GB2043742A - Strata support in mines and tunnels - Google Patents

Abstract

Mine-roof support arch cladding comprises sheeting (30, 32) constructed to interlocate with arches and fit together overlappingly with interengagement against relative displacement. Specifically, the sheeting is corrugated to fit over arches and/or adjacent spans of sheeting. Also, a crown sheeting part (32) has tongue and socket interengagement (34, 36) with side sheeting parts (30) so the latter can be hung on the former. Only one arch per sheeting span is required and may be near one end thereof with the other end supporting overlapped by the next span of sheeting. <IMAGE>

Description

SPECIFICATION Strata support in mines and tunnels The invention relates to strata support particularly, but not necessarily exclusively, in mining and in relation to tunnels, such as mine roadways.

In mining, roadways providing access for personnel and equipment to mine faces, and transfer out of mineral or debris, are usually supported against strata collapse by arches, typically of multi-part reinforcing steel joist construction. Component parts, e.g. side and crown parts are usually connected together end-to-end by fishplates. The conflicting requirements of height adjustability and high resistance to strata collapse are usually met by so-called "slow-yield" telescopic seatings employing steel plate formed to a generally M-shaped section that, centrally, receives and locates the end of a side component part and, spaced therefrom, straddles edges of a hollow base so as to require drawing of side walls of the plate over those latter edges on yielding. In-filling between arches has most often been by way of metal or wood plates, slats, boards, planks or the like.

Several disadvantages arise from such arch support provisions, notably slow erection times and susceptibility to inevitable deterioration of parts, for example telescoping parts and their seating plates, and the infilling between arches. This invention and that of a companion application are directed to alleviating these disadvantages to substantial practical benefit.

Specifically, herein attention is directed to avoidance of problems arising from infilling. To this end, we propose the use of cladding in the form of sheeting preformed and sized to interlocate with, preferably fit over, an arch or arches, and adapted to fit together overlappingly and interengage against relative displacement in at least one direction. In referring to arches we have, of course, in mind that their shape will be dictated by what is to be supported.

The interengagement is preferably both as to localised complementary formations, such as of hook-and-eye type, and as to larger scale formations, such as channels or lips-and-grooves. The localised formations may serve the purpose of inter-coupling overlapped edge portions of side and crown sheeting parts that together making up a desired span of cladding between at least two spaced arches and so that they cannot slide apart.

Then, the channel or lip-and-groove type of formations would run over the arches and serve for interlocating sheeting of adjacent, side-overlapped, spans of cladding.

However, if desired, the side and crown sheets could be located by interlocating channels or lipsand-grooves over the span of the arch and adjacent spans located by localised complementary formations. There is however, advantage in avoiding interengaging formations right across the sheeting transversely of the arch span as that could require localised relief thereof to accommodate the arches themselves.

For preference, side sheeting parts interlocate with crown sheeting parts so that the former can be hung from the latter.

In general, embodiments of the invention allow of self-locating fitment of cladding over arches that are subsequently raised against the roof for support purposes and thereby substantially reduce erection and finishing time and effort.

One embodiment of the invention will now be specifically described, by way of example, with reference to the accompanying drawing, in which:- Figure 1 shows part of an arch in assembled and raised or set conditions; Figure 2 shows ends of cladding sheeting parts to interfit together; Figure 3 is a detail of the interfitment of Figure 2; and Figure 4 is a section showing relationships between cladding and arches, and between adjacent spans of cladding.

In Figure 1, an arch 10 comprises side and crown parts 12, 14 of I-section reinforcing steel joisting fishplated together at 16. An adjustable extension device for the arch side parts is indicated at 18 with a hinged or universal connection 20 to a ground engager or anchorage 22. Dashed references indicate the arch 10 after assembly and before extension but offset from its connection 10.

Referring to Figures 2 to 4 for the cladding embodying this invention, side and crown sheets 30, 32 are shown (Figure 2) for end-to-end location by means of an overlap to accomplish interfitting of localised complementary formations 34,36. As shown, both are pressed out tongues, those (34) of the side sheets being of generally triangular or truncated triangular shape and those (36) of the crown sheets being generally broader, in fact rectangular, to permit the former to pass over the edge from which the latter is pressed out hook-and-eye fashion (see Figure 3). Obviously, the tongue formations 36 could, for interlocation purposes only, be omitted in favour of a hole or slot.

It will also be noted that the cladding sheets 30,32 are of corrugated form with a pitch that accommodates the arch joisting (see Figure 4). Also, as shown, the complementary pressed out formations 34, 36 are in those channels that at sides of the sheeting are occupied by the arch joisting. This will result in advantageous pressing down of the tongues 34,36 by the joists on raising the arches to the roof and/or on compression by downward roof forces. Then, the tongues 36 will effectively close on and lock to the tongues 34. If desired, such tongue formations may be provided only in arch joist occupied channels thus avoiding any tongue protrusion at all, though that is unlikely to be much of a problem given that they will be at recessed levels viewed from within the arch.

Figure 4 also shows that the illustrated corrugated sheeting panels are conveniently interlocated side by-side by overlapping their corrugations, without necessarily having more than one direct arch sup port for each sheet width.

Reverting now to Figures 2 and 3, the crown sheet ing as illustrated will fit inside the side sheet on their interlocking overlap. However, the opposite arrangement is equally feasible and could be used in practice, despite the obvious advantages of first placing in situ the crown sheeting and then attaching the side sheeting housing to-hang therefrom by the hook-and-tongue type coupling.

The corrugated cladding will, itself, provide a substantial degree of strata support, for an excess of what can be achieved using in-filling plates or boards.

Possibly, cladding hereof could interfit edge-on into arches of appropriate section.

Claims (16)

1. Cladding of mine-roof support arches, comprising sheeting preformed and sized to interlocate with an arch or arches and adapted for sheeting parts to fit together overlappingly and interengage against relative displacement in at least one direction.

2. Cladding according to claim 1, wherein the sheeting fits over said arch or arches.

3. Cladding according to claim 2, wherein said sheeting comprises arch crown and side parts having, in edge portions that overlap each other on fitting over an arch or arches, complementary formations that serve to prevent those crown and side parts being slid away from each other.

4. Cladding according to claim 3, wherein said complementary formations allow the side parts to be hung from the crown parts.

5. Cladding according to claim 4, wherein said complementary formations comprise downwardly directed tongues on the side parts and holes or slots in the crown parts.

6. Cladding according to claim 5, wherein said tongues comprise pressings out of the side parts.

7. Cladding according to claim 5 or claim 6, wherein said holes or slots are left by tongues pressed out of the crown parts.

8. Cladding according to claim 7, wherein the side part tongues are generally triangular and the crown part tongues are generally rectangular.

9. Cladding according to any preceding claim, wherein said or further complementary formations restrain overlapped adjacent spans of cladding from movement away from each other.

10. Cladding according to claim 9 with claim 3, wherein said further complementary formations run in a direction over said arches.

11. Cladding according to claim 10, wherein said further complementary formations comprise channels.

12. Cladding according to claim 11, wherein said sheeting is corrugated to provide said channels.

13. Cladding according to claim 10, wherein at least one corrugated channel accommodates a said arch.

14. Cladding according to any preceding claim, having one arch per span of cladding.

15. Cladding according to claim 14 with claim 10, wherein said further complementary formations are adjacent to a said arch.

16. Cladding of mine-roof support arches substantially as herein described with reference to and as shown in the accompanying drawing.