GB2131850A - Hardenable structures for mine passages - Google Patents

Hardenable structures for mine passages Download PDF

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Publication number
GB2131850A
GB2131850A GB08332534A GB8332534A GB2131850A GB 2131850 A GB2131850 A GB 2131850A GB 08332534 A GB08332534 A GB 08332534A GB 8332534 A GB8332534 A GB 8332534A GB 2131850 A GB2131850 A GB 2131850A
Authority
GB
United Kingdom
Prior art keywords
bag
container
hardenable
base
walls
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
GB08332534A
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GB2131850B (en
GB8332534D0 (en
Inventor
Wayne Holt
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Monier Ltd
Original Assignee
Monier Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to AUPF727882 priority Critical
Priority to AUPG026683 priority
Application filed by Monier Ltd filed Critical Monier Ltd
Publication of GB8332534D0 publication Critical patent/GB8332534D0/en
Publication of GB2131850A publication Critical patent/GB2131850A/en
Application granted granted Critical
Publication of GB2131850B publication Critical patent/GB2131850B/en
Expired legal-status Critical Current

Links

Classifications

    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02DFOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
    • E02D29/00Independent underground or underwater structures; Retaining walls
    • E02D29/02Retaining or protecting walls
    • E02D29/0258Retaining or protecting walls characterised by constructional features
    • E02D29/0291Retaining or protecting walls characterised by constructional features made up of filled, bag-like elements
    • EFIXED CONSTRUCTIONS
    • E21EARTH DRILLING; MINING
    • E21DSHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D15/00Props; Chocks, e.g. made of flexible containers filled with backfilling material
    • E21D15/48Chocks or the like
    • E21D15/483Chocks or the like made of flexible containers, e.g. inflatable, with or without reinforcement, e.g. filled with water, backfilling material or the like

Abstract

Structures such as mine passageways closure walls and mine roof supporting piers are formed by filling bag-like containers (10) with grout or other hardenable material. The containers are suspended clear of the base surface and stretch to contact the base surface when partly filled. <IMAGE>

Description

SPECIFICATION Hardenable structures for mine passages Technical field This invention relates to methods and apparatus for the erection of wall and support structures of hardenable material, for use in such applications as the closure of mine passageways, piers for the support of mine roofs, and the formation of retaining walls and load-bearing walls in above-ground structures.

An object of the invention is the provision of such methods and apparatus in which the use of formwork is substantially eliminated.

Background art Present techniques in the closure of mine passageways by the erection of concrete closure walls or walls of bricks or blocks, require transport to the closure site of formwork, mesh or other building materials, as well as cement or mortar, and this involves considerable time and expense where, as is usually the case, the site is remote from the mine transport system.

Similar disadvantages are inherent in the techniques presently employed for the erection of supporting chocks or piers for mine roofs typically in long wall gate road support, and in the erection of roof-supporting dividing walls in single entry headings.

While these problems are less acute in aboveground situations, there are economic and practical advantages to be gained by employing the technique of the present invention in such situations as well.

It is known in the formation of concrete structures, particularly in underwater applications, to employ flexible bags of porous material which are filled with a hardenable material such as cement grout. Examples of such techniques are described in U.S. Patent 3,984,989 of Turzillo. In that disclosure however, the techniques used require formwork in the form of a matrix grid such as wire mesh.

A further example of the prior art is found in the technique, used in the United Kingdom, for the erection of underground roadway packings by the formation of a steel mesh framework in which a watertight textile bag is located, the bag being filled by pumping with a blend of Portland cement and a mixture of bentonite and sodium carbonate.

Disclosure of the invention The need for such restraint arrangements is eliminated in the present invention, which resides, in one form, in a method of erecting an upright structure of hardenable material comprising supporting above a base surface a flexible container comprising side walls and a base, said container being supported adjacent its upper end such that its base is clear of the base surface, and filling said container with hardenable material, the container stretching under the weight of said hardenable material to contact the base surface upon or prior to completion of filling.The invention also resides, in another form in means for the erection of an upright structure of hardenable material by a method according to claim 1 comprising a container of flexible material comprising sides and a base, support means by which the uppermost part of said sides may be supported, means at locations spaced about the height and width of said sides restraining them against outward movement.

In a container of substantially rectangular shape employed for mine passageway closure the means by which the front and rear side walls of the bag are restrained for limited outward relative movement may consist in the front and rear walls being sewn, woven or knitted together at intervals, particularly on vertical lines to form a series of parallel vertical tubular sections. Other techniques include the incorporation of integrally sewn, woven or knitted open mesh within the bag, inter-connecting the front and rear walls.

Where the techniques of the present invention are employed in the erection of roofsupporting piers of generally cylindrical crosssection, an advantageous form of restraint will consist of a series of vertically spaced circumferential bands applied, for example by sewing, to the external surface of the bag. Such bands may be made of webbing of the type used in seat belt harnesses, or otherwise of sufficiently strong material, and these bands may be incorporated in a removable and therefore reuseable harness suspended from the bag support.

Many other restraining arrangements are of course possible, with the general consideration being preventing such expansion of the bag during filling as will lead to bursting or to lack of vertical disposition, while avoiding the requirement of any rigid external restraint.

The bag material is selected for suitable strength and porosity, and may for example be of woven polyethylene or other synthetic fabric or natural materials. While it is not essential that the bag be of porous material, this is preferred as the resulting water egress enables mortar more rapidly to become self-supporting, and reduces the setting time.

It is of great importance that the bag, as it stretches under the increasing weight of mortar, does not contact the base surface of floor until a sufficient proportion of the bag, or of the bag portion being filled, has been filled with mortar. If the bag contacts the ground too early, sagging and lateral movement will occur, resulting in the wall curving out of a vertical plane and thereby reducing its load bearing ability. In extreme cases, bursting of the bag may also follow.

In the case of bags used for structural supporting purposes such as the gate road supports and piers referred to earlier, where the bag is of considerable width, the centre of the base will contact shortly after filling commences, but peripheral areas of the base should remain suspended by tension in the bag wall for some time to assist in preventing lateral distortion.

It is necessary therefore to support the bag at a distance above the base surface which is determined, by experiment, as correct for a particular bag material and dimensions. The extent of vertical stretching which will occur will also vary with the manner of fabrication of the bag and the manner in which the side walls aie restrained by sewing or other techniques. By the use of standardised bag designs and sizes, however, choice of the correct height setting of a given application will not be a matter of difficulty.

Brief description of the drawings In the accompanying drawings: Fig. 1 shows in front elevation, a bag suitable for use in the practice of the present invention; Fig. 2 shows a schematic side elevation of the manner of use of such a bag in the closure of a mine passageway; Fig. 3 shows in front elevation, a filled bag in such a passageway; Figs. 4a to 4d show various examples of bag construction in horizontal section; Fig. 5 shows a further example of bag construction, in front elevation; Figs. 6 and 7 illustrate a further example of bag construction; Fig. 8 shows in situ a mine roof support bag embodying the present invention; and Fig. 9 is a fragmentary detail of the manner of support of the bag of Fig. 8.

Embodiments of the invention The bag 10 illustrated in Fig. 1 consists of a rear wall (hidden) and a front wa'! 12, joined at intervals by vertical runs of stitching 13. Near the top of the bag there is provided a tube 14 which may be coupled to a supply of grout, and on the upper surface of the bag a number of loops 1 5 are provided for supporting the bag as described below. The bag is closed at the top to form a completely enclosed container.

In the example shown in Fig. 1 , the lines of stitching 1 3 are broken at intervals such as 1 6 to allow grout to flow between the vertical tubular passages formed by the rows of stitching, this being for the purpose of allowing the bag to fill evenly. This is by no means essential, and particularly where the bag is of great width, it may be desirable to fill in sections. Such an arrangement is shown in Fig. 5, where the bag is divided in two major sections, each with its own filling tube 14, and each divided by two lines of continuous stitching.

Fig. 2 illustrates a convenient manner of supporting the bag 10 in the use of the present invention in the closure of a mine passageway.

The bag 10 is suspended from beams 17 which are passed through the loops 1 5. The beams 17 are held against the roof of the mine passage by means of jacks or adjustable props 18, and the bag 10 is cantilevered on the beams 17, so that no supports or other equipment are required behind the bag and therefore lost upon closure of the passage.

The bag is supported above the floor of the mine 1 9 as described above, by a distance which is such that the bag will contact the floor only after the necessary proportion of the height of the bag has been filled. This proportion will vary according to the shape and size of the bag as explained above, and in some case may be less than one third of the height of the bag.

The bag is next filled with Portland cement grout or other hardenable material, by pumping the grout into the bag via the tube 14. As the bag fills, it expands against and conforms to the side walls of the tunnel, and as the bag becomes fuil, it expands also against the roof, around the beams 1 7, and conforms to the profile of the mine roof.

The bag must, of course, be chosen to be of a size which will be able to expand sufficiently to conform to the irregularities of the walls, floor and roof of the passageway in question.

Illustrated in Fig. 4 are four examples, by no means exhaustive, of bag construction.

The bag of Fig. 4a is formed from a single sheet of material, sewn back upon itself at vertical lines 1 3 to form vertical tubes 20, the free edges of the bag material being sewn at 21 to close the bag.

In the bag of Fig. 4b, the tubular portions 20 are formed by convoluting both the rear and front walls 11 and 12.

The bag illustrated in Fig. 4c is made up from fabric which is continuously woven to form the rear and front walls 11 and 12 with an integrally woven mesh 22 in the form of a continuous web joining the walls 11 and 12.

Illustrated in Fig. 4d is a further example of bag construction, where a series of vertical webs 23, sewn at their edges to the front and back walls 12 and 11, create the tubular spaces 20 and retain the walls against destructive bulging.

Figs 6 and 7 illustrate a further approach particularly suited to mining applications where passageway walls depart substantially from the vertical. This bag is constructed in the manner illustrated in Fig. 4d, but is provided at each side with an additional portion of somewhat arcuate shape formed by side walls 24. Webs 25 are provided in these additional portions, the webs 25 having apertures 26 through which mortar may flow during filling. The side portions may be selectively filled by separate nozzles 14, to take into account considerable variations in passageway conditions.

Illustrated in Figs. 8 and 9 is a bag suitable for use in forming monolithic roof support piers in the form of cylindrical columns.

In this case the bag 10 comprises a single cylindrical wall 27 sewn at a vertical seam (not shown). The bag is provided with a base attached by sewing to the lower edge of the wall 27, and a top closure similarly attached to the upper edge of the wall 27. A mortar filling nozzle 14 is of course provided.

At several points around the upper periphery of the bag flexible supporting loops 28 are sewn, from which the bag may be suspended with the upper edge of the wall 27 adjacent the mine roof.

These loops may, for example, be passed over a supporting ring 29 surrounding the upper edge of the bag, and fixed over hooks 30 attached to the outer part of the ring. The ring itself may be supported against the mine roof by props or jacks 31 engaged with spigots 32 which are provided on a series of radially disposed supporting arms 33.

In the case of the bag illustrated in Figs. 8 and 9, the means by which the walls of the bag are strengthened against expansion comprise a series of vertically spaced horizontal bands 34 of material of high tensile strength, such as webbing of the type used for automotive seat belts, sewn to the outside of the bag.

Bags of the design illustrated in Figs. 8 and 9 have been employed in the erection of roof supporting piers in a coal mine, with great success. Such bags are made in heights suited to the coal seam involved, typically from 1.75 to 5 metres. The experimental bags referred to were 2.5 m height and 1.1 m diameter, and were made up from 1 6x 16 weft and warp woven polyethylene fabric. With bags of these dimensions and material, the optimum initial gap between bag and floor was found to be approximately 75 mm. Generally speaking it has been found that the gap setting with polyethylene fabrics will be in the range of 50--100 mm. With other materials, having different strain or stretch characteristics a larger or smaller gap may be employed.

It may be found that slump of the grout on setting creates a cavity in the centre of the top of the bag, which is readily filled with mortar in a second operation.

Other bag configurations may of course be used in load-bearing applications. For example, a somewhat elliptical bag can be formed from a woven material of the type illustrated in Fig. 4c, with widely spaced sides 11 and 12. The techniques of the present invention will find use for centre roadway support in single entry heading applications, where bags of approximately two metres in thickness may be erected seriatim to form a continuous supporting wall.

In many mine passageway applications it will be found that the passageway floor is very uneven across the passageway, and it may be necessary to modify the bottom of the bag at the point of installation, by gathering portions of the bag and stapling, sewing or otherwise fixing the gathered or folded portions to leave the bottom of the bag at a substantially constant distance from the floor across the passageway. This technique can also be used to adapt the bag to the particular seam or passageway height at the closure site.

It will be appreciated that the bag may be formed in ways other than those illustrated, the essential characteristic being the provision of some means by which the walls are constrained to limit the expansion of the bag upon filling, preferably by means which connect the side walls or regions of the bag side at regular intervals.

The means of support provided for the bag at its upper end may similarly take many forms, and techniques for the support of the bag in underground applications, other than that described, will be apparent.

A particularly attractive technique involves the utilisation of steel plates which are attached to the passageway roof by roof bolts. Such plates are present throughout the passageways of many mines. The bag may be supported by means of eyelets or loops which engage suitable formations such as hooks, on wedges or spikes driven between the steel plate and the mine roof.

Other techniques which may be used inciude, in non-gassy mines, the use of explosive fastening devices.

In above-ground applications, different techniques will normally be convenient, as the bag may be supported front and back, or at the sides, for example by means of tubular pockets extending across the top of the bag, through which supports may be passed.

Other variations in construction may be adopted within the general teachings of this disclosure.

Claims (11)

Claims
1. A method of erecting an upright structure of hardenable material comprising supporting above a base surface a flexible container comprising side walls and a base, said container being supported adjacent its upper end such that its base is clear of the base surface, and filling said container with hardenable material, the container stretching under the weight of said hardenable material to contact the base surface upon or prior to completion of filling.
2. A method according to claim 1 for the erection of said structure underground, further comprising the steps of mounting a support against a roof surface, attaching the upper end of said bag to support, and filling said bag with hardenable material.
3. A method according to claim 2 wherein said bag is of generally cylindrical configuration, said support comprising a metal ring the inside diameter of which is substantially the diameter of said bag, said ring being fixed against the roof.
4. Means for the erection of an upright structure of hardenable material by a method according to claim 1 comprising a container of flexible material comprising sides and a base, support means by which the uppermost part of said sides may be supported, said container further comprising means at locations spaced about the height and width of said sides restraining them against outward movement.
5. Means according to claim 4 wherein said container comprises a pair of opposite side walls and a pair of opposite end walls, a base and a top wall, nozzle means adjacent said top wall for the introduction of hardenable material, said restraining means extending between said side walls within said container.
6. A container according to claim 5 wherein said restraining means comprise vertical panels joined at their opposite vertical edges respectively between said side walls.
7. A container according to claim 6 wherein said panels are provided with apertures for the passage of said hardenable material.
8. A container according to claim 5 wherein said restraining means comprises elements of the material of said container woven or knitted integrally therewith.
9. Means according to claim 4 wherein said container is substantially cylindrical, comprising a vertical wall, a base, and an upper wall, said restraining means comprising vertically spaced horizontal bands encircling said vertical wall.
1 0. A method of erecting an upright structure substantially as described herein.
11. Means for the erection of an upright structure of hardenable material substantially as described herein with reference to Figs. 1,4, 5 or 6, or Figs. 8 and 9, of the accompanying drawings.
GB08332534A 1982-12-15 1983-12-06 Hardenable structures for mine passages Expired GB2131850B (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
AUPF727882 1982-12-15
AUPG026683 1983-07-13

Publications (3)

Publication Number Publication Date
GB8332534D0 GB8332534D0 (en) 1984-01-11
GB2131850A true GB2131850A (en) 1984-06-27
GB2131850B GB2131850B (en) 1986-09-10

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GB08332534A Expired GB2131850B (en) 1982-12-15 1983-12-06 Hardenable structures for mine passages

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Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2154769A (en) * 1984-02-28 1985-09-11 Gandlake Software Ltd Computer software protection
GB2169630A (en) * 1985-01-16 1986-07-16 H L & H Timber Products Mat pack brick
EP0191570A2 (en) * 1985-01-29 1986-08-20 Alethea Rosalind Melanie Hall Support member
DE3602776A1 (en) * 1986-01-30 1987-08-06 Ketterer Klaus Method of securing the roadside edges in longwall face mining, and pack of construction material
GB2186607A (en) * 1986-02-14 1987-08-19 British Reinforced Concrete Eng Co Ltd Mine roof support pack for cementitious filling
EP0277670A1 (en) * 1987-01-21 1988-08-10 Digging Trading Company, N.V. Ground barrier
WO1990015224A1 (en) * 1989-05-30 1990-12-13 Fosroc International Limited Load support
US4983077A (en) * 1987-08-26 1991-01-08 Gebhardt & Koenig-Gesteins- Und Tiefbau Gmbh Method and an apparatus for producing fabric-reinforced lining supports or slender supporting structural units
GB2236089A (en) * 1989-10-19 1991-03-27 Flexadux Plastics Ltd Containment bags used in monolithic packing system etc
GB2245014A (en) * 1990-06-13 1991-12-18 Amco Plastics Ltd Means for filling a void
GB2296517A (en) * 1994-12-27 1996-07-03 H L & H Timber Prod Prestress grout bag
WO1999009299A1 (en) * 1997-08-18 1999-02-25 Fosroc International Limited Pillar bag support
WO2000014384A1 (en) * 1998-09-03 2000-03-16 Alethea Rosalind Melanie Hall Mine support
WO2008087536A1 (en) * 2007-01-18 2008-07-24 Skarboevig Nils Mittet A grout bag type of underground support
US8070394B2 (en) * 2007-01-18 2011-12-06 Nils Mittet Skarbovig Versatile grout bag type of underground support
US8246276B2 (en) * 2010-07-09 2012-08-21 Abc Industries, Inc. Pumpable crib bag assembly and method of installation
CN103026000A (en) * 2010-04-22 2013-04-03 美康公司 Pumpable support with cladding
US20140314490A1 (en) * 2013-04-19 2014-10-23 Abc Industries, Inc. Pumpable mine ventilation structure
CN107676131A (en) * 2017-11-10 2018-02-09 缪协兴 A kind of solid waste packs filling coal mining method

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB862210A (en) * 1956-04-25 1961-03-01 Karl Balthasar Mine roof supports
GB2091314A (en) * 1980-12-30 1982-07-28 Elliot Gordon Packing Means for Underground Passageways

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB862210A (en) * 1956-04-25 1961-03-01 Karl Balthasar Mine roof supports
GB2091314A (en) * 1980-12-30 1982-07-28 Elliot Gordon Packing Means for Underground Passageways

Cited By (33)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2154769A (en) * 1984-02-28 1985-09-11 Gandlake Software Ltd Computer software protection
GB2169630A (en) * 1985-01-16 1986-07-16 H L & H Timber Products Mat pack brick
EP0191570A3 (en) * 1985-01-29 1987-02-04 Alethea Rosalind Melanie Hall Support member
EP0191570A2 (en) * 1985-01-29 1986-08-20 Alethea Rosalind Melanie Hall Support member
DE3602776A1 (en) * 1986-01-30 1987-08-06 Ketterer Klaus Method of securing the roadside edges in longwall face mining, and pack of construction material
GB2186607A (en) * 1986-02-14 1987-08-19 British Reinforced Concrete Eng Co Ltd Mine roof support pack for cementitious filling
GB2186607B (en) * 1986-02-14 1990-03-28 British Reinforced Concrete Eng Co Ltd Supporting underground workings
EP0277670A1 (en) * 1987-01-21 1988-08-10 Digging Trading Company, N.V. Ground barrier
US4983077A (en) * 1987-08-26 1991-01-08 Gebhardt & Koenig-Gesteins- Und Tiefbau Gmbh Method and an apparatus for producing fabric-reinforced lining supports or slender supporting structural units
WO1990015224A1 (en) * 1989-05-30 1990-12-13 Fosroc International Limited Load support
US5143340A (en) * 1989-05-30 1992-09-01 Fosroc International Limited Load support
GB2250526A (en) * 1989-05-30 1992-06-10 Fosroc International Ltd Load support
GB2250526B (en) * 1989-05-30 1993-02-24 Fosroc International Ltd Load support
GB2236089B (en) * 1989-10-19 1991-08-21 Flexadux Plastics Ltd Cement mixing nozzle
GB2236089A (en) * 1989-10-19 1991-03-27 Flexadux Plastics Ltd Containment bags used in monolithic packing system etc
GB2245014A (en) * 1990-06-13 1991-12-18 Amco Plastics Ltd Means for filling a void
GB2245014B (en) * 1990-06-13 1994-09-28 Amco Plastics Ltd Method of and means for filling a void
GB2296517A (en) * 1994-12-27 1996-07-03 H L & H Timber Prod Prestress grout bag
GB2296517B (en) * 1994-12-27 1998-04-15 H L & H Timber Prod Prestress grout bag having a filler valve
WO1999009299A1 (en) * 1997-08-18 1999-02-25 Fosroc International Limited Pillar bag support
AU739209B2 (en) * 1997-08-18 2001-10-04 Fosroc International Limited Pillar bag support
WO2000014384A1 (en) * 1998-09-03 2000-03-16 Alethea Rosalind Melanie Hall Mine support
AU757770B2 (en) * 1998-09-03 2003-03-06 Alethea Rosalind Melanie Hall Mine support
US6558085B1 (en) 1998-09-03 2003-05-06 Alethea Rosalind Melanie Hall Mine support and method of forming the same
WO2008087536A1 (en) * 2007-01-18 2008-07-24 Skarboevig Nils Mittet A grout bag type of underground support
US8070394B2 (en) * 2007-01-18 2011-12-06 Nils Mittet Skarbovig Versatile grout bag type of underground support
CN103026000A (en) * 2010-04-22 2013-04-03 美康公司 Pumpable support with cladding
CN103026000B (en) * 2010-04-22 2017-07-21 美康公司 Pumpable supporting with covering
US8246276B2 (en) * 2010-07-09 2012-08-21 Abc Industries, Inc. Pumpable crib bag assembly and method of installation
AU2011201579B2 (en) * 2010-07-09 2014-07-10 Abc Industries, Inc. Pumpable crib bag assembly and method of installation
US20140314490A1 (en) * 2013-04-19 2014-10-23 Abc Industries, Inc. Pumpable mine ventilation structure
US9022689B2 (en) * 2013-04-19 2015-05-05 Heintzmann Corporation Pumpable mine ventilation structure
CN107676131A (en) * 2017-11-10 2018-02-09 缪协兴 A kind of solid waste packs filling coal mining method

Also Published As

Publication number Publication date
GB2131850B (en) 1986-09-10
GB8332534D0 (en) 1984-01-11

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