unit 701 , and drag unit 704. Outhaul unit 701 is positioned distally of muck box 601 , i.e. , between muck box 601 and a face 109 of tunnel 106 (not shown in FIG. 31 ). Drag unit 704 is positioned proximally of outhaul unit 701 . In the depicted embodiment, drag unit 704 is also positioned proximally of muck box 601 , but may instead be positioned intermediate muck box 601 and outhaul unit 701 .

[0237] Outhaul unit 701 has a frame 702 suspended from rail 120 by carriages 122 and a boom 708 mounted to and extending distally of the frame. The frame 702 may be positioned near the end of rail 120, such that boom 708 of outhaul unit 701 extends beyond monorail 120. Boom 708 is sufficiently long to span a distance between the end of rail 120 and face 109 of tunnel 106. That distance corresponds to a minimum safe distance at which machinery must be positioned relative to a blasted rock face for equipment operation and recovery of blasted material. In the depicted embodiment, the distance is 3 metres. However, the distance may be larger or smaller.

[0238] Boom 708 is supported near its proximal end by the frame 702. Boom 708 is pivotable relative to frame 702 about a vertical axis, such that it can be angled towards one or the other of side walls 118 of the tunnel. Boom 708 may also be pivotable about a horizontal axis, such that the distal end of boom 708 can be pivoted toward roof 114 or toward floor 116 of the tunnel. Boom 708 may also be axially extendable towards or away from face 109.

[0239] Drag unit 704 is supported on rail 120 by carriages 122. Drag unit 704 includes a drag drum 705 operable to move a wire on the pulley.

[0240] Boom 708 supports a driven outhaul drum 710 at the boom’s distal end. A wire 712 runs from outhaul drum 710 to blade 714. A second wire 712 runs from drag drum 705 to blade 714. The blade hangs such that, under the influence of gravity, blade 714 rests on a muck pile 715. Blade 714 can be reciprocated through a stroke by the movement of wires 712 between a pulley at outhaul drum 710 and a pulley at drag unit 704. Pulling of blade 714 through its stroke pulls fragmented rock towards and into muck box 601. [0241] Rail bogies 629 of short haul carrier 700 are operable to position the muck box 601 and lower muck box 601 onto floor 116 so that gate 614 lies along the stroke of blade 714.

[0242] With gate 614 opened, blade 714 can enter muck box 601 through distal end 604 and pull fragmented rock into muck box 601 . Material pulled into muck box 601 by blade 714 forms a pile within the muck box. Wall 617 at the proximal end of the muck box may retain the pile.

[0243] In some embodiments, outhaul unit 701 may be fixed (e.g. pinned or bolted) to the end of rail 120, rather than being supported on rail 120 by carriages 122. In such embodiments, outhaul unit 701 is dismantled from rail 120 prior to extension of the rail.

[0244] FIG. 32 depicts a long-haul carrier 720. Long-haul carrier 720 comprises a plurality of rail bogies 629 from which muck boxes 601 are releasably suspended as in short haul carrier 700. In the depicted embodiment, long-haul carrier 720 comprises eight bogies 629, carrying four muck boxes 601 . Bogies 629 of long haul carrier 720 may be physically coupled to one another in a train. Alternatively, bogies 629 may be joined in pairs carrying a common muck box 601 . In such cases, long haul carrier 700 may be defined by bogies 629 carrying a plurality of muck boxes 601 and moving together.

[0245] Long-haul carrier 720 is operable to transport muck boxes 601 in series along rail 120 between a transfer location proximate short haul carrier 700 and the junction of tunnel 106 and main tunnel 104. Specifically, long-haul carrier 720 carries empty muck boxes 601 from a junction with main tunnel 104 to the transfer location, and carries filled muck boxes from the transfer location to the junction with main tunnel 104. At the transfer location, short haul carrier 700 and long-haul carrier 720 can place muck boxes 601 on floor 116 of tunnel 106 and can pick up boxes 601 for transport.

[0246] FIG. 33 depicts a top plan view of a junction between a tunnel 106 with a muck box system 600 and main tunnel 104. FIG. 34 depicts a cross-sectional view of the same junction, taken along section line A-A shown in FIG. 33. [0247] As shown, tunnel 106 passes above tunnel 104. A muck transfer system 800 is positioned between tunnel 106 and tunnel 104 in a transfer passage 802 excavated between the two tunnels.

[0248] Muck transfer system 800 comprises a transfer chute 804 and a feeder conveyor 806. Transfer chute 804 is positioned to receive material from muck boxes 601 and direct the material onto feeder conveyor 806.

[0249] Feeder conveyor 806 is a belt-type conveyor supported on the floor of passage 802 and positioned to receive material from transfer chute 804. Feeder conveyor 806 advances the received material and discharges it onto conveyor 400 in main tunnel 104.

[0250] A fragment screen 808 is positioned atop chute 804. Fragment screen 808 is configured to prevent fragments above a threshold size from passing into chute 804. In an example, the threshold size is 400 mm. Fragments larger than the threshold size remain atop screen 808. A robotic rock breaker 810 is positioned adjacent chute 804 for further breaking down of oversized fragments.

[0251] Long haul carrier 720 is configured to sequentially position filled muck boxes 601 above chute 804 and lower muck boxes to a tilted orientation, which may be referred to as a discharge angle. Material may then fall out of muck box 601 and onto transfer screen 808 of chute 804. As depicted, muck box 601 is tilted to discharge angle of 52 degrees to the horizontal. However, the discharge angle may vary. For example, the discharge angle may depend of geometry of muck box 601 , characteristics of material to be discharged, and spatial constraints such as the vertical extent of tunnel 106.

[0252] Discharge of fragmented material from chute 804 to feeder conveyor 806 may be metered. That is, chute 804 may have a large capacity to store fragmented material and may be configured to regulate the rate at which material is discharged onto feeder conveyor 806. For example, chute 804 may have the capacity to store approximately 50 tons of fragmented material. The capacity of chute 804 provides a buffer so that, at any given time, the rate of transfer of material into chute 804 from a muck bin 601 and the rate of discharge from chute 804 onto feeder conveyor 806 may differ. [0253] In some embodiments, metering may be achieved by adjusting speeds of conveyors 806 and 400. For example, conveyors 806 and conveyor 400 may be held at substantially identical linear speeds so that fragmented material does not accumulate on conveyor 400.

[0254] In operation, long haul carrier 720 carries a series of empty muck boxes to the transfer location for transfer to short haul carrier. Boxes 601 are lowered onto floor 116 of tunnel 106 using hoists 630. Once a box 601 is supported on floor 601 , box frame 624 is released from mounting points 612 and frame 624 is retracted.

[0255] Short haul carrier 700 is then positioned over a deposited empty box 601 . The short haul carrier lowers a box frame 624 into contact with the box using hoists 630. The frame is then coupled to mounting points 612 on the box, and box 601 and frame 624 are raised towards rail 120 to a height suitable for safe transport. Short haul carrier

700 then carries the empty box towards face 109 of tunnel 106.

[0256] When short haul carrier 700 is positioned at the distal end of rail 120, outhaul unit

701 extends over a muck pile 715 which lies proximate face 109. The empty muck box 601 is lowered onto the floor by hoists 630 and gate 614 is opened.

[0257] Blade 714 is drawn towards the distal end of outhaul unit 701 by outhaul drum 710, so that the blade rests atop the muck pile.

[0258] Drag drum 705 is then operated to draw blade 714 down the muck pile towards and into muck box 601 . Movement of the blade 714 gathers material from the muck pile 715 and pulls the material into muck box 601 . Subsequently, outhaul drum 710 is operated to return blade 714 to the top of the muck pile. Blade 714 continues to be reciprocated through this path.

[0259] During removal of material, outhaul unit 701 may be repositioned to collect material from different parts of the muck pile. For example, outhaul unit 701 may be twisted to a different angular orientation relative to rail 120, such that material can be collected a muck pile spread across the width of tunnel 106. [0260] Once muck box 601 is loaded with material, removal of material from the muck pile pauses. Gate 614 may be closed and short haul carrier 700 raises the muck box and transports it to the transfer location.

[0261] At the transfer location, the filled box 601 is lowered onto floor 116 and then released from box frame 624. Short haul carrier 700 then moves to pick up another empty box and continue with removal of the muck pile.

[0262] Long haul carrier 720 is then positioned over the filled muck box 601 that was placed on floor 116. The long haul carrier 720 lowers a box frame 624 into contact with the filled muck box 601. Box frame 624 is coupled to muck box 601 and the box and frame are raised for transportation.

[0263] If at least one box frame 624 of the long haul carrier 720 is not carrying a filled muck box, the long haul carrier awaits the next filled muck box. However, if all box frames 624 are carrying filled muck boxes, the long haul conveyor moves to the junction between tunnels 104, 106.

[0264] Long haul carrier then moves a muck box 601 into position above chute 804.

The muck box is tilted to a discharge angle and its contents are allowed to fall into chute 804 by way of screen 808.

[0265] This process repeats for each muck box attached to long haul carrier 720. Long haul carrier then returns empty muck boxes 601 to the transfer location for refilling by short haul carrier 700.

[0266] As described above, muck box system 600 includes both short haul and long haul carriers, and the short haul carrier includes a slushing mechanism, i.e. a mechanism for transferring material from a muck pile into muck boxes 601 .

[0267] In other embodiments, short haul carrier 700 may be omitted. An example of such a muck box system 600’ is illustrated in FIG. 35. [0268]As shown in FIG. 35, muck box system 600’ includes two rails 120-1 , 120-2. Optionally, muck box system 600’ may further include a third rail 120-3 positioned between rails 120-1 , 120-2.

[0269]A muck box carrier 700’ is positioned on each of rails 120-1 , 120-2. The muck box carrier includes a box frame 624 suspended from bogies 629 with hoists 630 (not shown). As shown, each muck box carrier 700’ is coupled to a muck box 601 positioned at a loading position.

[0270]A slushing machine 820 is positioned between rails 120-1 , 120-2 and located proximally of muck boxes 601 in the loading position. As depicted, slushing machine 820 is suspended from third rail 120-3. However, the slushing machine may instead be supported on floor 116, in which case third rail 120-3 may be omitted.

[0271] An outhaul unit 701 is positioned at the end of each of rails 120-1 , 120-2 and each outhaul unit has a respective independently controlled outhaul drum 710. Blade 714 is connected to both outhaul drums 710 and to a drag drum (not shown) positioned at slushing machine 820. The two outhaul drums 710 form a diverging angle from slushing machine 820. The diverging angle in turn defines an operating window 822 for blade 714. The operating window is generally triangular and is bounded by lines from the slushing machine 820 to each outhaul drum 710, and by a line between the two outhaul drums 710.

[0272] By coordinated operation of outhaul drums 710 and the drag drum at slushing machine 820, blade 714 may be extended to an arbitrary position within operating window 822 and then pulled toward slushing machine 820. Thus, it is possible to move blade 714 through a variable stroke without physical movement of outhaul units 701 .

[0273] Accordingly, blade 714 may be operated to pull material from muck pile 715 into muck boxes 601 supported from both of rails 120-1 , 120-2. Thus, boxes at both rails may be filled in sequence without movement of outhaul units 701 .

[0274]As shown in FIG. 35, jersey barriers 824 are positioned at the distal ends of muck boxes 601 . Jersey barriers 824 serve as funnels to direct material into the muck boxes, which may ease operation of slushing machine 820 and increase the rate at which material can be transferred into the muck boxes.

[0275] Jersey barriers 824 may be fixed, i.e. positioned on floor 116 and formed of concrete or metal. Alternatively, gate 614 of a muck box 601 may be configured to define jersey barriers 824 when opened. That is, the gate may include two doors which pivot about vertical axes, and a locking device to hold the doors in a diverging position once opened. As will be apparent, jersey barriers 824 may be used with muck boxes 601 of both muck box system 600 and muck box system 600’.

[0276] The embodiments detailed herein are intended as examples only and are in no way limiting of the invention. Modifications are possible, as will be apparent to skilled persons. The invention is therefore defined by the claims, as interpreted in view of the application as a whole.