WO2025000048A1

WO2025000048A1 - System and method for ground stabilisation

Info

Publication number: WO2025000048A1
Application number: PCT/AU2024/050700
Authority: WO
Inventors: Samuel William THOMAS
Original assignee: Jusand Nominees Pty Ltd
Current assignee: Jusand Nominees Pty Ltd
Priority date: 2023-06-29
Filing date: 2024-06-28
Publication date: 2025-01-02
Anticipated expiration: 2025-12-29

Abstract

The present disclosure relates to a system for ground stabilisation in mining. The system comprises: an injection apparatus for insertion into a bore drilled in rock strata to introduce a ground-stabilising substance into the rock strata, the injection apparatus comprising at least one feed line for conveying the ground-stabilising substance, or a component thereof, into and along the bore, and an end assembly provided at an end of the at least one feed line for directing or delivering the ground-stabilising substance into the strata. The injection apparatus includes a coupling for connecting the feed line(s) in fluid communication with the end assembly, wherein the coupling is adapted to be released or decoupled from the end assembly remotely to separate the at least one feed line from the end assembly when located in situ inserted within the bore. The system further includes a delivery apparatus for inserting the injection apparatus into the bore, preferably a distance up to or more than 50 metres into the bore, wherein the delivery apparatus includes an advancement member for advancing the insertion of the injection apparatus into the bore.

Description

SYSTEM AND METHOD FOR GROUND STABILISATION

Technical Field

[0001 ] The present disclosure relates to a system and method for ground stabilisation, especially for use in mining applications. More particularly, the system and method are concerned with the introduction of a ground-stabilising substance into rock strata in an underground environment.

[0002] It will be convenient to hereinafter describe the present disclosure in relation to a system and method for ground stabilisation in mining. As will be appreciated, however, the system and method of this disclosure are not limited to mining environments and may also find applications in a range of civil engineering and/or construction environments, in which earthworks are involved.

Background Art

[0003] Any reference to, or discussion of, background art, including to any documents, herein is intended to facilitate an understanding of the present disclosure only and is not to be considered as an admission that such background art forms part of the state of the art or is widely known or forms a part of the common general knowledge in the relevant field in Australia or in any other country at the date of this application.

[0004] The introduction of resins, grouts and other such substances is known in mining and civil engineering applications for ground stabilisation, including uses such as, but not limited to, the consolidation of poor ground conditions, filling of cavities, creation of water barriers or water ‘curtains’ and blocking of aquifers. For the purposes of this description, the reference to a “ground-stabilising substance” is intended to cover such resins, grouts, cementitious products, or any other similar products designed to be used for introduction into rock strata to improve or alter its properties. Similarly, it will be appreciated that, where the present application refers to “rock strata”, this term will be understood as referring to all kinds of ground strata and it is not limited to earth or ground strata comprised of rock.

[0005] There are many resins and grouts used as ground-stabilising substances having different material properties, such as set times, expansion ratios, and strengths. As a consequence, these resins and grouts are typically intended or suited for use in a range of different applications. The process for introducing the resin or grout into the rock strata typically involves pumping them in liquid form into a bore under pressure. The resin or grout then flows from the bore into adjoining cracks and voids in the strata, thereby filling them. Over a period of time, the resin or grout expands and/or sets in the strata to provide the desired stabilising effect. The techniques and methodologies for introducing the ground stabilising substance also vary depending on the desired outcome. For example, resin or grout can be injected in stages (called “stage grouting”) throughout the length of a bore or targeted at a specific depth. Other examples include reducing water egress into tunnel workings or consolidating poor ground conditions to minimise over-break in drill and blast mining.

[0006] In current mining and civil engineering applications, there are limitations in the techniques and methodologies for the injection of ground stabilising substances into the strata to improve or alter its properties. These limitations particularly concern the injection of the substances into ‘long holes’ and include, among other things, the problem of how to get the substance to the required depth and how to retrieve the injection equipment upon completion. Typically, for holes that extend either horizontally or upwards in a range from horizontal to vertical (i.e., ‘up holes’), the injection is limited to approx. 15 to 20 metres. For holes drilled in a downward direction (i.e., ‘down holes’), the range is greater (approx. 40 metres) as the resin hoses can be lowered into the holes under gravity and resins with a longer cure time can be used. While the above values are not intended to be definitive, they nevertheless provide a general guide to the current practice in industry. It will be appreciated that operators can have some flexibility, for example, in the cure time of resins by the addition of retardant chemicals or specially designed products which may allow for mixed resin to be pumped at distances greater than approximately 15 to 20 metres. The depths or distances remain substantially limited, however.

[0007] In view of the above, it would be desirable to provide a new or improved system and method for ground stabilisation, with which it is possible to address the geotechnical properties of rock strata via ‘long holes’, especially upwardly directed or extending holes (i.e., ‘up holes’), at lengths significantly in excess of 20 metres.

Summary

[0008] According to one broad aspect, the present disclosure provides a system for ground stabilisation in mining, the system comprising: an injection apparatus for insertion into a bore drilled in rock strata to introduce a ground-stabilising substance into the rock strata. The injection apparatus comprises at least one feed line for conveying the ground-stabilising substance, or at least a component thereof, into and along the bore, and an end assembly provided at an end of the at least one feed line for directing or delivering the ground-stabilising substance into the strata. The injection apparatus includes a device for separating or releasing the at least one feed line from the end assembly when located in situ inserted within the bore.

[0009] In this way, one of the problems limiting the introduction of the ground-stabilising substances, e.g., resins and grouts, to greater depths, namely the cost of the apparatus that is lost or sacrificed in the process, is addressed by the present disclosure. Another of the problems limiting introduction of the ground-stabilising substances to greater depths, namely the time needed to deliver a sufficient quantity to those greater strata depths, is addressed by providing a means by which the ground-stabilising substance can effectively be delivered to that depth (i.e., any desired depth) before it is mixed to initiate curing. In other words, the problem of the ground-stabilising substance starting to harden or cure before it reaches a desired location or site at greater depth within the bore is addressed by being able to initiate curing at any depth and then to separate or release remotely the at least one feed line from the end assembly to retrieve the feed line(s). That is, the device is adapted for actuation remotely from the in situ location of the end assembly in the bore.

[0010] In an embodiment, the device for separating or releasing the at least one feed line from the end assembly when located in situ inserted within the bore may comprise a means for severing a connection between the at least one feed line and the end assembly. The injection apparatus may include a single feed line for conveying the ground-stabilising substance into and along the bore to be injected into the strata at the desired location.

[001 1 ] In an embodiment, the device includes a member for severing or releasing the connection, and an actuator for the member that is operable remote from the end assembly to sever or release the connection, e.g., by decoupling or by cutting or shearing.

[0012] In an embodiment, the injection apparatus comprises a plurality of feed lines for conveying the ground-stabilising substance, or components thereof, into and along the bore. In this way, the components of the ground-stabilising substance, e.g., of a ground-stabilising resin, can be conveyed via the separate feed lines along substantially the entire length of the bore to a desired location or site in the strata and then mixed in situ in the end assembly at or close to the location or site where the resin is to be injected. The plurality of feed lines are provided in fluid connection with the end assembly for delivery of the ground-stabilising substance (i.e., resin) into the strata, and the device for remotely separating or releasing the feed lines from their connection with the end assembly (e.g., by severing or releasing that connection) provides the ability to retrieve the feedlines. The device or means for releasing that connection is preferably a releasable coupling.

[0013] In an embodiment, the injection apparatus includes a coupling for connecting the at least one feed line in fluid communication with the end assembly, and the coupling is adapted to be released or decoupled from the end assembly remotely to separate the at least one feed line from the end assembly when located in situ inserted within the bore.

[0014] In an embodiment of the disclosure, the coupling comprises a mechanism for releasing the connection between the at least one feed line and the end assembly and an actuator for the mechanism that is remotely operable to release the connection between the at least one feed line and the end assembly.

[0015] In an embodiment, the mechanism for releasing the connection between the at least one feed line and the end assembly includes an engaging member, such as a latch or locking member, that is movable from an engaged position to a disengaged position. The actuator is configured to move the engaging member from the engaged position to the disengaged position to release the connection between the at least one feed line and the end assembly. The actuator is preferably operable pneumatically or hydraulically or electrically or mechanically to release the connection between the at least one feed line and the end assembly. In other words, a range of means for operating the actuator are envisaged by the disclosure, including pneumatic and hydraulic (i.e., pressure) means, as well as electrical and mechanical means. The electrical means for operating the actuator includes wireless operation or wireless actuation (e.g., radio-controlled actuation). Thus, the system may comprise wireless technology to communicate between an operator and the coupling to release or decouple the feed line(s) from the end assembly.

[0016] In an embodiment, the system further comprises an actuator line which extends to the coupling, e.g., along or generally parallel to the at least one feed line, to operate the mechanism for releasing the fluid connection between the at least one feed line and the end assembly. The actuator line may, for example, be selected from a group consisting of: an electrical line, a hydraulic line, a pneumatic line, and a mechanical line (e.g., a cable). In this way, the actuator line may extend from the coupling back to an operator located in an access tunnel from which the system may be deployed into the bore. The actuator line, e.g., a pneumatic, hydraulic, electrical, or mechanical line, for operating the actuator, thus provides for remote operation of the actuator by an operator in the access tunnel to release or decouple the feed line(s) from the end assembly when the end assembly is located in situ inserted within the bore for recovering non-sacrificial parts of the injection apparatus.

[0017] In an embodiment, the system comprises a delivery apparatus for inserting the injection apparatus into the bore in the rock strata, and preferably for inserting the injection apparatus a distance of more than 15 metres into the bore, more preferably for inserting the injection apparatus a distance of up to 50 metres or even more into the bore, including up to and/or beyond a distance of 100 metres; e.g., up to 500 metres.

[0018] According to another aspect, the disclosure also provides a system for ground stabilisation in mining, in which the system comprises: an injection apparatus for insertion into a bore drilled in rock strata to introduce a ground-stabilising substance into the strata, and a delivery apparatus for inserting the injection apparatus into the bore in the strata, wherein the delivery apparatus includes an advancement member for advancing insertion of the injection apparatus into the bore. The injection apparatus typically comprises at least one feed line for conveying the ground-stabilising substance, or at least a component thereof, into and along the bore, and an end assembly provided at an end of the at least one feed line for directing or delivering the ground-stabilising substance into the strata. As noted above, the delivery apparatus is designed for inserting the injection apparatus a distance of more than 15 metres into the bore, preferably a distance of up to or more than 50 metres into the bore, and more preferably up to and beyond a distance of 100 metres.

[0019] In this way, the delivery apparatus of the disclosure is adapted or configured to carry, convey, or transport the injection apparatus along the bore to the desired location or site in the bore for introducing the ground stabilising substance. The delivery apparatus may preferably act to protect or shield the injection apparatus, and especially the at least one feed line, during its insertion along the bore.

[0020] In an embodiment of the disclosure, the advancement member of the delivery apparatus is adapted to be pushed or driven into the bore, especially from an access tunnel or location from which the bore is drilled. The injection apparatus, preferably the at least one feed line thereof, is adapted to be attached or secured to the advancement member in use in order to be conveyed or advanced into the bore with the advancement member. [0021 ] In an embodiment, the advancement member is adapted to be pushed or driven into the bore by a force that allows the advancement member to progress in a longitudinal direction of the bore. Thus, the force is usually applied in an axial or longitudinal direction of the bore and/or in an axial or longitudinal direction of the advancement member. This is typical, for example, where the bore is horizontal or upwardly inclined (i.e. , an ‘up-hole’) and the advancement member comprises, for example, a relatively stiff strand or rod or pipe that can be axially pushed or driven into the bore. In such a case, the advancement member may comprise a cable, rod, tube, or sheath, e.g., a steel cable or steel rod, that exhibits substantially more longitudinal stiffness or rigidity than the at least one feed line. In this regard, the advancement member may be provided in predetermined lengths, which are configured to be connected together for greater extent as the injection apparatus is advanced or inserted with the advancement member into the bore. Alternatively, the advancement member may also be substantially continuous, and may be, for example, provided wound on a spool or reel from which it can be unwound as the injection apparatus is progressively advanced or inserted into the bore with the advancement member.

[0022] In an alternative embodiment, the advancement member may be more flexible for inserting the injection apparatus into a downwardly inclined bore (i.e., a ‘down-hole’). The advancement member may nevertheless comprise a cable, rod, tube, or sheath, e.g., a steel cable or steel rod, but it may have a small diameter and be more flexible than is required in the case of an ‘up-hole’ as the insertion into a ‘down-hole’ is assisted by gravity. The advancement member may thus, again, be substantially continuous and provided on a spool or reel from which it can be unwound as the injection apparatus is advanced or inserted into the bore together with the advancement member. In this context, the delivery apparatus may include a winch for lowering the injection apparatus into the downwardly inclined bore.

[0023] In an embodiment of the disclosure, the end assembly includes a nozzle through which the ground-stabilising substance is directed or delivered into the rock strata at a desired location or site in the bore. To this end, the nozzle typically has at least one outlet opening, and preferably a plurality of outlet openings, through which the ground-stabilising substance is discharged into the strata. The end assembly preferably includes a fixing member, such as an inflatable collar or ‘packer’, for fixing and/or holding the end assembly in position against side walls of the bore at the desired location or site in the bore while the ground-stabilising substance is discharged into the strata. The fixing member operates to allow the resin or grout to be injected into the strata under pressure. An inflatable collar or packer is advantageous as the fixing member because it may close or seal off the bore and thereby prevent the resin or grout from flowing back down the bore. The nozzle may comprise a fitting, or it may simply comprise an open end of a feed pipe or feed line.

[0024] In an embodiment, each outlet opening of the nozzle has a closure, such as a plug or a stopper or a hinged cover, preferably held therein under friction, to prevent unwanted ingress of dirt and/or grit into the outlet opening (s) of the nozzle prior to supply of the ground-stabilising substance. The pressure of the supply of the ground-stabilising substance into the nozzle is designed to forcibly remove (e.g., to eject) the closure (e.g., plug or stopper) from each of the outlet openings in the nozzle as the ground-stabilising substance is introduced into the strata via the end assembly.

[0025] According to a further aspect, the present disclosure also provides a method of ground stabilisation, comprising steps of: inserting an injection apparatus into a bore drilled in rock strata, the injection apparatus including at least one feed line for conveying a ground-stabilising substance, or at least a component thereof, into and along the bore, and an end assembly provided at an end of the at least one feed line for delivering the ground-stabilising substance into the rock strata; introducing the ground-stabilising substance into the strata via the at least one feed line and end assembly of the injection apparatus; and releasing or decoupling the at least one feed line from the end assembly when the end assembly is located within the bore in order to retrieve the at least one feed line, preferably after a step of introducing the ground-stabilising substance into the strata via the injection apparatus.

[0026] In an embodiment, the step of releasing or decoupling the at least one feed line from the end assembly comprises actuating a mechanism in a coupling provided between the at least one feed line and the end assembly to release a connection between the at least one feed line and the end assembly.

[0027] In an embodiment, the step of releasing or decoupling the at least one feed line from the end assembly comprises moving an engaging member, such as a latch or locking member, from an engaged position to a disengaged position to release the connection between the at least one feed line and the end assembly. [0028] In an embodiment of the disclosure, the step of actuating the mechanism in the coupling is effected pneumatically or hydraulically or electrically or mechanically to release the connection between the at least one feed line and the end assembly.

[0029] In an embodiment, the step of inserting the injection apparatus into the bore in the strata comprises advancing or pushing the injection apparatus via an advancement member, which is inserted with the injection apparatus into the bore.

[0030] According to yet a further aspect, the disclosure provides a method of ground stabilisation, comprising steps of: providing an injection apparatus having at least one feed line for conveying a ground-stabilising substance, or a component thereof, into and along the bore, and an end assembly provided at an end of the at least one feed line for delivering or discharging the ground-stabilising substance into the rock strata; inserting the injection apparatus into the bore by advancing or driving the injection apparatus in a longitudinal direction of the bore via an advancement member to which the injection apparatus is attached or secured; and introducing the ground-stabilising substance into the strata via the at least one feed line and end assembly of the injection apparatus.

[0031 ] In an embodiment, therefore, the method comprises connecting the at least one feed line to the advancement member for insertion into the bore, the advancement member comprising a cable or rod, preferably a steel cable or steel rod, that exhibits substantially more longitudinal stiffness or rigidity than the at least one feed line.

[0032] Generally, the present disclosure is intended to cover any and all adaptations or variations of the particular embodiments discussed herein. By way of example, a skilled person will readily appreciate that the system of this disclosure is not limited to being made from any specific material described in the embodiments. Rather, the skilled person will appreciate that a range of suitable materials exist and the skilled person can select a material based upon the known mechanical properties of that material which make it suitable for use in the system. As the present disclosure involves engineering technology from a number of disciplines, it is expected that the notional ‘skilled person’ may comprise a group or a team of individuals having technical expertise and/or qualifications in one or more of the following fields or disciplines: mechanical engineering, mining engineering, electrical engineering, hydraulic engineering, and geotechnical engineering. Brief Description Of The Drawings

[0033] For a more complete understanding of the invention of the present disclosure and the advantages thereof, exemplary embodiments are explained in more detail in the following description with reference to the accompanying drawing figures, in which like reference signs identify or designate like parts and in which:

Fig. 1 is a schematic perspective view of an injection apparatus for use in ground stabilisation close to a surface of a tunnel or drive;

Fig. 2 is a schematic side view of an injection apparatus for a ground stabilisation system according to an embodiment of the present disclosure;

Fig. 3 is a top view of the system for ground stabilisation according to the exemplary embodiment of the disclosure;

Fig. 4 is a side view of the system for ground stabilisation shown in Fig. 3;

Fig. 5 is a side view of the system for ground stabilisation according to an embodiment of the present disclosure prior to the introduction of resin into the strata;

Fig. 6 is a side view of the system for ground stabilisation shown in Fig. 5 after the introduction of resin into the strata;

Fig. 7 is a side view of the system for ground stabilisation shown in Fig. 5 after release of the coupling connection between the feedlines and the end assembly;

Fig. 8 is a cross-sectional side view of the nozzle of the end assembly in Figs. 5 to 7;

Fig. 9 is a side view of the nozzle shown in Fig. 8 with stoppers;

Fig. 10 is a schematic side view of a mechanism and actuator for releasing the coupling between the feed line(s) and the end assembly according to one embodiment of the disclosure;

Fig. 1 1 is a schematic side view of a mechanism and actuator for releasing the coupling between the feed line(s) and the end assembly according to another exemplary embodiment of the disclosure; and Fig. 12 is a schematic side view of a mechanism and actuator for releasing the coupling between the feed line(s) and the end assembly according to a further exemplary embodiment of the disclosure.

[0034] The accompanying drawings are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of this specification. The drawings illustrate particular embodiments and together with the description serve to explain the principles of the invention. Other embodiments and many of the attendant advantages will be readily appreciated as they become better understood with reference to the following detailed description.

[0035] It will be appreciated that common and/or well understood elements that may be useful or necessary in a commercially feasible embodiment are not necessarily depicted in order to facilitate a more abstracted view of the embodiments. The elements of the drawings are not necessarily illustrated to scale relative to each other. It will also be understood that certain actions and/or steps in an embodiment of a method may be described or depicted in a particular order of occurrences while those skilled in the art will understand that such specificity with respect to sequence is not actually required.

Detailed Description Of The Embodiments

[0036] As noted at the outset, the introduction of resin, grout and other such substances for ground stabilisation is known in mining and civil engineering applications, including for uses such as the consolidation of poor ground conditions, filling of cavities, creation of water barriers or water ‘curtains’, and the blocking of aquafers. The process for injecting a resin into the strata typically involves mixing two components and pumping the mixture into the bore under pressure with the resin flowing into and through the cracks and voids in the strata and thereby filling them. The different types of resins available have different applications and different material properties, such as set times, expansion ratios, and strengths. As with resin, there is a wide variety of cementitious products, such as grouts and microfine cements, that are also injected under pressure into the strata. Again, the process typically involves mixing the product and injecting it into a bore under pressure with the grout or microfine cement filling the voids and cracks in the strata. For the purposes of this description, the reference to a “ground-stabilising substance” is intended to cover such resins, grouts, cementitious products, or any other similar products designed for introduction into rock strata to improve or alter its properties. [0037] With reference to Fig. 1 of the drawings, an example of a conventional system for ground stabilisation in mining is illustrated. The system includes: an end assembly E having a feed pipe F, a packer P, and a nozzle N inserted within a bore B drilled in rock strata R for directing or delivering a ground-stabilising substance S (i.e., a resin) into the strata, and two feed lines L1 , L2 for conveying components A, B of the resin S separately into a static mixer M upstream of the feed pipe F. As noted earlier, for bores that are drilled either horizontally or upwards at an angle (i.e., ‘up holes’), including those extending vertically, the depth of the injection is limited to about 15 to 20 metres into the bore with this conventional arrangement.

[0038] Referring to Figs. 2 to 9 of the drawings, an example of a system 1 for ground stabilisation in mining according to an embodiment of the present disclosure is illustrated. The system 1 comprises an injection apparatus 10 for insertion into a bore B drilled in rock strata R to introduce a ground-stabilising substance S into the rock strata. In this particular embodiment, the injection apparatus 10 comprises two feed lines 11 , 12 provided in the form of flexible tubes or hoses for conveying two components A, B of the ground-stabilising substance S (i.e., the resin) separately into and along the bore B, and an end assembly 13 provided at or connected to an end of each of the feed lines 1 1 , 12 for directing or discharging the ground-stabilising substance or resin S into the strata R. For this purpose, the end assembly 13 includes a nozzle 14 for directing and discharging the resin S into the strata R. The end assembly 13 typically also includes a fixing member 15, e.g., in the form of an inflatable collar or packer, for fixing or holding the end assembly 13 in the desired location against side walls of the bore B as the resin S is injected into the strata R under pressure. The inflatable collar of the fixing member 15 also closes or seals off the bore B to prevent back-flow of the resin S in the bore.

[0039] As seen in Figs. 5 to 9, the nozzle 14 has a plurality of outlet openings 16 through which the resin S is discharged into the strata R. As seen in Fig. 9, each outlet opening 16 in the nozzle 14 may have a removable plug or stopper 17, e.g., held under friction, to prevent dirt or grit from entering and clogging the outlet openings 16 of the nozzle 14 during insertion into the bore and prior to supply of the resin S. Referring further to Fig. 2, the end assembly 13 of this embodiment may include a static mixer 18 located a short distance immediately upstream of the discharge nozzle 14 for mixing the two components A, B to form the resin S. The end assembly 13 may optionally also include a short feed pipe 19 located between the static mixer 18 and the fixing member 15. [0040] With further reference to Fig. 2, but also to Figs. 10 to 12 (to be discussed in more detail later), the injection apparatus 10 includes a coupling 20 for connecting the feed lines 1 1 , 12 in fluid communication with the end assembly 13. That is, the two components A, B of the resin S can flow under pressure from the feed lines 1 1 , 12 via the coupling 20 into the static mixer 18 before passing into the nozzle 14 for discharge through the outlet openings 16. As shown in Fig. 2, the coupling 20 does not need to be located between the feed lines 1 1 , 12 and the static mixer 18, but could instead be located between the static mixer 18 and the fixing member or ‘packer’ 15. The coupling 20 is adapted to be released or decoupled from the end assembly 13 remotely so as to separate the feed lines 11 , 12 from the end assembly 13 when located in situ inserted within the bore B. In this way, the system 1 makes it is possible to retrieve the feed lines 1 1 , 12 from deep inside the bore B after the resin S has been injected through the nozzle 14 under pressure into the strata R. To this end, the coupling 20 includes a device 21 for releasing the connection between the feed lines 1 1 , 12 and the end assembly 13 and an actuator 22 for the device 21 that can be operated remotely to release the connection between the feed lines 1 1 , 12 and the end assembly 13. The actuator 22 includes an actuator line 23 that extends to the coupling 20 generally parallel to the feed lines 11 , 12 from an access tunnel T for remotely operating the device 21 to release the fluid connection between the feed lines 1 1 , 12 and the end assembly 13. As described in more detail later, the actuator line 23 may be selected from a group consisting of: a hydraulic line, a pneumatic line, a mechanical line (e.g., a cable), and an electrical line or wireless communication means. Thus, the actuator 22 is operable either hydraulically, pneumatically, mechanically, or electrically to release the connection between the feed lines 1 1 , 12 and the end assembly 13.

[0041 ] With reference to Figs. 3 and 4 of the drawings, the system 1 includes a delivery apparatus 30 for inserting the injection apparatus 10 into the bore B in the strata R by a distance of more than 15 metres, and preferably a distance of more than 100 metres into the bore B. The delivery apparatus 30 includes an advancement member 31 for advancing the insertion of the injection apparatus 10 into the bore. In this regard, the advancement member 31 may comprise a steel cable, rod, or tube with substantially more longitudinal stiffness or rigidity than the feed lines 1 1 , 12, such that it is adapted to be pushed or driven into the bore B by a force applied in an axial or longitudinal direction of the bore B and/or an axial or longitudinal of the advancement member 31 . The injection apparatus 10, and especially the feed lines 11 , 12, are attached or secured to the advancement member 31 in use to be conveyed or advanced into the bore together with the advancement member. As a steel cable with some degree of flexibility, the advancement member 31 may be held or provided wound on a spool or reel 32 from which it is able to be unwound as the injection apparatus 10 is advanced or inserted with the advancement member 31 into the bore B. The advancement member 31 can thus be transported to the work site on the spool or reel 32 and can be fed from the reel into the bore B, e.g., via a strand pusher 33. An advantage of using a relatively stiff, yet flexible continuous element, such as a steel cable, as the advancement member 31 is that a length of cable, e.g., a 300 metre length, can be transported to the site on the spool or reel 32, the dimensions of which make it favourable for use in mine tunnels that have a limited width and height, but also advantageous for use from the surface. As an example, a 300m length of cable housed on a 2.5m diameter spool or reel would be suitable for use in a tunnel of dimensions 5.5m width W x 5.5m height H. Similarly, each of the feed lines 1 1 , 12 (i.e., as flexible tubes or hoses) may be provided on its own spool or reel 34, 35 for a compact supply and storage of the feed lines 1 1 , 12. The resin feed lines 1 1 , 12 and associated components, such as the static mixer 18, can be attached to the steel cable 31 , e.g., attached with tape, cable ties 36, screws, swaging, or any suitable means. As such, when the steel cable 31 is fed into the bore B, the end assembly 13 and the feed lines 11 , 12 are effectively ‘dragged’ into the hole with the cable 31 , thereby enabling the deployment of the injection apparatus 10 to the required depth. In this capacity the steel cable provides the relatively stiff ‘back bone’ to enable the flexible elements, such as feed lines 1 1 , 12, to be deployed into the bore. A guide member (e.g., tube) 37, with optional side access slot 38 and rotatable cover 39, may be mounted at the opening to the bore B to facilitate smooth deployment or insertion of the steel cable 31 and the injection apparatus 10 into the bore B and to reduce the chance of the cable being lodged in a side wall of the bore. Desirable properties of an appropriate steel cable are tensile strength, rigidity, modulus, and flexibility. An example of a suitable steel cable is high tensile prestressed concrete steel strand or PC strand which comes in many sizes, such as 12.7mm, 15.2mm and 17.8mm. This cable is typically used in the construction industry to stress concrete elements and for ground anchors in the civil engineering and mining industries. In addition to steel, other materials are conceivable, including other metals, composite materials, and engineering plastics. The height h of the spool or reel 32 may be adjusted to position the advancement member 31 of the delivery apparatus 30 for optimising the insertion of the injection apparatus 10 into the bore B.

[0042] As an alternative embodiment to that shown in Figs. 3 and 4, the advancement member 31 could be comprised of multiple steel sections, such as rods or pipes, e.g., in 3 metre lengths, which are joined together (e.g., via couplings or complementary male and female fittings) as they are being advanced into the bore B. The steel sections could be pushed axially into the bore B and retrieved using a hydraulic or a mechanical pushing I retracting device (e.g., a drill rig). Again, the feed lines 11 , 12 and associated elements, such as the static mixer 18, can be removably attached to, or fed through, the steel sections (e.g., rods or pipes). As the sections are advanced into the bore B, being joined together and pushed axially along, the end assembly 13 and the feed lines 1 1 , 12 are effectively ‘dragged’ into the bore with the advancement member 31 for deployment of the injection apparatus 10 to the desired depth. Thus, the steel sections again provide a ‘back bone’ to enable the flexible elements, such as feed lines or hoses 11 , 12, to be deployed into the bore B. Again, a guide member 37 can be used to enable smooth installation of the injection apparatus 10. The desirable properties of the steel sections are tensile strength, rigidity, and modulus. In addition to steel, other materials are conceivable, such as other metals, composite materials, and engineering plastics. Examples of engineering plastics include polyamide (PA, Nylon), polyethylene (PE, HDPE), polyvinylchloride (PVC), polycarbonate (PC) and polyurethane (PU). It will be appreciated that composite materials, such as fibre-reinforced polymers, may be suitable. With both embodiments - i.e. of a relatively stiff, yet partially flexible continuous advancement member 31 , on the one hand, and a relatively stiff advancement member 31 of limited flexibility, on the other - the following factors (as a non-limiting guide) should be considered when selecting a material for advancement member 31 : (i) mass of the feed lines 1 1 , 12 and resin to be inserted into the bore B, (ii) mass of the end assembly 13 and other parts to be inserted into the bore, (iii) strata type, (iv) how the bore was drilled e.g., cored drilled or percussion drilled, (v) angle of the bore, (vi) diameter of the bore, and (vii) how the feed lines 11 , 12 and other parts are attached to the advancement member.

[0043] Referring now to the drawing Figs. 5 to 7, when the delivery apparatus 30 has advanced the feed lines 1 1 , 12 and the end assembly 13 on the advancement member 31 to the desired location or depth in the rock strata R, as shown in Fig. 5, the nozzle 14 is in position to direct or discharge the resin S into the cracks and fissures C of the surrounding strata R. The fixing member or collar 15 is inflated to secure or fix the end assembly 13 in its position in the bore B and then the resin components A and B are supplied or fed under pressure through the feed lines 11 , 12 via coupling 20 into the static mixer 18 and onwards into the nozzle 14. The plugs or stoppers 17 are ejected from the outlet openings 16 of the nozzle 14 under the pressure of the resin S which, in turn, also passes through the outlet openings 16 into the rock strata R filling its cracks and fissures C around the end assembly, as shown in Fig. 6. At the conclusion of the pumping activity supplying resin components A and B through the feed lines 11 , 12, the device 21 of the coupling 20 is remotely actuated via actuator line 23 to release or decouple the feed lines 1 1 , 12 from the end assembly 13, as seen in Fig. 7, thereby to enable retrieval of the feed lines 1 1 , 12 by withdrawing the advancement member 31 with the delivery apparatus 30 (e.g., by retracting the rods and/or by winding the cable and the hoses back onto their respective reels 32, 33, 34) leaving the sacrificial elements of the end assembly 13, such as nozzle 14, the collar 15 and the static mixer 18, in the bore B.

[0044] There are a range of different combinations and dimensions available for parts of the resin injection apparatus 10, including the feed lines 1 1 , 12, the collar or packer 15, the static mixer 18, feed pipe 19 etc., and it is for an operator conducting the resin injection process to choose an appropriate location for the releasable coupling 20. For example, in a resin injection application in highly fractured ground, the operator conducting the resin injection may choose to locate the coupling 20 as much as 15-20 metres away from the collar or packer 15 in case of resin leakage into the bore B behind the packer 15 so as to avoid the coupling 20 from being inadvertently set or stuck in the bore due to the resin covering it and preventing it from working. The operator may also choose to provide a plurality of couplings 20 on the feed lines 1 1 , 12 (e.g., as in Fig. 2) to create redundancy in the event of an unexpected failure of the release device 21 (e.g. due to a faulty actuator 22). The coupling 20 may also be housed in a protective casing to prevent damage to the release device 21 and improve its functionality, e.g., to stop small rocks from blocking it.

[0045] As will be appreciated by persons skilled in the art, a range of different devices and mechanisms 21 are contemplated for releasing the connection of coupling 20 between the feed lines 11 , 12 and the end assembly 13. Some examples of such mechanisms 21 are illustrated in Figs. 10 to 12 of the drawings. In the case of Fig. 10, the actuator line 23 is a hydraulic line and the mechanism 21 includes a hydraulic piston or ‘ram’ 24 that drives a wedge or tapered element 25, which in turn interacts with an engaging member 26, such as a U-shaped latching member. When actuated by the hydraulic piston 24, the wedge or tapered element 25 lifts or moves the latching member 26 from an engaged position to a disengaged position, thereby releasing the connection of the coupling 20. The activation of the hydraulic mechanism, in this case the piston or ram 24, can be reliably carried out over a distance of many metres; e.g., over 100 metres. Suitable material properties for hydraulic mechanism include compressive strength, tensile strength, modulus, buckling, permeability. Suitable materials for the hydraulic mechanism include steel, other metals and their alloys, engineering plastics, composites. The hydraulic mechanism can employ any suitable hydraulic fluid, including oil or water.

[0046] In the case of Fig. 1 1 , the actuator line 23 is a pneumatic line and the mechanism 21 includes a pneumatic piston or ‘ram’ 24 that drives an engaging member 26 having a ball-detent 27 as a latching member. When actuated by the pneumatic piston 24, the ball detent 27 moves out of its latching engagement so that the latching member 26 moves to a disengaged position, thereby releasing the connection of the coupling 20. The activation of the pneumatic mechanism, in this case the piston or ram 24, can be reliably carried out over a distance of many metres; e.g., over 100 metres. Suitable material properties for pneumatic mechanism include compressive strength, tensile strength, modulus, buckling, permeability. Suitable materials for the pneumatic mechanism include steel, other metals and their alloys, engineering plastics, composites.

[0047] In the case of Fig. 12, the actuator line 22 is a mechanical line, such as a cable, and the mechanism 21 includes elements 28, 29 of a male and female connection held together by a latching member 26 provided at the end of the cable 22. When the actuator line is retracted or drawn, the latching member 26 is withdrawn from latching engagement with the male and female elements 28, 29 such that the latching member 26 moves to a disengaged position, thereby releasing the connection of the coupling 20. In an alternative example, the male and female elements 28, 29 could be held together by a U-shaped pin. As in Fig. 10, a wedge or tapered element could be drawn by the cable 23 under such a U-shaped pin, thereby releasing the coupling in a corresponding manner. The activation of the mechanical actuator can also be reliably carried out over a distance of many metres; e.g., over 100 metres. Suitable material properties for this device include tensile strength, compressive strength, modulus, buckling. Suitable materials for this device include steel, other metals and their alloys, engineering plastics, composites.

[0048] Although not illustrated in the drawings, the actuator line 23 may be an electrical line or a wireless electrical connection also. Examples of electrically actuated elements for such devices or mechanisms 21 include solenoids, which are able to generate short axial movements similar to a hydraulic or pneumatic piston in Fig. 10 or Fig. 11 , and electromagnets, which can switch polarity so as to switch from an attractive state (e.g., in an engaged position) to a repulsive state (e.g., in a released position).

[0049] Although specific embodiments of the disclosure are illustrated and described herein, it will be appreciated by persons of ordinary skill in the art that a variety of alternative and/or equivalent implementations exist. It should be appreciated that each exemplary embodiment is an example only and is not intended to limit the scope, applicability, or configuration in any way. Rather, the foregoing summary and detailed description will provide those persons skilled in the art with a convenient road map for implementing at least one exemplary embodiment, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope as set forth in the appended claims and their legal equivalents.

[0050] Generally, the present disclosure is intended to cover any and all adaptations or variations of the specific embodiments discussed herein. By way of example, a skilled person will readily appreciate that the system of the disclosure is not limited to being made from any specific material described in the embodiments. Rather, the skilled person will appreciate that a range of suitable materials exist and the skilled person can select a material based upon the known mechanical properties of that material which make it suitable for use in this system. As the present disclosure involves engineering technology from a number of disciplines, it is expected that the notional ‘skilled person’ may comprise a group or a team of individuals having technical expertise and/or qualifications in one or more of the following fields or disciplines: mechanical engineering, mining engineering, structural engineering, hydraulic engineering, and geotechnical engineering.

[0051 ] It will also be appreciated that the terms "comprise", "comprising", "contain", "containing", "have", "having", and any variations thereof, as used in this document are intended to be understood in an inclusive (i.e., non-exclusive) sense, such that the process, method, device, apparatus, or system described herein is not limited to the features, integers, parts, elements, or steps recited but may include other features, integers, parts, elements, or steps not expressly listed and/or inherent to such process, method, device, apparatus, or system. Furthermore, the terms "a" and "an" used herein are intended to be understood as meaning one or more unless explicitly stated otherwise. Moreover, unless indicated to the contrary, the terms "first", "second", "third", etc. are used merely as labels, and are not intended to impose numerical requirements on, or to establish a ranking of importance of, their objects. In addition, reference to positional terms, such as “lower” and “upper”, used in the above description are to be taken in context of the embodiments depicted in the figures, and are not to be taken as limiting the disclosure to the literal interpretation of the term but rather as would be understood by a skilled addressee in the appropriate context.

[00521 Drawing reference signs

1 system E end assembly

10 injection apparatus F feed pipe

1 1 feed line P packer

12 feed line N nozzle

13 end assembly B bore B

14 nozzle R rock strata

15 fixing member or collar S ground-stabilising substance or resin

16 outlet opening L1 feed line

17 plug or stopper L2 feed line

18 static mixer M static mixer

19 feed pipe C cracks and fissures

20 coupling

21 device or mechanism

22 actuator

23 actuator line

24 piston or ram

25 wedge or tapered element

26 engaging member or latching member

27 ball detent

28 male connection element

29 female connection element

30 delivery apparatus

31 advancement member

32 spool or reel

33 strand pusher

34 spool or reel

35 spool or reel

36 cable tie I fastener

37 guide member

38 slot

39 cover

Claims

1 . A system for ground stabilisation in mining, the system comprising: an injection apparatus for insertion into a bore drilled in ground strata to introduce a ground-stabilising substance into the ground strata, the injection apparatus comprising at least one feed line for conveying the ground-stabilising substance, or a component thereof, into and along the bore, and an end assembly provided at an end of the at least one feed line for delivering the ground-stabilising substance into the strata, wherein the injection apparatus includes a device for separating or releasing the at least one feed line from the end assembly when located in situ inserted within the bore.

2. A system according to claim 1 , wherein the device for separating or releasing the at least one feed line from the end assembly when located in situ inserted within the bore comprises means for releasing or severing a connection between the at least one feed line and the end assembly.

3. A system according to claim 2, wherein the device includes a member for severing or releasing the connection, and an actuator for the member that is operable remotely from the in situ location of the end assembly in the bore to release or sever the connection, e.g., by decoupling or by cutting or shearing.

4. A system for ground stabilisation in mining, the system comprising: an injection apparatus for insertion into a bore drilled in rock strata to introduce a ground-stabilising substance into the rock strata, the injection apparatus comprising at least one feed line for conveying the ground-stabilising substance, or a component thereof, into and along the bore, and an end assembly provided at an end of the at least one feed line for delivering the ground-stabilising substance into the strata, wherein the injection apparatus includes a coupling for connecting the at least one feed line in fluid communication with the end assembly, wherein the coupling is adapted to be released or decoupled from the end assembly remotely to separate the at least one feed line from the end assembly when located in situ inserted within the bore.

5. A system according to claim 4, wherein the coupling includes a device for releasing the connection between the at least one feed line and the end assembly and an actuator for the device that is remotely operable to release the connection between the at least one feed line and the end assembly.

6. A system according to claim 5, wherein the device for releasing the connection between the at least one feed line and the end assembly includes an engaging member, such as a latching member, that is movable from an engaged position to a disengaged position, and wherein the actuator is configured to move the engaging member from the engaged position to the disengaged position to release the connection between the at least one feed line and the end assembly.

7. A system according to any one of the preceding claims, wherein the actuator is operable either pneumatically or hydraulically or electrically or mechanically to release the connection between the at least one feed line and the end assembly.

8. A system according to any one of the preceding claims, wherein the injection apparatus includes a plurality of feed lines for conveying the ground-stabilising substance, or components thereof, into and along the bore, and wherein the plurality of feed lines are in fluid connection with the end assembly via the releasable coupling.

9. A system according to any one of the preceding claims, further comprising an actuator line which extends to the coupling to operate the device for releasing the fluid connection between the at least one feed line and the end assembly.

10. A system according to claim 9, wherein the actuator line is selected from a group consisting of: an electrical line, a hydraulic line, a pneumatic line, a mechanical line (e.g., a cable), and by a wireless connection (e.g., via radio).

1 1. A system according to any one of the preceding claims, wherein the end assembly includes a nozzle through which the ground-stabilising substance is directed or delivered into the rock strata, and a fixing member for fixing or holding the end assembly in a desired location against side walls of the bore, wherein the nozzle has at least one outlet opening through which the ground-stabilising substance is discharged.

12. A system according to claim 1 1 , wherein each outlet opening in the nozzle has a closure, such as a plug or stopper or a hinged cover, preferably held therein under friction, to prevent unwanted ingress of dirt and/or grit into the outlet openings of the nozzle prior to supply of the ground-stabilising substance.

13. A system according to any of the preceding claims, further comprising a delivery apparatus for inserting the injection apparatus into the bore in the strata, preferably for inserting the injection apparatus a distance of more than 15 metres into the bore, and more preferably for inserting the injection apparatus a distance of up to or more than 50 metres into the bore, including up to and beyond a distance of 100 metres, wherein the delivery apparatus includes an advancement member for advancing the insertion of the injection apparatus into the bore.

14. A system for ground stabilisation in mining, the system comprising: an injection apparatus for insertion into a bore drilled in ground strata to introduce a ground-stabilising substance into the strata, and a delivery apparatus for inserting the injection apparatus into the bore in the strata, wherein the delivery apparatus includes an advancement member for advancing insertion of the injection apparatus into the bore; wherein the injection apparatus comprises at least one feed line for conveying the ground-stabilising substance, or at least a component thereof, into and along the bore, and an end assembly provided at an end of the at least one feed line for delivering the ground-stabilising substance into the strata.

15. A system according to claim 13 or claim 14, wherein the advancement member is adapted to be pushed or driven into the bore, wherein a force is preferably applied in an axial or longitudinal direction of the bore or in an axial or longitudinal of the advancement member, for the advancement member to progress in a longitudinal direction of the bore, and wherein the injection apparatus, and preferably the at least one feed line, is attached or secured to the advancement member in use to be conveyed or advanced into and/or along the bore together with the advancement member.

16. A system according to claim 15, wherein the advancement member comprises a cable or rod, such as a steel cable or steel rod, that exhibits substantially more longitudinal stiffness or rigidity than the at least one feed line, and wherein the advancement member is held or provided wound on a spool or reel from which it is able to be unwound as the injection apparatus is advanced or inserted with the advancement member into the bore.

17. A system according to claim 15, wherein the advancement member has, or is provided in, predetermined, generally rigid lengths which are configured to be connected together for greater extent as the injection apparatus is advanced or inserted with the advancement member into the bore.

18. A system according to claim 13 or claim 14, wherein the advancement member comprises a cable, such as a steel cable, that is held or provided wound on a spool or reel from which it is able to be unwound as the injection apparatus is advanced or inserted with the advancement member into the bore, wherein the delivery apparatus includes a winch for lowering the injection apparatus into a downwardly inclined bore.

19. A method of ground stabilisation, comprising steps of: inserting an injection apparatus into a bore drilled in ground strata, the injection apparatus including at least one feed line for conveying a ground-stabilising substance, or a component thereof, into and along the bore, and an end assembly provided at an end of the at least one feed line for delivering the ground-stabilising substance into the strata; introducing the ground-stabilising substance into the strata via the at least one feed line and end assembly of the injection apparatus; and releasing or decoupling the at least one feed line from the end assembly in order to retrieve the at least one feed line when the end assembly is located within the bore, e.g., preferably after a step of introducing the ground-stabilising substance into the strata via the injection apparatus.

20. A method according to claim 19, wherein the step of releasing or decoupling the at least one feed line from the end assembly comprises actuating a mechanism in a coupling between the at least one feed line and the end assembly to release a connection between the at least one feed line and the end assembly.

21 . A method according to claim 20, wherein the step of releasing or decoupling the at least one feed line from the end assembly comprises moving an engaging member, such as a latch or locking member, from an engaged position to a disengaged position to release the connection between the at least one feed line and the end assembly.

22. A method according to claim 20 or claim 21 , wherein the step of actuating the mechanism is effected or occurs pneumatically, hydraulically, electrically, or mechanically to release the connection between the at least one feed line and the end assembly.

23. A method according to any one of claims 19 to 22, wherein the step of inserting the injection apparatus into the bore in the strata comprises advancing or pushing the injection apparatus in an axial or longitudinal direction of the bore via an advancement member to which the injection apparatus, especially the at least one feed line, is attached or secured.

24. A method of ground stabilisation, comprising steps of: providing an injection apparatus for a bore in ground strata, the injection apparatus having at least one feed line for conveying a ground-stabilising substance, or a component thereof, into and along the bore, and an end assembly provided at an end of the at least one feed line for delivering the ground-stabilising substance into the strata; inserting the injection apparatus into the bore by advancing or driving the injection apparatus in a longitudinal direction of the bore via an advancement member to which the injection apparatus is attached or secured; and introducing the ground-stabilising substance into the strata via the at least one feed line and end assembly of the injection apparatus.

25. A method according to claim 23 or 24, wherein the step of inserting the injection apparatus into the bore includes connecting the at least one feed line to the advancement member for insertion into the bore therewith, wherein the advancement member comprises an elongate member, such as a cable, rod, or pipe, that has substantially more longitudinal stiffness or rigidity than the at least one feed line.

26. A method according to claim 24 or claim 25, comprising releasing or decoupling the at least one feed line from the end assembly to retrieve the at least one feed line after the step of introducing the ground-stabilising substance, the method including a step of retrieving the at least one feed line from the bore.

27. A method according to claim 26, wherein the step of releasing or decoupling the at least one feed line from the end assembly comprises actuating a mechanism in a coupling between the at least one feed line and the end assembly to release a connection between the said at least one feed line and the end assembly.