GB2240353A

GB2240353A - Underground support arch.

Info

Publication number: GB2240353A
Application number: GB9001692A
Authority: GB
Inventors: James Curtis Wilson
Original assignee: British Steel PLC
Current assignee: British Steel PLC
Priority date: 1990-01-25
Filing date: 1990-01-25
Publication date: 1991-07-31
Also published as: EP0439198A1; GB9001692D0

Description

41 t U nde _A r c h This invention relates supports underground,

particularly relates TH-section components.

to arches employed as eg. in mining, and more to arches embodying It is an object of this invention to provide, in an arch having non- curvilinear joints between at least some of its adjoining support members, a greater degree of flexibility in the shape and dimensions of the arch as required to suit these aspects in the tunnel hewn.

Accordingly, the present invention provides an arch comprising a plurality of elongate components constituting leg or roof beam members coupled together, at least one such coupling incorporating a chevron- shaped jointing component secured to adjoining members, characterised in that all said components constituting the arch are of uniform TH-section.

The chevron-shaped component may be produced by cutting a vee laterally through the bulk of an elongate TH-section member such as to leave only the 'nose' intact and then bending the member so as to close the vee, the mating surfaces then being welded together. Alternatively, two TH-section members may be mitred together to form the composite component, the mating surfaces either being welded together or to an intermediate plate sited between them.

The two arms of the chevron overlap the respective adjoining leg component and roof beam compollent and are secured thereto by bolts or straps.

OPR26/694 1 2 As mentioned the whole arch is constituted by TH-section components and enables great flexibility to be obtained where the arch configuration embodies a "square", ie. non-curvi linear, profile, those joints between adjacent TB-components remote from the the "square" joint(s) being constituted by overlapping sections bolted or strapped together to form either yielding or fixed supports.

In order that the invention may be fully understood, some embodiments thereof will now be described, by way of example, with reference to the accompanying drawings, in which:- Figure 1 schematically illustrates a typical arch profile embodying a "square" joint; Figure 2 illustrates a cross-section through a conventional TH-section component; Figures 3a and 3b illustrate the formation of one form of chevronshaped jointing component; and Figure 4 illustrates the formation of another form of such jointing component.

Referring to Figure 1 a "square" arch profile is shown comprising a THsection roof beam 1 (see Figure 2 for TH profile) with a curved leg support 2 on one side and a pair of curved leg supports 3,4 on the other side, this pair overlapping and being held together by yielding support clamps (not shown). Chevron-shaped jointing components 5,6 couple the roof beam to the leg supports.

OPR261694 2 i 1 1 1 i 3 Two convenient modes by which these components 5,6 may be produced are shown in Figures 3 and 4.

In Figure 3(a) a TH-section component 7 has a hole 8 drilled through it adjacent its bridge or nose piece and a mitre 9 is then cut into this component, terminating at 8. The two arms of the component are bent together as shown in Figure 3(b) to form the chevron, the mating surfaces then being welded together as shown at 10, on both the inside and the outside of the section.

Figure 4 shows an alternative form of chevron jointing component by which the two arms of the section are discrete and are separately mitred and brought together with a plate 11 between them. Welds are then laid down at the interface on each side of the plate ie. as depicted at 12 and 13. The advantage of this joint over that shown in Figures 3(a) and 3(b) is that no welding need be done inside the TH-section.

Although the invention has been described with particular reference to the accompanying drawings it is to be understood that various modifications may readily be made without departing from the scope of this invention. For example, a variety of other arch profiles may be formed embodying differently shaped leg and/or roof beam components consistent with the adoption of at least one chevron-shaped jointing component and the utilisation of TH-section components only.

OPR26/694 3

Claims

we claim: -

An arch comprising a plurality of elongate components constituting leg or roof beam members coupled together, at least one such coupling incorporating a che=n-shaped joirrting ccuponent secured to adjoining members, characterised in that all said components constituting the arch are of uniform M-section.
2. An arch according to claim 1, wherein the jointing component comprises two TH-section members mitred together.
3. An arch according to claim 2, wherein the mitred surfaces are welded to an intermediate plate sited between them.
An arch according to claim 2, wherein the mitred surfaces mate with one another and are welded together.
5. An arch according to claim 1, wherein the jointing component is constructed from a single elongate TH-section member in which a vee has been cut laterally therethrough such as to leave only the "noWl intact, the member being bent so as to close the vee the mating surfaces then being welded together.

An arch according to any one of claims 1 to 5, wherein the two arras of the chevron averlap the respective adjoining leg component and roof beam component and are secured thereto by bolts or straps.

i 7 1 i i i i il il 7. An arch substantially as herein des=ibed and as illustrated in the acc=panying drawings.

Published 1991 at 7be Patent Office. State House. 66/71 High Holborn. London WCIR47?. Further copies may be obtained from Sales Branch. Unit
6. Nine Mile Point Cwnifelinfach. Cross Keys. NewporL NPI 7HZ. Printed by Multiplex techniques lid. St Mary Cray, Kent.