ZA200602531B - Grout pack restraining system - Google Patents

Description

® . _ ga05/0283L

GROUT PACK RESTRAINING SYSTEM

FIELD OF THE INVENTION

This invention relates to a grout pack restraining swstem, more particularly to a res.training system for a yielding grout pack.

BA.CKGROUND TO THE INVENTION

The support of the hanging wall in mining stopess is one of the most basic req uirements in mining. Dependent on the type- and quality of rock being supported, the depth of mining, the prevalent field stresses, seismicity, stoping wid th and a number of other factors, stope support can vary across a vast range of mmaterials, configurations and systems. These include, among others, gum poles, timber and composite packs, steel props, backfill paddocks, unmined ore pillars, hanging wall rock anchors and any combination of the above.

Grout packs are among the increasingly utilized combination support products con sisting essentially of a support column formed by a geotextile bag holding cured cemented backfill or a similar cured cementious grout that is resistant to compression. The geotextile bag is usually proteected and supported against

® 3 EBe200° 775231 lateral dilation of" the pack under load by a wire or polyrmer mesh, as well as a set of additional wire or polymer rings surrounding the baag and mesh horizontally.

The grout colurmnn is usually combined with timber peoles that are required to suspend the bag, net and ring assembly prior to filling with grout.

For the purpos e of this background discussion, th e structural and support contribution of tlhe timber poles to the behaviour and performance of the grout pack shall be disregarded.

Under vertical (amxial) load the grout column reduces in length and dilates laterally according to the= Poisson's ratio of the grout material. Besides the cohesion of the cemented material, the geotextile bag (a), the surr<ounding mesh (b), as well as the restraini ng rings (c) all contribute in some measure to the support resistance of the= pack in that they restrain the lateral dilation of the grout column. (a) The geotextile material is usually woven or knitted from low tenacity polymer fibres and offers little lateral confinement as it stretches easily under load.

Although it will p-rovide some useful confinement, its pri mary function is to provide suitable contaimment for the grout slurry with optinal drainage and filtering properties. (b) The secondary mesh basically forms a support s tructure for the geotextile material, preverting excessive bulging (with the asssociated increased solids losses through the enlarged pores) under hydrostati c loading of the uncured grout slurry. To add some degree of yieldability to the cured pack, the netting wires (or fibres) are usually oriented at 45° to the axiss of the pack allowing the mesh to stretch in the horizontal direction, providing some additional lateral confinement to tlhe pack. (c) The lateral restraining rings are the major structural confinement of the pack and their strengths contribute directly and significantly~ to the support resistance of the pack. Im conventional grout packs the perfosrmance of these rings is essentially dependent on their material properties, characterised primarily by their tensile stresngth and elongation. Invariably there= is a trade-off in terms of

@® 4 these properties in that higher tensile strength generally goes with lower elongation and vice versa.

In stope support the stiffness of a support unit has to be carefully considered, however, as stronger and stiffer is not necessarily better, particularly in sei smic stress environments where, under dynamic loading, shear stresses in the hanging wall around a very stiff pack can exceed the strength of the rock resulting in hanging wall failure ("punching"). Under such conditions, a yielding support unit should be able to absorb large and/or sudden rock moverment without losing its structural integrity. Similarly, high closure stopes also require yieldability to safely absorb the energy of the closing hanging wall.

In conventional grout packs, the width-to-height ratio of the grout columns is insufficient to generate their own cemented material confinement wander compression and the simple tendon lateral restraining rings, as described in (c) above are, therefore, the only significant lateral confinement of these packs.

It is these rings that largely control the compression behaviour of the packs. At present, however, they do not permit adequate yielding of the packs frorm an unyielded initial condition to a fully yielded condition as they rely solely on material deformation to permit yielding. Yield is thus determined by the qual ity of the steel used for the elements. After expansion permitted by the material yield of the elements the elements break and expansion becomes uncontrolled.

In this specification, yield refers to two separate concepts: a) yield or elongation as a material property is the deformation of a material e.g., a metal) beyond its elastic limit; i.e. yield or elongati on is irrecoverable plastic deformation; b) yield as a structural property refers to the plastic deformation of a structure, e.g., a grout pack; an “unyielded condition” refers to the condition of the grout pack immediately after being filled and a “fully yielded condition” refers to the condition of the grout pack after koeing

® 5 subjected to axial loading wherein the diameter thereof increases according to the Poisson's ration «of the material of which the structure is composed.

OBBJECT OF THE INVENTION

It is an object of this invention to provide a grout pack restraining system which will at least partially alleviate the abovementioned problem.

SWMMARY OF THE INVENTION

In accordance with this invention there is provided a grout pack restraining system which includes a plurality of elongate elements shaped to extend about a grout pack and characterised in that the elements are configured to control ci rcumferential expansion of the grout paeck beyond the expansion permitted th rough material yield of the elements.

Asccording to one aspect of the invention there is provided for the elongate el ements to be configured to include ring=s of at least a first diameter and a second diameter, the first diameter being s-maller than the second and selected tos provide restraint in an unyielded conditiora.

Farther features of the invention provide for the rings to have a helical configuration; alternatively for the rings to oe concentric, and for the rings of the se=cond diameter to be secured to the rings of the first diameter.

A ccording to a second aspect of the invent ion there is provided for the elongate elements to include rings configured to hav-e a diameter which can be increased umnder predetermined radial force.

® 6

Further features provi de for the rings to have overlapping ends; for at least one collar to be provided over the overlapping ends to provide frictional resistance to relative movement of the overlapping ends; for a collar to be provided at each end; for the collar to be a ferrule, alternatively a chain link with its longitudinal axis inclined to that of the elongate element.

Still further features of the invention provide for the elongate element of each ring to be non-linear; and for there to be at least one undulation in the elongate element; alternately at least one loop in the elongate element.

The invention further provides an element for a grout pack restrainimg system, the element being shaped to extend about a grout pack and characterised in that it is configured to control circumferential expansion of the grout pack beyond the expansion permitted through material yield thereof.

According to one aspect of the invention there is provided for the elemment to be configured to include wings of at least a first diameter and a second diameter, the first diameter being smmaller than the second and selected to provide restraint in an unyielded condition.

Further features of the invention provide for the rings to have a helical configuration; alternatively for the rings to be concentric, and for the rings of the second diameter to be secured to the rings of the first diameter.

According to a second aspect of the invention there is provided for the element to include a ring config ured to have a diameter which can be increased under predetermined radial Force.

Further features provide for the ring to have overlapping ends; for at least one collar to the provided over the overlapping ends to provide frictional re sistance to

® rexlative movement of the overlapping ends; for a collar to be provided at each e nd; for the collar to be a ferrule, alternatively a chain lini with its longitudinal axis inclined to that of the element.

S-till further features of the invention provide for the ring to be non-linear; for there to be at least one undulation in the ring; alternately at least o ne loop in the ring.

T he invention also provides a method of restraining a grout pack which includes securing about the grout pack a plurality of elongate elements which are configured to control circumferential expansion of the grosut pack beyond the expansion permitted through material yield of the elements.

A ccording to one aspect of the invention there is provide fer rings of at least a first diameter and a second diameter to be secured about the grout pack, those off the first diameter being smaller than those of the second d iameter.

According to a second aspect of the invention there is pmovided for elongate el ements in the form of rings configured to have a diarmeter which can be in creased under predetermined radial force to be secured ab out the grout pack.

B RIEF DESCRIPTION OF THE DRAWINGS

The invention will be described, by way of example only, vvith reference to the accompanying drawings in which:

Fi gure 1 is a top plan view of a first embodiment of a grout pack restraining system;

Fi gure 2 is an isometric view of part of the grout pack restraining system in Figure 1;

© = 20086...

Figure 3 is a side elevation of a fastener used in the grou t pack restraining systerm in Figure 1;

Figure 4 is a front elevatio n of the fastener in Figure 3;

Figure 5 is a further side e=levation of the fastener in Figure 3;

Figure 6 is a side elevation of the grout pack restraining sysstem in

Figure 1 in use;

Figure 7 is a side elevation of the grout pack restraining sysstem in

Figure 1 in use;

Figure 8 is a side elevation of a fastener used in the grout pack restraining systerm in Figure 1 in an alternate arrangement;

Figure 9 is a side elevation of second embodiments of a faste=ner for use in a grout pack restraining system;

Figure 10 is a side elevatio n of third embodiments of a fastener —for use in a grout pack restraining system;

Figure 11 is a side elevation of fourth embodiments of a faste ner for use in a grout pa«ck restraining system;

Figure 12 is a top plan view of a second embodiment of a grout pack restraining systerm,;

Figure 13 is a top plan view of a third embodiment of a grouat pack restraining systerm;

® 9

Fisgure 14 is a isometric view of part of the grout pack restraining system in Figure 13;

Fiegure 15 is a top plan view of a fourth emmbodiment of a grout pack restraining system;

Fiegure 16 is a sectional end view of part of the grout pack restraining system in Figure 15;

Figures 17 to 19 are side elevations of part of thhe grout pack restraining system in Figure 15 moving frorm an unyielded to a fully yielded condition;

Fiegure 20 is a top plan view of the grout pack restraining system in

Figure 15 in a fully yielded conditio n;

Figgure 21 is a side elevation of the grout pack restraining system in

Figure 15 in use;

Figure 22 is a side elevation of the grout pack restraining system in

Figure 15 in use in a second configguration;

Figure 23 is a side elevation of the grout pack restraining system in

Figure 15 in use in a third configuration;

Figure 24 is a top plan view of a fifth emtoodiment of a grout pack restraining system;

Figure 25 is a isometric view of part of tkhe grout pack restraining system in Figure 24;

® 10

Figure 26 is a top plan view of a sixth embodiment of & grout pack restraining system;

Figure 27 is a isometric view of part of the grout pac k restraining system in Figure 26;

Figure 28 is a part sectional side elevation of an alternate collar for use in the grout pack restraining system in Figure 15 ;

Figure 29 shows side elevations of the collars in Figure 29 in use moving from an unyielded to a fully yielded cond ition;

Figure 30 is a side elevation of an elongate element —for use in a sevenths embodiment of a grout pack restraining system;

Figure 31 is a sid e elevation of part of the elongate elemment in Figure mov ing from an unyielded to a fully yielded ccondition;

Figure 32 is a tops plan view of a seventh embodiment of a grout pack restrain ing system;

Figure 33 is a side elevation of part of the grout pack restraining system in Figure 32;

Figure 34 is a side elevation of the grout pack restraini:ng system in

Figure 32 in use;

Figure 35 is a sicde elevation of the grout pack restraini ng system in

Figure 32 in use in a second configuration;

® 11

Figure 36 is a side elevation of the grout pack restraining system in

Figure 32 in use in a third c-onfiguration;

Figure 37 is a side elevation of the grout pack restraining system in

Figure 32 in use in a fourth configuration;

Figure 38 is a side elevation of the grout pack restraining system in

Figure 32 in use in a fifth configuration;

Figure 39 is a side elevation of an elongate element for use in an eighth embodiment of a grout pack restraining system;

Figure 40 is a top plan view of an ei ghth embodiment of a grout pack restraining system;

Figure 41 side elevation of part of thee grout pack restraining system in

Figure 41; and

Figure 42 is a side elevation of an elongate element for use in a ninth embodiment of a grout pac k restraining system.

DETAILED DESCRIPTION OF THE DRAWINGS

A first embodiment of a grout pack restraining system (1) is shown in Figures 1 and 2 and includes a pair of rings (2,3) each made from a steel rod with its ends welded together. The rings (2,3) have a first diameter and second diameter respectively, with the first diameter being small- er than the second diameter.

The rings (2,3) are concentrically arranged and secured to each other by a number of ties (5) spaced about the circumferesnces thereof. As shown in Figures

® 12 3 to 5, each tie (5) has a sleeve (6) moulde d from a plastics material which is a slidimng fit over the ring (2) and from which extends an integral flexible strap (7).

The distal end (8) of the strap (7) is slightly narrower than the remainder thereof and has a series of teeth (9) on one side the=reof. The end (8) can be fed through a slot (10) with a detent (not shown) thereim centrally located on the strap. This perrmits the end (8) to be fastened about the ring (3) in the manner of a conwentional cable tie with the rings (2,3) coaxial to each other.

In u se, as shown in Figure 6, a number of rings (2a to 2d) are secured over a grout pack (15) spaced along the length thereof and with the rings (3a to 3d) suspended therefrom. The diameter of the rings (2a to 2d) is selected to provide a tigght fit over the grout pack and provide resstraint in its unyielded condition.

Figuare 7 shows the grout pack (15) as it progressively yields under pressure from mowement of the hanging wall (20) towards the foot wall (21). Here, “closure” indicates the degree of movement of the ha nging wall (20) towards the foot wall (21) from the time at which the grout pack (1 5) is installed in position. Also, in this figur-e, only three ring sets (2a, 2c, 2e, 3a, 3c, 3e) are shown. It has been found in p ractice that grout packs yield by expan«ding and disintegrating from the top (23) downwards, as depicted. As this occurs , the grout pack gradually expands to engage the rings (3a to 3e) whilst still being restrained by the rings (2a to 2e). At appwoximately 20% closure the ring (2a) has yielded approximately 35% whilst the wring (3a) is tightly constricted about the grout pack (15). As expansion occurs dow~n the length of the grout pack (15) the rings (2c, 23) similarly yield whilst the ringss (3c, 3e) provide restraint.

At 3 Q% closure, the ring (2a) is fully yielded, showing its maximum design yield of abowmut 40%, whilst the ring (3a) restrains the grout pack (15) and continues yielding. The performance of the ring (2a) is assisted by the ring (3a). At 30% clos ure, ring (2e) is relatively undistorted with ring (3e) only commencing to restwrain the grout pack (15).

® 13

The grout pack restraining system thus permits controlled circumfere=ntial expansion of the grout pack between the unyielded condition and fully wield condition. This is in major part through configuring the system to pemit circumferential expansion of the grout pack beyond the expansion which would occur through simple yield of the rmaterial used in the system, in this embodirment by the provision of the rings of thes second larger diameter.

It will be appreciated, however, that many other embodiments of a grout pack restraining system exists which fall within the scope of the invention, particularly as regards the material used for the rings and the cross-sectional shape thereof.

Also, the rings can be secured in any convenient configuration and, as shown in

Figure 8, the ring (2b), adjacent ring (3a), can be suspended from the ring (3a) using a tie (5b). Also, ties of any suitable configuration can be used. As shown in

Figures 9 and 10, ties (30, 32), could include an elongate body (34, 35) with hook formations (36, 37) at either end thereof in which the rings (2a, 3a) cam be secured. As also illustrated in these figures, each body (34, 35) can have an arm (34a, 35a) extending laterally therefrom having a hook (36a, 37a) at the end thereof for securing a further ring (2b).

Further alternatively, as shown ira Figure 11, the ties (40, 41, 42) can simpl y be elongate bodies having apertures at either end thereof through which the rings (2a, 3a) can be inserted.

More than two rings of increasing diameter can also be used and it is not necessary for the rings to be co-axial. As shown in Figure 12, three rings (50, 51, 52) of different diameter can be used and these can be secured together at a single point (54) by welding or by using a fastener.

Further alternatively, a pair of rings (60, 61) of first and second diameter, ca n be secured together using a pair of helically extending elongate elements (63, 64).

® 14

This helical configuration in effect provides seve=ral restraining rings of increasing diameter sand provides a much smoother trans ition of restraining duty from the ring of sm aller diameter (60) to that of larger diarmeter (61).

It is, howwever, not necessary to use rings of different diameter to control expansiorm of a grout pack. Instead, a ring ecan be provided which can be increased in diameter through a predetermin ed radial force by virtue of its configurat.ion rather than through material deformation of the material of the ring.

As shown in Figures 15 to 17, a ring (70) providing part of a grout pack restraining system is formed from an elongate steel element (72) with the ends thereof (7-3, 74) overlapping. A collar (76, 77), in this embodiment a ferrule, is secured osver the overlapping sections at each end (73, 74). The ferrules (76, 77) are swage=d onto the overlapping ends (73, 74-) to permit relative movement of these. Thee swaging force determines the frictio nal resistance to movement. The ends (73. 74) are bent outwardly to prevent: them from pulling through the ferrules (776, 77).

Under predetermined internal force on the r-ing (70) its diameter increases through frictional yield between the overlappling ends (73, 74) as shown in

Figures 1 7 to 19. In the fully yielded condition, shown in Figures 19 and 20, the ferrules (a6, 77) abut preventing further relatives outward movement of the ends (73, 74) a nd hereafter the ring (70) yields through material deformation.

In use, ass shown in Figure 21, a plurality of rings (70a to 70g) are secured about a grout paack (15) spaced along the length there of. As described with reference to

Figure 7, closure of the hanging wall (20) and feoot wall (21) causes compression and a de=formation of the grout pack (15). Thme rings (70a to 70g) control the circumfereential expansion of the grout packs (15) initially through frictional resistance2 and thereafter by material deformatison until fully yielded as described above.

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Any suitable configuration of rings (70a to 70g) can be used. As illustrated in

Figure 22, the ring (70a to 70f) cam be positioned adjacent the upper end (23) of the grout pack (15) to control expeansion there. It is, however, not necessary to secure the rings (70) coaxilly with ®he grout pack (15). As shown in Figure 23, the rings could be secured elliptically about the grout pack to form a types of net jacket, and these could be intersgoersed with non-yielding rings of conventional construction.

Frictional expansion of the ring can also be achieved throughs other configurations. As illustrated in Figures 24 and 25, an elongate element (80) can be folded into a pair of overlapping rings (81, 82) with the diameter of the first ring (81) being of smaller diameter than that of the second ring (82) and of the desired initial restraining diameter in an unyielded condition. A ferrule (8 3) joins the overlapping portion of the elongate element (80) and provides frictional resistance to circumferential expamsion of the ring (81). It will be understood that expansion of the ring (81) causess similar contraction of the ring (82) and at the point where the rings (81, 82) haave equal diameter, both will undergo material deformation under continued expansion of a grout pack over which they are secured.

It will also be understood that the ring (81) could be formed with the end s of the elongate element (80) overlapping as described with reference to Figures 15 to 17 to provide further frictional exp ansion of this ring. With such a configuration it may be desirable to secure the overlapping portion of the elongate element together to prevent relative moverment. This will provide a grout pack restraining system which combines the characteristics of the system described with reference to Figures 1 and 2 with that of the system described with reference to

Figures 15 to 17.

Further alternatively, as shown in Figures 26 and 27, a pair of rings (90, 91) of equal diameter can be secured together by a contiguous helical member (93)

® 16 which provides different yield characteristics because of its length and also provides friction against the expanding grout pack.

Furthermore, any suitable means of providing frictional resistance between overlapping ends of a ring can be used. As illustrated in Figure 28, a chain link (100, 101) can be welded to ea ch end (73, 74) inclined to the axis of the elongate element and over the overlapping ends. Under relative movement of the ends, the chain links (100, 101) cause the ends moving relative to them to be deformed under tensile load and this deformation together with the accompanying friction provides the required yield resistance. The sequential expansion of the overlapping ends is shown in Figure 29 and is similar to that illustrated in Figures 17 to 19.

Resistance to expansion can also be achieved through use of a non-linear elongate element (110) as illustrated in Figure 30. Here, an elongate steel element is formed with a series of undulations (112) along its length. As illustrated in Figure 31, the ovexrall length of the element (110) is increased when the ends thereof are forced in opposite directions and the undulations reduce in magnitude until the element is linear. The increase in length for each undulation is indicated in Figure 31 by “x”.

A ring (120) formed from the elongate element (110) is shown in Figures 32 and 33 and is formed with the undulations extending in the axial direction. It will be understood that applying an internal radial force to the ring will cause an increase in diameter thereof against the resistance provided by the undulations to straightening. Rings (120a to 120g) are shown in use over a grout pack (15) in

Figure 34. Similarly to the restraining systems illustrated with reference to

Figures 7 and 21, the rings (120a to 120g) are secured over the grout pack spaced along the length thereof. The closure of the hanging wall (20) and foot wall (21) causes deformation of the grout pack (15) as previously discussed and this is controlled by the rings (1 20a to 120g) as illustrated in Figure 34.

@® it will be appreciated that the rings (120a to 120g) can be paired in a m eshed configuration as illustrated in Figure 35.

Alternatively, as shown in Figure 36, rings (120a to 120e) could be used together with non-expanding rings (130a, 130b) located co-axially about the grout pack (15) or in an elliptical configuration as shown in Figure 37. The rings (120a, 120b) could also be used with rings (70a to 70e) of the type described in Figures 15 to 17 as shown in Figure 38.

The degree of expansion can be controlled by the number of undulations in the elongate element. As shown in Figures 39 to 41, a single undulation (130) can be provided in the elongate element (131) to provide a ring (32) which provide s only a small degree of circumferential expansion.

Also, as shown in Figure 42, loops (140) can be provided in the elongate element (141) instead of undulations to permit expansion thereof.

The grout pack retraining system of the invention thus provides a simp le yet highly effective means to control circumferential expansion of a grout pack between an unyielded condition and a fully yielded condition. The elmngate elements of the system are configured to permit expansion of the grout pack about which they are secured greater than the expansion permitted by simple material deformation of the elements. Many other embodiments which fall within the scope of the invention will be apparent to a person skilled in the art.

Claims (32)

® 18 CLAIMS

1. A grout packs restraining system which includes a plurality of elongate elements shamped to extend about a grout pack and characteirised in that the elements are configured to control circumferential exparsion of the grout pack beayond the expansion permitted through material yield of the elements.

2. A grout packx restraining system as claimed in claim 1 im which the elongate elerments are configured to include rings of at | east a first diameter and a second diameter, the first diameter being sma ller than the second and seelected to provide restraint in an unyielded condit ion.

3. A grout pack restraining system as claimed in claim 2 in whiech the rings are concentric.

4. A grout pack mestraining system as claimed in claim 3 in which the rings of the second diaameter are secured to the rings of the first diameter.

5. A grout pack restraining system as claimed in claim 2 in which the rings have a helical configuration.

6. A grout packs restraining system as claimed in claim 1 ima which the elongate elements include rings configured to have a diamete r which can be increased munder predetermined radial force.

7. A grout pack westraining system as claimed in claim 6 in which a ring has overlapping ends with at least one collar to the provideed over the overlapping e nds to provide frictional resistance to relative nmovement of the overlappirag ends.

o i”

8. A grout pack restraining system as clairmned in claim 7 in which a collar is provided adjacent each end.

9. A grout pack restraining system as clairmed in claim 7 or claim 8 in which the or each collar is a ferrule.

10. A grout pack restraining system as clairmed in claim 7 or claim 8 in which each collar is a chain link arranged with its longitudinal axis inclined to that of the elongate element.

11.A grout pack restraining system as claimed in claim 6 in which the elongate element of a ring is non-linear.

12. A grout pack restraining system as clainmed in claim 11 in which there is at least one undulation in the elongate elerment.

13. A grout pack restraining system as claimed in claim 11 in which there is at least one loop in the elongate element.

14. An element for a grout pack restraining =system, the element being shaped to extend about a grout pack and characterised in that it is configured to control circumferential expansion of the grout pack beyond the expansion permitted through material yield thereof.

15.An element as claimed in claim 14 which is configured to include rings of at least a first diameter and a second diameter, the first diameter being smaller than the second and selected teo provide restraint in an unyielded condition.

16. An element as claimed in claim 15 in which the rings to have a helical configuration.

17. An element as claimed in claim 15 in which the rings are cancentric.

18.An eleement as claimed in claim 17 in which the ring of the second diame-ter is secured to the ring of the first diameter.

19. An element as claimed in claim 14 in which the element includes a ring config ured to have a diameter which can be increased under predetermined radial force.

20. An ele=ment as claimed in claim 19 in which the ring has overlapping ends.

21.An element as claimed in claim 20 in which at least one cOllar is provided over ®he overlapping ends to provide frictional resistamnce to relative moverment of the overlapping ends.

22.An element as claimed in claim 21 in which a collar is provided at each end.

23. An ele=ment as claimed in claim 22 in which the collar is a ferrule.

24. An element as claimed in claim 22 in which the collar is aa chain link with its longitudinal axis inclined to that of the element.

25. An ele=ment as claimed in claim 19 in which the ring is non-I inear.

26. An ele-ment as claimed in claim 25 in which there is at least one undulation in the wring.

27.An ele ment as claimed in claim 25 in which there is at least one loop in the ring.

28. Ax method of restraining a grout pack which includes securing about the grout pack a plurality of elongate elements which are configured to control circumferential expansion of the grout pack be yond the expansion permitted through material yield of the elements.

29.A method as claimed in claim 28 in which rings of att least a first diameter and a second diameter are secured about the grout pack, those of the first di ameter being smaller than those of the second diarmeter.

30.A method as claimed in claim 28 in which elongate e-lements in the form of rimgs configured to have a diameter which can be increased under predetermined radial force are secured about the grout pack.

31.A grout pack restraining system substantially as hewein described and as illustrated with reference to Figures 1 to 11 or Figure= 12 or Figures 13 and 14 or Figures 15 to 23 or Figures 24 and 25 or Figures 26 and 27 or Figures 28 and 29 or Figures 30 to 38 or Figures 39 ®o 41 or Figure 42.

32. A method of restraining a grout pack substantially ass herein described and ass illustrated with reference to Figures 1 to 11 or Figure 12 or Figures 13 and 14 or Figures 15 to 21 or Figure 22 or Figure 23 or Figures 24 and 25 or Figures 26 and 27 or Figures 28 and 29 or Figures 30 to 34 or Figure or Figure 36 or Figure 37 or Figure 38 or Figures 39 to 41 or Figure 42.

DATED THIS 28" DAY OF MARCH 2006. { GILFILLAAN INC. (JOHN & KERNICKD FOR THE APPLICALNT