AU749929B2

AU749929B2 - Cable line stopping

Info

Publication number: AU749929B2
Application number: AU33992/99A
Authority: AU
Inventors: Kevin Gary Rohl; Raymond Gordon Truloff
Original assignee: CERVETTO COURTICE SOLICITORS
Current assignee: CERVETTO COURTICE SOLICITORS
Priority date: 1998-04-27
Filing date: 1999-04-22
Publication date: 2002-07-04
Anticipated expiration: 2019-04-22
Also published as: AU3399299A

Description

1 CABLE LINE STOPPING FIELD OF THE INVENTION This invention relates to an improved method of constructing a stopping, particularly for use in underground mining.

BACKGROUND TO THE INVENTION Stopping is the process of sealing, sealing off, quarantining, closing or restricting access to or from an area.

Stoppings have a number of purposes. They are used for sealing roadways.

They are used for the segmentation of belt roads. They are used for the sealing of mine areas. They are used for the control of ventilation air. They are used for overcasts.

There have been many forms of stoppings used, however, the manufacture of those conventional stoppings has involved traditional means where the stopping is generally constructed using traditional building methods and traditional building 1 5 materials. In this specification, those stoppings will be referred to as "traditional S.stoppings".

The conventional method of constructing a traditional stopping is to prepare *the site of the stopping by removing and levelling or straightening the area in which the stopping is to be placed, placing a foundation or other support and constructing a stopping from concrete, bricks, metal or other material.

The traditional manufacturing processes used in the construction of existing stoppings are labour intensive and expensive.

spnThere are a number of problems and drawbacks with conventional stoppings. They include:- The materials used are expensive. The materials generally used in conventional stoppings comprise concrete, bricks, steel and wood. The invention ooooo uses mining anchor bolts, wire rope, fittings to attach the wire rope to the anchor bolts, mesh and a flexible membrane material.

The traditional methods requires building expertise to quite a high standard.

The area to be stopped must be accurately measured and the foundations accurately laid and the material used in the stopping measured and cut to a high degree of accuracy. The invention does not require particular accuracy in its construction.

The anchor bolts do not have to be accurately placed. The wire rope length is not critical as it can be adjusted by wire rope clamps and by turn buckles.

Traditional stoppings do not allow for the easy removal of the stopping.

Once the traditional stopping is in place, the complete structure normally has to be demolished to allow the passage of vehicles or any amendment. With the invention, movement through the stopping is much easier and cheaper and quicker by virtue of the fact that the stopping can be easily, partially or fully removed by undoing the anchor nuts on the bolts, moving the stopping and replacing it when required.

The traditional stopping is generally inflexible. This a particular problem in high roof heave or floor heave areas where there is significant movement of the surfaces intended to be stopped. When traditional stoppings are used in these areas, the integrity and strength of the stopping is damaged by the movement or, 15 alternatively, the sealing qualities in the event of a heave, which increases the area to be stopped, damages the sealing qualities of the stopping.

Traditional stoppings, particularly those used in high floor heave areas lose strength once the construction has been damaged. The invented stopping has a high rate of flexibility and so is not as sensitive to movement as the traditional stopping.

The inherent flexibility of the invention combined with its strength allows it to withstand forces without sustaining damage much more so than the conventional stopping. A conventional brick wall stopping, if struck by a vehicle, can collapse or be severely damaged. The invented stopping has a much higher 25 ability to absorb such impacts than conventional stopping.

The invented stopping is able to withstand sudden changes in air pressure or explosions more so than conventional stoppings.

Traditional stoppings utilise bulky and heavy materials. There is a considerable cost component involved in conveying the mortar, bricks, timber and other equipment required to construct the conventional stopping. The materials required for the construction of the invention are much easier to transport. The wire rope used normally comes on spools. The mesh or weave can be taken to the site in a rolled up form. The membrane coating is prior to application, a liquid which is transported in a container.

OUTLINE OF THE INVENTION The short comings listed in the previous paragraph and the short comings generally evident in traditional stoppings, are overcome by the present invention which utilises commonly used and proprietary available materials constructed in such a manner that the resulting structure has the necessary rigidity in all dimensions required, has the sealing qualities required of a stopping, is robust enough to comply with mining use and is much more flexible, particularly when subjected to vertical movements of the area intended to be stopped in high floor and roof heave areas.

In one aspect therefore, there is provided a mine stopping of flexible membrane material laid while liquid and allowed to harden comprising a series of 15 dividers anchored in said mine and dividing said stopping into panels of predetermined outline, said dividers comprising wire rope anchored by anchor bolts, said panels being formed from a layer of mesh supported by the dividers with said flexible membrane material being laid while liquid on the mesh, said dividers having tensioning means set at a predetermined tension and serving as means for aiding in the anchoring of the stopping and in maintaining the stopping in position while permitting extension of the stopping within predetermined limits as set by said tensioning means.

~Typically, the mine stopping stops an opening in a mine, the opening having a contour, the anchor bolts being located at spaced intervals so that wire rope 25 follows the contour of the opening.

Where the mine stopping stops an opening in a mine in a region of high floor or roof heave, at least one of said dividers extending in the direction of floor or roof heave is loosely tensioned to account for anticipated floor or roof heave. In this embodiment the stopping adjacent the loosely tensioned divider is displaced laterally out of an imaginary plane extending between opposing anchor bolts.

Typically, the mesh is attached to the dividers at spaced intervals by mechanical means prior to application of the liquid membrane material.

Typically, the mine stopping stops an opening in a mine, the opening having a contour line along the mine wall defined by an imaginary line interconnecting the anchor bolts, the mesh having a peripheral edge following the contour and being attached at spaced intervals to the wall.

The membrane material may be laid on one the mesh opposite the dividers, on both sides of the mesh or on the same side as the dividers.

In some circumstances a strengthening construction supplements the anchor bolts in the anchoring of the stopping and in maintaining the stopping in position, the strengthening construction comprising at least one rigid girder rigidly anchored at opposite ends in the mine wall and extending across the stopping and serving as an intermediate anchor site for at least some of said dividers. Preferably, at least some of said dividers are non-vertical and the strengthening construction comprises 15 at least one rigid girder anchored at opposite ends in the mine and extending across the stopping and across the non-vertical dividers and serving as an intermediate anchor site for one end of each of the non-vertical dividers.

Where the mine stopping is non-straight it typically includes a first generally planar stopping portion, a second generally planar stopping portion and an intermediate anchoring girder between the portions, dividers of the first portion having one end anchored by anchor bolts anchored in a first mine wall section and opposite ends thereof anchored via the intermediate anchoring girder, dividers of the second portion having one end anchored by anchor bolts anchored in a second mine wall section and opposite ends thereof being anchored via the intermediate girder, the stopping portions generally occupying planes defined by imaginary planes extending to and intersecting at the girder.

S"Preferably the mine stopping is retractable by disconnecting selected dividers so the stopping may be retracted to alter ventilation or allow vehicles or personnel to pass.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 shows an area of mine working that requires a vertical stopping Figure 2 shows the mine working of Figure 1 with anchor bolts placed in the plane required to be sealed off; Figure 3 shows the detail of a typical attachment to locate wire rope so as to locate the wire rope near the surface which is required to be stopped; Figure 4 shows wire rope threaded through the various attachments; Figure 5 shows loosely tensioning the vertical wire ropes in situations of extreme floor or roof heave; Figures 6 shows a side elevation of a partially completed stopping the components of the stopping; Figure 7 shows a stopping inserted so that the membrane is horizontal; Figure 8 shows a stopping constructed with the assistance of an intermediate strengthening construction; Figure 9 shows a non-straight stopping viewed from a plan view; Figure 10 demonstrates the invention used in a typical long wall panel 15 development; Figure 11 shows the invention used in a situation allowing water pipes, air pipes, electricity, and similar utilities; and Figure 12 shows the membrane partially removed.

o METHOD OF PERFORMANCE Figure 1 shows an area of mine working that requires a stopping. In this case, the area 2 required to be stopped requires a vertical stopping.

Figure 2 shows that a number of anchor bolts 4 are placed in the plane ***required to be sealed off. Normal fully encapsulated chemical anchor bolts are utilised in Figure 2. Seven have been placed in the floor 6, seven have been placed 25 in the roof 8, three have been placed in the left vertical rib or side 10 and four have been placed in the right vertical rib or side 14. The placement, the dimensions and S"the specifications for the rock bolts would depend on the area to be stopped.

Figure 3 also shows the detail of a typical attachment to locate wire rope 16 of an appropriate dimension to that portion of the rock bolt which is visible so as to locate the wire rope near the surface which is required to be stopped. The form of the attachment is not critical. Proprietary manufactured attachments which are also detailed could be utilised.

Figure 4 shows wire rope threaded through the attachments 4. The configuration of the wire rope depends on the area to be stopped. In Figure 4, the illustration shown, a number of different lengths of wire rope have been utilised.

The number of different lengths of wire rope vary with the construction. In some instances, one length of wire rope could be utilised, much in the way that one length of material is used for stringing a tennis racquet. In the case of Figure 4, multiple pieces of wire rope have been used which have been attached to proprietary turn buckles 18 by conventional means.

The bolts are placed so that the wire rope follows the contour of the surface to be sealed inso much as is possible by tightening the nuts 20 on the rock bolts.

The wire ropes are tensioned by tightening the turn buckles. Figure 4 shows the wire ropes in a tensioned position.

S 15 Other means of tensioning the wire rope could be utilised including adjustable eye bolts, the tensioning of the wire ropes by deflection towards each other, the use of a mechanical tensioning device in conjunction with wire rope clamps 22 and other similar methods.

In areas of extreme floor or roof heave, the ability of the stopping to take up the altered area is obtained by loosely tensioning the vertical wire ropes as is shown in Figure Afterthewire ropes are tensioned, surface material 24 is attached to the wire ropes to form a surface to which a flexible membrane will adhere. In underground mining situations, "brattice", which is a non-static proprietary weave, could be used. Other mesh such as "tecrete" mesh or shade cloth or similar material could be used. In this specification whether mesh or weave or other material is used, it iwill be referred to as "mesh".

The mesh is affixed to the wire ropes by normal mechanical means such as zip ties 26, tie wire, U bolts or other similar fastenings depending on the type of mesh used.

The mesh is trimmed to size to fit the opening required to be stopped. To reduce the area required to be sealed and to strengthen the mesh, smaller fasteners can be used to directly attach the mesh to the wall of the area required to be sealed.

Once the mesh is cut to size, an elastic membrane coating is applied to the mesh. The proprietary compound "master seal" 800A or similar membrane would be applied to either one or both sides of the mesh.

The elastic membrane coating would be applied by spraying or by manual application with brush, roller or trowel.

Figures 6 shows a side elevation of the stopping showing detail of the anchor bolts and nuts, the wire rope, the wire rope to anchor bolt attachments, the wire rope tensioning device, the mesh, the attachments of the mesh to the wire rope and the elastic coating 28 after having been applied.

It will be realised that the stopping is not restricted to use in vertical situations as shown in Figure 1 nor in relation to the cross section of the area as 15 shown in those diagrams. The stopping can be used in any plane and to stop any shaped hole. Figure 7, for example, shows a stopping inserted so that the elastic membrane is horizontal. It could be used in a situation to protect workers from S•suffering injury from falling rocks or debris 30. The elastic membrane would °restrain the smaller debris while the wire rope would restrain the larger objects and the invention would still have the elasticity that a conventional barrier would not have. The construction of the stopping in this horizontal situation shown would be very much easier than a conventional stopping.

Figure 8 shows a stopping constructed in a situation where the area to be covered would place an unacceptable force on the rock bolts without the assistance 25 of a strengthening construction. In the figure shown, a steel I section girder 32 of "appropriate dimensions has been placed and secured in a vertical plane in the concrete. The wire rope on the rib line has been attached to the girder as shown.

By utilising this means the invention can be utilised in almost unlimited lengths.

Figure 9 shows a stopping constructed in a situation where an angle is required in the stopping viewed from a plan view. In this case, the two separate angles of the Sstopping are attached to the section of I girder shown in the plan.

Figure 10 demonstrates the invention used in a typical long wall panel development.

Assume the long wall extraction sequence has extracted 110 metres of the block 36 before the first major fall occurs and the first only major consequent displacement of air. Stoppings 38 and 40 will take the major air displacement.

The retreating long wall face is 2.45 metres in width. It has a hard sandstone roof with 120-130 psi rating. Stoppings 38 and 40 remain as seal stoppings to force the intake air over the extracted long wall block (shown hatched in the drawing). A softer fragile roof (70-50 psi) will not leave the exposed roof suspended for an appreciable distance and no major air displacement will occur. The length of the long wall block 42 from the installation roadway 44 to the takeoff roadway 46 is 3000 metres. The height of the seam to be extracted is 3000 mm.

All cable line stoppings for panel development in long wall extraction are for air control in the intake and return roadway headings. The stoppings are not S 15 panel seals or long wall seals and their prime function is to ensure the efficient ventilation of the panel developments and the long wall extractions. I have found the advantages of the exemplified stoppings to be: 1. Labour efficiency in installation; 2. Portability; and 3. Minimal maintenance.

Figure 11 shows the invention used in a situation allowing water pipes 48 and air pipes 50 and electricity wire ropes and similar utilities. Figure 12 shows the membrane 28 partially removed which is required in situations to alter the ventilation of an area or to allow personnel or vehicles to pass through the stopping.

o 0 .o0.

Claims

1. A mine stopping of flexible membrane material laid while liquid and allowed to harden comprising a series of dividers anchored in said mine and dividing said stopping into panels of predetermined outline, said dividers comprising wire rope anchored by anchor bolts, said panels being formed from a layer of mesh supported by the dividers with said flexible membrane material being laid while liquid on the mesh, said dividers having tensioning means set at a predetermined tension and serving as means for aiding in the anchoring of the stopping and in maintaining the stopping in position while permitting extension of the stopping within predetermined limits as set by said tensioning means.

2. A mine stopping according to claim 1 wherein the mine stopping stops an opening in a mine, the opening having a contour, the anchor bolts being located at spaced intervals so that said wire rope follows the contour of the opening.

3. A mine stopping according to claim 1 wherein the mine stopping stops an opening in a mine in a region of high floor or roof heave and said wire rope includes at least one wire rope extending in a direction of floor or roof heave is loosely tensioned to account for anticipated floor or roof heave. A mine stopping according to claim 1 wherein the mesh is attached to the "wire rope at spaced intervals by mechanical means prior to application of the liquid membrane material. A mine stopping according to claim 1 wherein the mine stopping stops an opening in a mine wall, the opening having a contour line along the mine wall defined by an imaginary line interconnecting the anchor bolts, the mesh having a peripheral edge following the contour and being attached at spaced intervals to the wall.

6. A mine stopping according to claim 1 wherein said membrane material is laid on one side of the mesh opposite the wire rope.

7. A mine stopping according to claim 1 wherein said membrane material is laid on both sides of the mesh.

8. A mine stopping according to claim 1 wherein said membrane material is A laid on the same side of the mesh as said wire rope.

9. A mine stopping according to claim 1 for a mine wall opening wherein a strengthening construction supplements the anchor bolts in the anchoring of the stopping and in maintainingthe stopping in position, the strengthening construction comprising at least one rigid girder rigidly anchored at opposite ends in the mine wall and extending across the stopping and serving as an intermediate anchor site for at least some of said wire rope. A mine stopping according to claim 1 wherein at least some of said wire rope comprises non-vertical wire ropes and further includes a strengthening construction supplementing the anchor bolts and wire rope in the anchoring of the stopping and in maintaining the stopping in position, the strengthening construction comprising at least one rigid girder anchored at opposite ends in the mine and extending across the stopping and across the non-vertical ropes and serving as an intermediate anchor site for one end of each of the non-vertical wire ropes.

11. A mine stopping according to claim 1 wherein said mine stopping is non- straight and includes a first generally planar stopping portion, a second generally planar stopping portion and an intermediate anchoring girder between the portions, :°dividers of the first portion having one end anchored by anchor bolts anchored in a first mine wall section and opposite ends thereof anchored via the intermediate anchoring girder, dividers of the second portion having one end anchored by anchor bolts anchored in a second mine wall section and opposite ends thereof being anchored via the intermediate girder, the stopping portions generally occupying planes defined by imaginary planes extending to and intersecting at the *C girder.

12. A mine stopping according to claim 1 wherein said mine stopping is retractable by disconnecting wire rope from anchor bolts so the stopping may be retracted to alter ventilation or allow vehicles or personnel to pass. °13. A mine stopping according to claim 1 wherein the mine stopping stops an opening in a mine, the opening having a contour, the anchor bolts being located at spaced intervals so that wire rope follows the contour of the opening, said dividers including at least one wire rope extending in a direction of anticipated o go ego .oo 11 floor or roof heave and being loosely tensioned to account for anticipated floor or roof heave.

14. A mine stopping according to claim 1 wherein the mine stopping stops an opening in a mine, the opening having a contour, the anchor bolts being located at spaced intervals so that wire rope follows the contour of the opening, the mesh being attached to the dividers at spaced intervals by mechanical means prior to application of the liquid membrane material. A mine stopping according to claim 1 wherein the mine stopping stops an opening in a mine wall, the opening having a contour, the anchor bolts being located at spaced intervals so that wire rope follows the contour of the opening, the contour being defined by an imaginary line interconnecting the anchor bolts, the mesh having a peripheral edge following the contour and being attached at spaced intervals to the wall.

16. A mine stopping according to claim 1 wherein the mine stopping stops an opening in a mine, the opening having a contour, the anchor bolts being located at spaced intervals so that wire rope follows the contour of the opening and wherein said membrane material is laid on one side of the mesh opposite the dividers.

17. A mine stopping according to claim 1 wherein the mine stopping stops an 20 opening in a mine, the opening having a contour, the anchor bolts being located at spaced intervals so that wire rope follows the contour of the opening and wherein said membrane material is laid on both sides of the mesh.

18. A mine stopping according to claim 1 wherein the mine stopping stops an opening in a mine, the opening having a contour, the anchor bolts being located at spaced intervals so that wire rope follows the contour of the opening and wherein said membrane material is laid on the same side of the mesh as said dividers.

19. A mine stopping according to claim 1 wherein the mine stopping stops an opening in a mine, the opening having a contour, the anchor bolts being located at spaced intervals so that wire rope follows the contour of the opening, a Sstrengthening construction supplementing the anchor bolts in the anchoring of the stopping and in maintaining the stopping in position, the strengthening construction comprising at least one rigid girder rigidly anchored at opposite ends in the mine wall and extending across the stopping and serving as an intermediate anchor site for at least some of said dividers.

20. A mine stopping according to claim 1 wherein the mine stopping stops an opening in a mine, the opening having a contour, the anchor bolts being located at spaced intervals so that wire rope follows the contour of the opening, at least some of said dividers being non-vertical and the stopping further includes a strengthening construction supplementing the anchor bolts and dividers in the anchoring of the stopping and in maintaining the stopping in position, the strengthening construction comprising at least one rigid girder anchored at opposite ends in the mine and extending across the stopping and across the non-vertical dividers and serving as an intermediate anchor site for one end of each of the non- vertical dividers.

21. A mine stopping according to claim 1 wherein the mine stopping stops an .opening in a mine, the opening having a contour, the anchor bolts being located at spaced intervals so that wire rope follows the contour of the opening, said mine stopping being non-straight and including a first generally planar stopping portion, a second generally planar stopping portion and an intermediate anchoring girder between the portions, dividers of the first portion having one end anchored by i. anchor bolts anchored in a first mine wall section and opposite ends thereof anchored via the intermediate anchoring girder, dividers of the second portion having one end anchored by anchor bolts anchored in a second mine wall section and opposite ends thereof being anchored via the intermediate girder, the stopping 25 portions generally occupying planes defined by imaginary planes extending to and intersecting at the girder.

22. A mine stopping according to claim 1 wherein the mine stopping stops an opening in a mine, the opening having a contour, the anchor bolts being located at spaced intervals so that wire rope follows the contour of the opening, said mine stopping being retractable by disconnecting dividers so the stopping may be retracted to alter ventilation or allow vehicles or personnel to pass. 13

23. A mine stopping according to claim 1 wherein the mine stopping stops an opening in a mine in a region of high floor or roof heave, at least one of said dividers extending in the direction of floor or roof heave is loosely tensioned to account for anticipated floor or roof heave, the stopping adjacent the loosely tensioned dividers being displaced laterally out of an imaginary plane extending between opposing anchor bolts of said loosely tensioned divider and the mesh being attached to the dividers at spaced intervals by mechanical means prior to application of the liquid membrane material.

24. A mine stopping according to claim 1 wherein the mine stopping stops an opening in a mine in a region of high floor or roof heave and at least one of said dividers extending in the direction of floor or roof heave is loosely tensioned to account for anticipated floor or roof heave, the stopping adjacent the loosely tensioned divider being displaced laterally out of an imaginary plane extending between opposing anchor bolts of said loosely tensioned divider and the opening having a contour line along the mine wall defined by an imaginary line interconnecting the anchor bolts, the mesh having a peripheral edge following the contour and being attached at spaced intervals to the wall. A mine stopping according to claim 1 wherein the mine stopping stops an opening in a mine in a region of high floor or roof heave, at least one of said dividers extending in the direction of floor or roof heave being loosely tensioned to account for anticipated floor or roof heave, said membrane material being laid on one side of the mesh opposite the dividers. :26. A mine stopping according to claim 1 wherein the mine stopping stops an opening in a mine in a region of high floor or roof heave, at least one of said 25 dividers extending in the direction of floor or roof heave being loosely tensioned to account for anticipated floor or roof heave, the stopping adjacent the loosely tensioned divider being displaced laterally out of an imaginary plane extending between opposing anchor bolts of said loosely tensioned divider, said membrane material being laid on both sides of the mesh.

27. A mine stopping according to claim 1 wherein the mine stopping stops an opening in a mine in a region of high floor or roof heave, at least one of said 14 dividers extending in the direction of floor or roof heave being loosely tensioned to account for anticipated floor or roof heave, the stopping adjacent the loosely tensioned divider being displaced laterally out of an imaginary plane extending between opposing anchor bolts of said loosely tensioned dividers, said membrane material being laid on the same side of the mesh as said dividers.

28. A mine stopping according to claim 1 wherein the mine stopping stops an opening in a mine in a region of high floor or roof heave, at least one of said dividers extending in the direction of floor or roof heave being loosely tensioned to account for anticipated floor or roof heave, the stopping adjacent the loosely tensioned divider being displaced laterally out of an imaginary plane extending between opposing anchor bolts of said loosely tensioned divider, a strengthening construction supplementing the anchor bolts in the anchoring of the stopping and in maintaining the stopping in position, the strengthening construction comprising at least one rigid girder rigidly anchored at opposite ends in the mine wall and extending across the stopping and serving as an intermediate anchor site for at least some of said dividers.

29. A mine stopping according to claim 1 wherein the mine stopping stops an opening in a mine in a region of high floor or roof heave, at least one of said dividers extending in the direction of floor or roof heave being loosely tensioned to account for anticipated floor or roof heave, the stopping adjacent the loosely *tensioned divider being displaced laterally out of an imaginary plane extending between opposing anchor bolts of said loosely tensioned divider, at least some of said dividers being non-vertical and further the stopping includes a strengthening construction supplementing the anchor bolts and dividers in the anchoring of the S 25 stopping and in maintaining the stopping in position, the strengthening construction comprising at least one rigid girder anchored at opposite ends in the mine and extending across the stopping and across the non-vertical dividers and serving as an intermediate anchor site for one end of each of the non-vertical dividers. A mine stopping according to claim 1 wherein the mine stopping stops an opening in a mine in a region of high floor or roof heave, at least one of said dividers extending in the direction of floor or roof heave being loosely tensioned to account for anticipated floor or roof heave, the stopping adjacent the loosely tensioned divider being displaced laterally out of an imaginary plane extending between opposing anchor bolts of said loosely tensioned divider, said mine stopping being non-straight and includes a first generally planar stopping portion, a second generally planar stopping portion and an intermediate anchoring girder between the portions, dividers of the first portion having one end anchored by anchor bolts anchored in a first mine wall section and opposite ends thereof anchored via the intermediate anchoring girder, wire ropes of the second portion having one end anchored by anchor bolts anchored in a second mine wall section and opposite ends thereof being anchored via the intermediate girder, the stopping portions generally occupying planes defined by imaginary planes extending to and intersecting at the girder.

31. A mine stopping according to claim 1 wherein the mine stopping stops an opening in a mine in a region of high floor or roof heave, at least one of said dividers extending in the direction of floor or roof heave being loosely tensioned V to account for anticipated floor or roof heave, the stopping adjacent the loosely tensioned divider being displaced laterally out of an imaginary plane extending between opposing anchor bolts of said loosely tensioned divider, said mine stopping being retractable by disconnecting selected dividers so the stopping may be retracted to alter ventilation or allow vehicles or personnel to pass.

32. A mine stopping according to claim 1 wherein the mesh is attached to the *dividers at spaced intervals by mechanical means prior to application of the liquid membrane material, the mine stopping stops an opening in a mine wall, the opening having a contour line along the mine wall defined by an imaginary line 25 interconnecting the anchor bolts, the mesh having a peripheral edge following the contour and being attached at spaced intervals to the wall.

33. A mine stopping according to claim 1 wherein the mesh is attached to the dividers at spaced intervals by mechanical means prior to application of the liquid membrane material, said membrane material being laid on one side of the mesh opposite the dividers. 16

34. A mine stopping according to claim 1 wherein the mesh is attached to the dividers at spaced intervals by mechanical means prior to application of the liquid membrane material, said membrane material being laid on both sides of the mesh. A mine stopping according to claim 1 wherein the mesh is attached to the dividers at spaced intervals by mechanical means prior to application of the liquid membrane material, said membrane material being laid on the same side of the mesh as said dividers.

36. A mine stopping according to claim 1 wherein the mesh is attached to the dividers at spaced intervals by mechanical means prior to application of the liquid membrane material and a strengthening construction supplements the anchor bolts in the anchoring of the stopping and in maintaining the stopping in position, the strengthening construction comprising at least one rigid girder rigidly anchored at opposite ends in the mine wall and extending across the stopping and serving as an S* intermediate anchor site for at least some of said dividers. 15 37. A mine stopping according to claim 1 wherein the mesh is attached to the o* dividers at spaced intervals by mechanical means prior to application of the liquid membrane material and at least some of said dividers are non-vertical and further includes a strengthening construction supplementing the anchor bolts and dividers in the anchoring of the stopping and in maintaining the stopping in position, the strengthening construction comprising at least one rigid girder anchored at opposite ends in the mine and extending across the stopping and across the non-vertical dividers and serving as an intermediate anchor site for one end of each of the non- vertical dividers.

38. A mine stopping according to claim 1 wherein the mesh is attached to the 25 dividers at spaced intervals by mechanical means prior to application of the liquid membrane material and said mine stopping is non-straight and includes a first generally planar stopping portion, a second generally planar stopping portion and an intermediate anchoring girder between the portions, dividers of the first portion having one end anchored by anchor bolts anchored in a first mine wall section and opposite ends thereof anchored via the intermediate anchoring girder, dividers of the second portion having one end anchored by anchor bolts anchored in a second a 17 mine wall section and opposite ends thereof being anchored via the intermediate girder, the stopping portions generally occupying planes defined by imaginary planes extending to and intersecting at the girder.

39. A mine stopping according to claim 1 wherein the mesh is attached to the dividers at spaced intervals by mechanical means prior to application of the liquid membrane material and said mine stopping is retractable by disconnecting selected dividers so the stopping may be retracted to alter ventilation or allow vehicles or personnel to pass. A mine stopping according to claim 1 wherein the mine stopping stops an opening in a mine wall, the opening having a contour line along the mine wall defined by an imaginary line interconnecting the anchor bolts, the mesh having a peripheral edge following the contour and being attached at spaced intervals to the wall, said membrane material being laid on one side of the mesh opposite the dividers.

41. A mine stopping according to claim 1 wherein the mine stopping stops an opening in a mine wall, the opening having a contour line along the mine wall defined by an imaginary line interconnecting the anchor bolts, the mesh having a peripheral edge following the contour and being attached at spaced intervals to the wall, said membrane material being laid on both sides of the mesh.

42. A mine stopping according to claim 1 wherein the mine stopping stops an opening in a mine wall, the opening having a contour line along the mine wall defined by an imaginary line interconnecting the anchor bolts, the mesh having a peripheral edge following the contour and being attached at spaced intervals to the wall, said membrane material being laid on the same side of the mesh as said dividers.

43. A mine stopping according to claim 1 wherein the mine stopping stops an opening in a mine wall, the opening having a contour line along the mine wall defined by an imaginary line interconnecting the anchor bolts, the mesh having a peripheral edge following the contour and being attached at spaced intervals to the wall, a strengthening construction supplementing the anchor bolts in the anchoring of the stopping and in maintaining the stopping in position, the strengthening construction comprising at least one rigid girder rigidly anchored at opposite ends in the mine wall and extending across the stopping and serving as an intermediate anchor site for at least some of said dividers.

44. A mine stopping according to claim 1 wherein the mine stopping stops an opening in a mine wall, the opening having a contour line along the mine wall defined by an imaginary line interconnecting the anchor bolts, the mesh having a peripheral edge following the contour and being attached at spaced intervals to the wall, at least some of said divider being non-vertical and the stopping further includes a strengthening construction supplementing the anchor bolts and dividers in the anchoring of the stopping and in maintaining the stopping in position, the strengthening construction comprising at least one rigid girder anchored at opposite ends in the mine and extending across the stopping and across the non-vertical dividers and serving as an intermediate anchor site for one end of each of the non- S* vertical dividers. 15 45. A mine stopping according to claim 1 wherein the mine stopping stops an opening in a mine wall, the opening having a contour line along the mine wall defined by an imaginary line interconnecting the anchor bolts, the mesh having a peripheral edge following the contour and being attached at spaced intervals to the wall, said mine stopping being non-straight and includes a first generally planar stopping portion, a second generally planar stopping portion and an intermediate anchoring girder between the portions, dividers of the first portion having one end anchored by anchor bolts anchored in a first mine wall section and opposite ends thereof anchored via the intermediate anchoring girder, dividers of the second portion having one end anchored by anchor bolts anchored in a second mine wall 25 section and opposite ends thereof being anchored via the intermediate girder, the stopping portions generally occupying planes defined by imaginary planes extending to and intersecting at the girder.

46. A mine stopping according to claim 1 wherein said membrane material is laid on one side of the mesh opposite the dividers and a strengthening construction supplements the anchor bolts in the anchoring of the stopping and in maintaining the stopping in position, the strengthening construction comprising at least one rigid 19 girder rigidly anchored at opposite ends in the mine wall and extending across the stopping and serving as an intermediate anchor site for at least some of said dividers.

47. A mine stopping according to claim 1 wherein said membrane material is laid on one side of the mesh opposite the dividers and at least some of said dividers are non-vertical and further includes a strengthening construction supplementing the anchor bolts and dividers in the anchoring of the stopping and in maintaining the stopping in position, the strengthening construction comprising at least one rigid girder anchored at opposite ends in the mine and extending across the stopping and across the non-vertical dividers and serving as an intermediate anchor site for one end of each of the non-vertical dividers.

48. A mine stopping according to claim 1 wherein said membrane material is laid on one side of the mesh opposite the dividers and said mine stopping is non- straight and includes a first generally planar stopping portion, a second generally 15 planar stopping portion and an intermediate anchoring girder between the portions, dividers of the first portion having one end anchored by anchor bolts anchored in .a first mine wall section and opposite ends thereof anchored via the intermediate anchoring girder, dividers of the second portion having one end anchored by anchor bolts anchored in a second mine wall section and opposite ends thereof being anchored via the intermediate girder, the stopping portions generally .o occupying planes defined by imaginary planes extending to and intersecting at the girder. :49. A mine stopping according to claim 1 wherein said membrane material is laid on one side of the mesh opposite the dividers and said mine stopping is 25 retractable by disconnecting selected dividers so the stopping may be retracted to alter ventilation or allow vehicles or personnel to pass. A mine stopping according to claim 1 wherein said membrane material is laid on both sides of the mesh and a strengthening construction supplements the anchor bolts in the anchoring of the stopping and in maintaining the stopping in position, the strengthening construction comprising at least one rigid girder rigidly anchored at opposite ends in the mine wall and extending across the stopping and serving as an intermediate anchor site for at least some of said dividers.

51. A mine stopping according to claim 1 wherein said membrane material is laid on both sides of the mesh and at least some of said dividers are non-vertical and further includes a strengthening construction supplementing the anchor bolts and dividers in the anchoring of the stopping and in maintaining the stopping in position, the strengthening construction comprising at least one rigid girder anchored at opposite ends in the mine and extending across the stopping and across the non-vertical dividers and serving as an intermediate anchor site for one end of each of the non-vertical dividers.

52. A mine stopping according to claim 1 wherein said membrane material is laid on both sides of the mesh and said mine stopping is non-straight and includes a first generally planar stopping portion, a second generally planar stopping portion **and an intermediate anchoring girder between the portions, dividers of the first 15 portion having one end anchored by anchor bolts anchored in a first mine wall section and opposite ends thereof anchored via the intermediate anchoring girder, dividers of the second portion having one end anchored by anchor bolts anchored in a second mine wall section and opposite ends thereof being anchored via the intermediate girder, the stopping portions generally occupying planes defined by imaginary planes extending to and intersecting at the girder. Si. 53. A mine stopping according to claim 1 wherein said membrane material is laid on both sides of the mesh and said mine stopping is retractable by *disconnecting selected dividers so the stopping may be retracted to alter ventilation or allow vehicles or personnel to pass. 25 54. A mine stopping according to claim 1 wherein said membrane material is laid on the same side of the mesh as said dividers and a strengthening construction supplements the anchor bolts in the anchoring of the stopping and in maintaining the stopping in position, the strengthening construction comprising at least one rigid girder rigidly anchored at opposite ends in the mine wall and extending across the stopping and serving as an intermediate anchor site for at least some of said dividers. q 21 A mine stopping according to claim 1 wherein said membrane material is laid on the same side of the mesh as said dividers and at least some of said dividers are non-vertical and further includes a strengthening construction supplementing the anchor bolts and dividers in the anchoring of the stopping and in maintaining the stopping in position, the strengthening construction comprising at least one rigid girder anchored at opposite ends in the mine and extending across the stopping and across the non-vertical dividers and serving as an intermediate anchor site for one end of each of the non-vertical dividers.

56. A mine stopping according to claim 1 wherein said membrane material is laid on the same side of the mesh as said dividers and said mine stopping is non- straight and includes a first generally planar stopping portion, a second generally planar stopping portion and an intermediate anchoring girder between the portions, dividers of the first portion having one end anchored by anchor bolts anchored in S* a first mine wall section and opposite ends thereof anchored via the intermediate 15 anchoring girder, dividers of the second portion having one end anchored by anchor bolts anchored in a second mine wall section and opposite ends thereof being anchored via the intermediate girder, the stopping portions generally occupying planes defined by imaginary planes extending to and intersecting at the girder.

57. A mine stopping according to claim 1 wherein said membrane material is laid on the same side of the mesh as said dividers and said mine stopping is .retractable by disconnecting selected dividers so the stopping may be retracted to alter ventilation or allow vehicles or personnel to pass.

58. A mine stopping according to claim 1 for a mine wall opening wherein a 25 strengthening construction supplements the anchor bolts in the anchoring of the stopping and in maintaining the stopping in position, the strengthening construction comprising at least one rigid girder rigidly anchored at opposite ends in the mine wall and extending across the stopping and serving as an intermediate anchor site for at least some of said dividers, said mine stopping being retractable by disconnecting selected dividers so the stopping may be retracted to alter ventilation or allow vehicles or personnel to pass. T I V 22

59. A mine stopping according to claim 1 wherein said mine stopping is non- straight and includes a first generally planar stopping portion, a second generally planar stopping portion and an intermediate anchoring girder between the portions, dividers of the first portion having one end anchored by anchor bolts anchored in a first mine wall section and opposite ends thereof anchored via the intermediate anchoring girder, dividers of the second portion having one end anchored by anchor bolts anchored in a second mine wall section and opposite ends thereof being anchored via the intermediate girder, the stopping portions generally occupying planes defined by imaginary planes extending to and intersecting at the girder, said mine stopping being retractable by disconnecting selected dividers so the stopping may be retracted to alter ventilation or allow vehicles or personnel to pass. *see* o 0 .o. *o* *0