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WO2000036274A1 - Bloc de soutenement souterrain - Google Patents

Bloc de soutenement souterrain Download PDF

Info

Publication number
WO2000036274A1
WO2000036274A1 PCT/ZA1999/000138 ZA9900138W WO0036274A1 WO 2000036274 A1 WO2000036274 A1 WO 2000036274A1 ZA 9900138 W ZA9900138 W ZA 9900138W WO 0036274 A1 WO0036274 A1 WO 0036274A1
Authority
WO
WIPO (PCT)
Prior art keywords
support
elements
yielding
beams
components
Prior art date
Application number
PCT/ZA1999/000138
Other languages
English (en)
Inventor
Johann Smit
Petrus Nicolaas Erasmus
Original Assignee
Grinaker Construction Limited
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
Application filed by Grinaker Construction Limited filed Critical Grinaker Construction Limited
Priority to AU20605/00A priority Critical patent/AU2060500A/en
Publication of WO2000036274A1 publication Critical patent/WO2000036274A1/fr

Links

Classifications

    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D15/00—Props; Chocks, e.g. made of flexible containers filled with backfilling material
    • E21D15/005—Props; Chocks, e.g. made of flexible containers filled with backfilling material characterised by the material
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D11/00—Lining tunnels, galleries or other underground cavities, e.g. large underground chambers; Linings therefor; Making such linings in situ, e.g. by assembling
    • E21D11/04—Lining with building materials
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D15/00—Props; Chocks, e.g. made of flexible containers filled with backfilling material
    • E21D15/48—Chocks or the like

Definitions

  • This invention relates to a support pack of a type which is suitable for use in an underground location, and to a support component for use in a support pack of this type. More particularly the invention is concerned with a support structure which may be of a type referred to as a crib, or pack, suitable for use in an underground excavation wherein
  • the spacing between the roof or hanging wall and the floor or footwall is relatively large.
  • Substantial roof heights are encountered in certain mines such as underground coal mines. Supports which have been developed for other applications, for example
  • a support should exhibit active load generation capabilities of at least approximately 50
  • the support structure should also be of a nature which, at least to the extent possible, allows for lateral movement between the roof and the floor without significant adverse effects.
  • the strata from which coal or any other desired ore is excavated are often relatively soft
  • excavation heights which may be encountered in coal mines the slendemess ratio of an elongate support may be such that it will fail catastrophically under load i.e. it will buckle
  • each layer in this type of support may call for four or more blocks and this, apart from being relatively expensive, is also labour intensive to erect.
  • Another disadvantage is that the support structure can fail under shear load conditions.
  • roof is filled with timber to provide a degree of preloading.
  • the invention provides in the first instance a support component which includes a beam
  • the yielding elements may be located at any convenient locations on the beam member
  • the elements may be weaker in compressive strength than the beam. Thus, when the
  • the elements may
  • the elements and the beam may be provided in kit form, e.g. to be assembled on site.
  • the elements may be engaged with the beam in any appropriate way.
  • the elements may be engaged with the beam in any appropriate way.
  • the beam may be engaged with the beam in any appropriate way.
  • elements and the beam may have inter-engaging formations or the elements may be fixed to the beam using straps or suitable fasteners.
  • the elements may also be adhesively
  • each yielding element is fixed to a beam using fastening
  • devices of any appropriate kind e.g. straps, sheet material or the like.
  • the beam may be of a first material and the elements may be of a second material.
  • the beam is made from timber of a first type and the elements are made from timber of a second type.
  • the beam is made from
  • the beam may otherwise be made from, or include, a steel bar, rod or pipe.
  • the beam includes relatively slender elongate components such as steel bars, rods or pipe then ends of the beam may be attached to yielding elements such as timber,
  • cementitious, plastic or polymeric blocks or be made from any other suitable material.
  • the beam and the elements are made from cementitious materials.
  • a lightweight cementitious aggregate or matrix which may, optionally, be reinforced by the addition of fibres or reinforcing components.
  • the beam may for example include longitudinally extending reinforcing rods, fibres, wires, etc.
  • the reinforcing components include mesh which may be metallic or of a suitable fibre.
  • the cementitious material may be of any appropriate hardness, density and composition,
  • each beam may be formed with locating formations and each yielding element may include a complementary formation which is engageable with
  • the invention also extends to a support pack which is formed from a plurality of support
  • each support component being of the aforementioned kind, the support
  • each column is defined by a stacked array of yielding elements alternating with ends of beams.
  • the support components may be arranged in successive pairs with the components in
  • each pair being substantially parallel to and spaced from each other, and with an upper pair of components overlying a lower pair of components and being displaced through 90°
  • each yielding element being sandwiched between ends of adjacent upper and lower beams thereby to defined the said columns.
  • the support components may be arranged overlying each other in a cross-shape, viewed in plan, and forming the four outer columns which, viewed from the side, are continuous
  • each column being defined by a respective said stacked array.
  • the pack may include a central column which includes a succession of gaps and bridging
  • the gaps may be air gaps or be formed by material which yields easily.
  • the invention also extends to a support pack which includes a plurality of beams
  • each yielding element being positioned between opposing ends of a
  • the gaps may be air gaps.
  • the invention further extends to a support pack which includes a plurality of spaced
  • Figure 8 illustrates a yielding element which may be incorporated in any of the components
  • Figure 9 illustrates a support structure, in the nature of a crib structure, which is erected
  • Figure 10 is perspective view of a support pack which is made from a plurality of
  • Figure 11 is a cross-sectional view through the pack of Figure 10 taken on the line x - x;
  • Figure 12 illustrates a further modification according to the invention
  • Figures 13A, 13B and 13C are graphs of load versus yield for different support packs of
  • FIG. 1 of the accompanying drawings illustrates a support component 10 according to
  • a first form of the invention which includes an elongate beam 12 and two yielding elements
  • the beam 12 is made from wood or concrete of any appropriate mix.
  • the concrete may for example be a lightweight cementitious mixture and include internal steel or other reinforcing 18.
  • the yielding elements 14 and 16 are blocks which, in plan and in this example, are square
  • the blocks could have any other suitable shape and could for example be
  • Each yielding element is made from a lightweight cementitious
  • length of side 300mm; height from 50 to 150mm.
  • cementitious composition which includes the following materials: cement;
  • suitable fillers e.g. sand or fly ash; extenders e.g. slagment or fly ash; air; steel or fibre
  • the density of the cementitious mixture used in each yielding element is in
  • the length of the beam is of the order of from 600mm to 1200mm and it is made from a cementitious mixture with the
  • cement e.g. sand or fly ash
  • suitable fillers e.g. sand or fly ash
  • extenders e.g. slagment
  • the density may range from 800kg/m 3 to
  • the strength of the beam is greater than the strength of the yielding element.
  • the reinforcing 18 may include steel rods or wires in any appropriate configuration.
  • the yielding elements 14 and 16 are adhesively fixed to the beam using any appropriate adhesive or grout.
  • Figure 2 illustrates a support component 20 according to a second form of the invention
  • each yielding element 14, 16 is formed with a respective downwardly facing
  • each yielding element may include a recessed formation 28 on its uppermost surface and the beam 12 may include a complementary projection 30
  • Figure 3 depicts a component 32 wherein use is made of plastic straps 34 to secure the
  • Figure 4 illustrates a support component 36 wherein a beam 12 is formed integrally with upstanding formations 38 at its opposed ends.
  • the formation 38 in effect, form the
  • yielding elements 14 and 16 which, in the other examples, are separately formed and then attached to the beam.
  • those sections which form the yielding elements 14 and 16 may have a different composition from the respective underlying sections designated 40. This may be achieved
  • Figure 5 illustrates a composite structure wherein a support component 42 includes an elongate steel rod, pipe or bar 44 with concrete blocks 46 and 48 attached to opposed
  • plastic sheet material may be any material that is attached to the blocks 46, 48 respectively, again making use of an adhesive, or straps of the kind shown in Figure 3, or in any other way.
  • plastic sheet material may be any material that is used to make use of an adhesive, or straps of the kind shown in Figure 3, or in any other way.
  • plastic sheet material may be any material that is used to make use of an adhesive, or straps of the kind shown in Figure 3, or in any other way.
  • plastic sheet material may be any other way.
  • Figure 6 shown a precast beam 12 which is made from a lightweight cementitious matrix of such a nature that a depression 49 can be stamped into the beam, once it has set,
  • the depression is shaped to receive a portion of a
  • yielding element 16 which, once located in the depression, is peripherally reinforced at its
  • a downwardly facing surface of an overlying beam, not shown, is similarly shaped to
  • Figure 7 illustrates a support component 50 according to a variation of the invention.
  • the beam 52 has a shallow U-shaped cross-section and yielding elements
  • the thickness 58 of an end section of a beam is the same as the thickness 60 of a yielding element.
  • the thickness 58 is greater than the
  • Figure 8 illustrates a yielding element 14 which is formed with a vertically extending passage 66 and which is internally reinforced by means of a steel mesh 68 which is bent into the form of a cage which is embedded in the cementitious matrix 70.
  • the mesh is
  • centrally positioned reinforcing could be used in place
  • Figure 9 illustrates a crib type support structure 74 which is constructed using support components of the kind shown in any of Figures 1 to 7.
  • a lowermost layer of the crib structure includes two components 10A and 10B respectively
  • An overlying pair of components 10C and 10D is placed over the components 10A and 10B.
  • the components 10C and 10D are parallel to and spaced from each other and are displaced through 90° relatively to the components 10A and 10B. Ends of the beams 12C and 12D lie respectively on the underlying yielding elements 14A
  • prestressing elements are inserted between the opposing surfaces of the structure 74 and
  • the overlying roof particularly at the four corners of the crib structure.
  • use may be made of grout filled bags which are pressurised in order to prestress the four columns of the crib structure.
  • the structure 74 in essence, provides four columnar type supports designated 76, 78, 80 and 82 respectively at its four respective corners.
  • Each columnar support includes a
  • each columnar support is anchored to adjacent columnar supports by means of the respective
  • the crib type structure thus provides columnar supports which are anchored to each other in a lateral sense. Problems which would otherwise arise with slendemess ratios are therefore eliminated or, at least, significantly reduced.
  • the area which is encompassed by the structure 74 is not filled with support material and the stability which is obtained by making use of a structure which extends in the horizontal plane is not accompanied by a corresponding increase in the quantity of material which is required.
  • the crib structure is hollow inside and the transversely extending tie members provide a "slatted" configuration which reduces the amount of material required for lateral stability and which does not
  • the height to width ratio of the crib is significantly impede the passage of air which might for example be required for ventilation purposes.
  • structure may be at least 4: 1.
  • the skeletal crib structure thus reduces material requirements.
  • Each yielding element may be designed to provide a required yield characteristic. This makes it possible to customise the yielding characteristic, within limits, to the actual installation conditions.
  • the support is active and provides continuous and controlled
  • the crib structure 74 may be constructed using any of the components shown in Figures 1 to 7. With the Figure 2 embodiment the formations 28 and 30 engage with
  • the yield characteristic of the structure 74 is determined by the characteristics of the yielding elements 14 and 16. These elements are designed to yield,
  • each yielding element may for example include cavities or recesses to promote yielding and may be reinforced using fibres or steel or any other material.
  • the beam 12 has a thickness 88.
  • Each element 14 and 16 has a thickness 90 which is greater than the thickness 88.
  • the beam has a width 92 (see Figure 10) and the elements 14 and 16 are spaced from one another by a distance 94.
  • the distance 94 is slightly greater than the width 92.
  • a plurality of the beams are used in the manner shown in Figure 10 to erect a cross- shaped support pack 96 in an underground excavation, not shown.
  • the pack
  • a component 10A is laid on a foot wall and, at a central region, the component 10A is then
  • Each element 98 is substantially similar to one of the elements 14 (or 16) and one element is located on one side of the component 10A, at a central
  • a second component 10B is then positioned on the elements 98, transversely to the component 10A.
  • the beam 12B of the second component passes between the elements 14A and 16A of the first component.
  • the beam 12B, where it traverses the beam 12A does not contact the beam 12A and a gap 100 (see Figure 11 ) is formed
  • a third component 10C is then laid over the components 10A and 10B and the beam 12C of the third component is directly superimposed over the beam 12A of the first component although it is separated therefrom by the elements 14A and 16A.
  • the beam 12C is
  • the support pack has a cross-shaped form
  • each of the columns 102 to 108 includes a stacked alternating array of end sections of beams 12 and yielding elements 14 and 16.
  • the central column 110 is defined by overlying central sections of transverse beams with gaps 100
  • the pack of Figure 10 has a number of significant benefits. It provides significant areal
  • the four principal load-bearing columns 102 to 108 can, to a significant extent, yield independently from each other but they are, nonetheless, linked to one
  • the central column 110 has a plurality of air gaps 100 in its height. Consequently when closure between the
  • the air gaps are firstly closed, in a vertical direction, before the central column 110 is capable of taking a significant compressive load.
  • the pack can yield in a manner which initially allows loading on the pack to be substantially uniformly distributed over the full area of the
  • Figure 4 shows the distance 94 materially greater than the width 92. Normally this is not the case and the distance 94 is only slightly greater than the width 92 with the result that the central column 110 effectively forms an inner boundary to the outer columns which significantly supports the outer columns.
  • Each beam 12, at its central region between the elements 14 and 16 could be made from a more yielding material than the outer sections of the beam or, alternatively, each beam
  • Figure 12 is a side view of a support component 120 according to another form of the
  • the component includes a beam 124 and yielding elements 126 and 128 respectively.
  • the beam is formed in its upper surface with recesses 130 and lower surfaces of the yielding elements include projections 132 which are complementary in shape to the recesses.
  • Upper surfaces of the yielding elements include recesses 134 which are substantially similar to the recesses 130.
  • lower surfaces of the beam include projections 136 which are similar to the projections 132.
  • yielding elements may be attached to the beam
  • the beams and the elements are formed with
  • the yield characteristic of a support pack of the invention can be designed to meet different requirements.
  • the yield characteristic can be altered by changing the materials from which the beams and the yielding elements are made.
  • Figures 13A, 13B and 13C illustrate three graphs of load versus yield, obtained for packs of the type shown in Figure 10.
  • the size of each air gap in the central column is essentially zero.
  • the air gaps are increased in size.
  • the entire pack yields with a substantially constant characteristic.
  • the pack yields with a first characteristic and then, as the air gaps close, the pack yields with a second characteristic.
  • the third case the third case,
  • the beam, and the yielding elements can be made from timber, or different types of timber, or any other suitable material. It is preferred though to make use of a lightweight cementitious mixture or mixtures, with suitable reinforcing, for this type of material enables the support components to be made with a consistent quality and with predictable and reliable characteristics.

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  • Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Structural Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Geology (AREA)
  • Architecture (AREA)
  • Mechanical Engineering (AREA)
  • Civil Engineering (AREA)
  • Rod-Shaped Construction Members (AREA)

Abstract

La présente invention concerne un composant de soutènement qui comprend une poutre et deux éléments coulissants espacés sur la poutre, utilisés dans un bloc de soutènement, lequel bloc est formé d'une pluralité de composants de soutènement. Ces composants de soutènement se superposent les uns sur les autres de façon à former au moins quatre poteaux extérieurs, chaque poteau étant défini par un réseau d'empilement d'éléments coulissants alternant avec des extrémités de poutre. Cette invention concerne aussi un bloc de soutènement qui comprend une pluralité de composants de soutènement, les poutres étant positionnées de façon à se superposer entre elles en forme de croix, formant ainsi un poteau central entouré par les quatre poteaux extérieurs
PCT/ZA1999/000138 1998-12-14 1999-12-14 Bloc de soutenement souterrain WO2000036274A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU20605/00A AU2060500A (en) 1998-12-14 1999-12-14 An underground support pack

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
ZA9811421 1998-12-14
ZA98/11421 1998-12-14
ZA994989 1999-08-04
ZA99/4989 1999-08-04

Publications (1)

Publication Number Publication Date
WO2000036274A1 true WO2000036274A1 (fr) 2000-06-22

Family

ID=27145092

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/ZA1999/000138 WO2000036274A1 (fr) 1998-12-14 1999-12-14 Bloc de soutenement souterrain

Country Status (2)

Country Link
AU (1) AU2060500A (fr)
WO (1) WO2000036274A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005059310A1 (fr) * 2003-12-18 2005-06-30 Grinaker-Lta Limited Element pour bloc de support
WO2005045193A3 (fr) * 2003-11-06 2005-07-14 Grinaker Lta Ltd Etai de soutenement et composant d'etai de soutenement

Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE599853C (de) * 1934-07-10 Heinz Boehler Wanderpfeiler im Bergwerksbetrieb
GB755362A (en) * 1953-05-19 1956-08-22 Becorit Grubenausbau Gmbh Improvements in or relating to chocks
DE1912668A1 (de) * 1969-03-13 1970-09-24 Helmut Huehnerbach Bauelement zur Errichtung von Stuetzpfeilern,insbesondere im bergbaulichen Untertagebetrieb
GB1348675A (en) * 1972-06-09 1974-03-20 British Ropes Ltd Structural load-bearing supports
GB1437453A (en) * 1973-03-31 1976-05-26 Siporex Ltd Mine chocks
GB1486195A (en) * 1973-12-12 1977-09-21 Laing & Son Ltd John Formulation for concrete or like water hardened mixed material
GB2137256A (en) * 1981-04-09 1984-10-03 Leuchars Hepburn Ltd Hunt Mine support
GB2145757A (en) * 1982-10-22 1985-04-03 H L & H Timber Products Mine support pack
GB2169630A (en) * 1985-01-16 1986-07-16 H L & H Timber Products Mat pack brick
US4628658A (en) * 1984-01-18 1986-12-16 H L & H Timber Products (Proprietary) Limited Support pack
GB2180866A (en) * 1985-09-26 1987-04-08 John Douglas Thompson Mine chock construction
GB2214950A (en) * 1988-02-02 1989-09-13 John Douglas Thompson Mine chockpieces of timber
US5435670A (en) * 1992-07-03 1995-07-25 Hl&H Timber Products (Proprietary) Limited Spacer assembly and method

Patent Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE599853C (de) * 1934-07-10 Heinz Boehler Wanderpfeiler im Bergwerksbetrieb
GB755362A (en) * 1953-05-19 1956-08-22 Becorit Grubenausbau Gmbh Improvements in or relating to chocks
DE1912668A1 (de) * 1969-03-13 1970-09-24 Helmut Huehnerbach Bauelement zur Errichtung von Stuetzpfeilern,insbesondere im bergbaulichen Untertagebetrieb
GB1348675A (en) * 1972-06-09 1974-03-20 British Ropes Ltd Structural load-bearing supports
GB1437453A (en) * 1973-03-31 1976-05-26 Siporex Ltd Mine chocks
GB1486195A (en) * 1973-12-12 1977-09-21 Laing & Son Ltd John Formulation for concrete or like water hardened mixed material
GB2137256A (en) * 1981-04-09 1984-10-03 Leuchars Hepburn Ltd Hunt Mine support
GB2145757A (en) * 1982-10-22 1985-04-03 H L & H Timber Products Mine support pack
US4628658A (en) * 1984-01-18 1986-12-16 H L & H Timber Products (Proprietary) Limited Support pack
GB2169630A (en) * 1985-01-16 1986-07-16 H L & H Timber Products Mat pack brick
GB2180866A (en) * 1985-09-26 1987-04-08 John Douglas Thompson Mine chock construction
GB2214950A (en) * 1988-02-02 1989-09-13 John Douglas Thompson Mine chockpieces of timber
US5435670A (en) * 1992-07-03 1995-07-25 Hl&H Timber Products (Proprietary) Limited Spacer assembly and method

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005045193A3 (fr) * 2003-11-06 2005-07-14 Grinaker Lta Ltd Etai de soutenement et composant d'etai de soutenement
WO2005059310A1 (fr) * 2003-12-18 2005-06-30 Grinaker-Lta Limited Element pour bloc de support

Also Published As

Publication number Publication date
AU2060500A (en) 2000-07-03

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