GB2378968A

GB2378968A - Support structure

Info

Publication number: GB2378968A
Application number: GB0216977A
Authority: GB
Inventors: Leslie Nicholson
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-07-20
Filing date: 2002-07-22
Publication date: 2003-02-26
Also published as: GB0117667D0; US20030031514A1; GB0216977D0

Abstract

A reusable support assembly (1) for use with an excavated hole includes a number of piles (2), a perimeter frame (3) and bracing clamps (4) providing an adjustable support. The bracing clamps (4) include two engaging members (18, fig 10), at least one clamp stiffening device (22, fig 10) and an adjustable clamp extension mechanism (21, fig 10). The engaging members (18, fig 10) are cable of pivotal movement and are located at opposite ends of an axis as defined by the clamp stiffening device (22, fig 10) and the adjustable clamp extension mechanism (21, fig 10).

Description

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r, 1 Support Structure 3 The present invention relates to the field of support

structures. In particular it discloses an adaptable and 5 reusable support structure for the provision of structural support for excavated channels or holes.

In order to lay pipes, cables or telephone lines under 9 ground, it is necessary to excavate a hole or channel 10 along the route that such pipes or cables are required to ll be laid. These excavated channels or holes require 12 structural support in order that they do not collapse 13 while work is being carried out in laying the pipes or 14 cables. The level of support required for such excavated 15 sites depends directly on the dimensions of the channel 1C, or hole.

18 The prior art teaches of support structures for excavated

19 channels or holes that comprise piles, brackets and 20 waling beams. The procedure for deploying such support 2] structures requires the piles to be driven down into the 22 ground around the perimeter of the area to be excavated.

23 The piles are designed to interconnect with each other so

-.. . ] as to aid the structural support provided for the excavated channel or hole. This process then requires 3 the user to weld a plurality of brackets to the piles 4 around the entire perimeter of the excavated channel or a' hole. Thereafter, waling beams are cut and laid on top C of the said brackets again being secured by means of -1 welding. Welding is also employed in order to secure the intersection junctions of any two waling beams so as to I form a perimeter frame for the support structure.

1) ll The dimensions of the perimeter frame are then required 1 to be measured such that further support sections can be 13 cut from waling beams in order that they fit across the 14 breadth of an excavated channel or hole. These further 15 support sections are once again secured in place by means 16 of welding.

18 Deploying such structural supports can be both time 19 consuming and costly as they require both on site cutting 20 and welding in order to secure the waling beams and 21 brackets. Traditionally, brackets are only welded at a 22 pre-determined height in order that a single waling beam 23 can be laid across the top of the brackets. Therefore, 24 if an excavated channel or hole uncovers a subterranean 25 body that requires additional support to be deployed, 2 -: such as a gas mains, further welding and cutting of the 2<, brackets and waling beams is required.

29 When the work that was required to be carried out within 30 an excavated channel or hole is complete, the support 31 structure requires to be removed before the channel or 32 hole is re-filled. The employment of welding for the 33 various components complicates this removal process. It

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also results in the fact that piles, waling beams and brackets require to be cleaned before re-use.

3 Additionally, because of the cutting of the waling beams t and of the welding of the various sections these items 5 are often left damaged and unusable. Therefore, traditional support structures are inherently wasteful as 7 much of the support structure material is disposed of after use. This has the direct result of significantly cj increasing the costs involved in supplying such support 19 structures.

1'. 10 It is an object of the present invention to provide a 13 reusable support structure for use with an excavated 14 channel or hole that does not require welding in order to 15 be assembled.

17 It is a further object of the present invention to 18 provide a reusable support structure for use in an 19 excavated channel or hole that is inherently flexible so 2() being suitable for deployment with a variety of channels 21 or holes that incorporate subterranean bodies.

23 According to the present invention there is provided a 24 reusable support assembly for use with an excavated 25 channel or hole comprising a support structure having a 26 plurality of piles and a perimeter frame, and at least 27 one bracing clamp, wherein the bracing clamp provides an 28 adjustable support for the support structure.

30 Most preferably the bracing clamp is detachable from the 31 reusable support structure.

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À - ] Preferably the bracing clamp comprises encaging members for releasably connecting the bracing clamp to the support structure.

Preferably the piles comprise an attachment means wherein G the attachment means allows the perimeter frame to be located relative to the piles.

9 Preferably the attachment means comprises a plate, a lR support- bracket and a securing means for securing the 11 plate JO the pile.

it. 13 Preferably the plate comprises at least one locator.

1l Most preferably the locator is in the form of a wedge.

16 Preferably the support bracket comprises a support and a 1i wedge wherein the support bracket is attached to the 18 plate by locating the wedge within the locator.

1'3 2() Preferably the perimeter frame comprises a plurality of 21 beams and a plurality of connection means for connecting 22 two beams and securing said two beams in position.

24 Most preferably the beams comprise an H shaped cross 25 sectional profile.

27 Preferably the connection means comprises two brackets 28 and a connector pivoting means such that the brackets 29 pivot about the connector pivoting means.

31 Preferably the brackets comprise a bracket locator 32 adapted to locate the bracket on a beam and a plurality

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-. -. 1 of bracket securing means adapted to secure the bracket 2 to the beam.

l Preferably the bracket securing means comprises a threaded screw.

7 Preferably the bracing clamp comprises two engaging 8 members, at least one clamp stiffening crevice and at 9 least one adjustable clamp extension means, wherein the 1 engaging members are located at opposite ends of an axis ll as defined by the clamp stiffening device and the 12 adjustable clammy extension means.

1 Q ld Preferably the bracing clamp further comprises a hinge 15 plug and a fitting assembly associated with each of the 16 said engaging members, the hinge plug and fitting 17 assembly being adapted to attach the engaging member to 18 the end of the bracing clamp.

20 Preferably the engaging members comprises a main body, 2] two off axis clamp stiffeners, a hinged locator, a 2? pivoting port and a plurality of connecting ports.

24 Most preferably the off axis clamp stiffeners are 25 connected to the fitting assembly and the connecting 26 ports such that manual adjustment of the off axis clamp 27 stiffeners allows the engaging member to pivot about the 28 pivoting port.

30 Preferably the hinged locator comprises a hinge adapted 3] to allow the hinged locator to be positioned about a beam 32 of the perimeter frame, and a plurality of engaging

a,. e À- . 5. 1 member securing means adapted to secure the hanged locator to the beam.

) I Preferably the engaging member securing means comprises a ret threaded screw.

According to a second aspect of the present invention there is provided a bracing clamp for providing an 3 adjustable support to G support structure for use with an it exc.avated charnel or hole comprising: two encaging 11 members, at least one clamp stiffening device, and at 1.2 least one adjustable clamp extension means, wherein the 1-] engaging members are located at opposite ends of an axis 14 as defined by the clamp stiffening device and the 15 adjustable clamp extension means.

17 Preferably the bracing clamp further comprises a hinge 18 plug and a fitting assembly associated with each of the 19 said engaging members, the hinge plug and fitting 20 assembly being adapted to attach the engaging member to 21 the end of the bracing clamp.

23 Preferably the engaging members comprise a main body, two 24 off axis clamp stiffeners, a hinged locator, a pivoting 25 port and a plurality of connecting ports.

27 Most preferably the off axis clamp stiffeners are 28 connected to the fitting assembly and the connecting 29 ports such that manual adjustment of the off axis clamp 30 stiffeners allows the engaging member to pivot about the 31 pivoting port.

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.. 1 a 1 Preferably the hinged locator comprises a hinge adapted 2 to allow the hinged locator to be positioned about a beam of the perimeter frame, and a plurality of engaging 4 member securing means adapted to secure the hinged 5 locator to the beam.

7 Preferably the engaging member securing means comprises a g threaded screw.

f3 1() According to a third aspect of the present invention 11 there is provided support structure for use with an 1;' excavated channel or hole comprising a perimeter frame 13 having a plurality of beams and a plurality of connection 19 means for connecting two beams and securing said two 15 beams in position.

17 Most preferably the beams comprise an H shaped cross 13 sectional profile.

1Q 20 Preferably the connection means comprises two brackets 21 and a connector pivoting means such that the brackets 22 pivot about the connector pivoting means.

24 Preferably the brackets comprise the brackets comprise a 25 bracket locator adapted to locate the bracket on a beam 26 and a plurality of bracket securing means adapted to 27 secure the bracket to the beam.

29 Preferably the bracket securing means comprises a 30 threaded screw.

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l Embodiments of the present invention will now be described, by way of example only, with reference to the <. accompanying figures, in which: 5 Figure 1 illustrates a schematic presentation of a 6 reusable support structure in situ with an excavated 7 channel; Fi;ure illustrates a cross sectional profile of a 10 waling beam as used in the reusable support 11 structure; 1 i' 13 Figure 3 illustrates a top view of a corner bracket 14 of the reusable support structure; 1 A) 16 Figure 4 illustrates a cross sectional view of the 17 corner bracket of the reusable support structure; 19 Figure 5 presents a top view of an attachment means 20 for a perimeter frame and a pile of the reusable 2] support structure; 23 Figure 6 presents a front view of the attachment 24 means for the perimeter frame and the piles of the 25 reusable support structure; 27 Figure 7 presents a support bracket hanger of the 28 reusable support structure; 3() Figure 8 presents a front view of a piling support 31 bracket of the reusable support structure;

- À e.. À À: À À : l Figure 9 presents a front view and side view of a wedge of the piling support bracket; 4 Figure 10 presents a bracing clamp of the reusable support structure; and 7 Figure 11 presents an exploded illustration of the bracing clamp.

10 Figure 12 presents a side profile of a clamp of the ll bracing clamp.

1? . 13 Figure 13 presents a clamp stiffener of the bracing 19 clamp.

16 Flqure 14 presents a detail of a bracing clamp in 17 accordance with an alternative embodiment.

19 Referring initially to Figure 1, a reusable support 20 structure 1 can be seen to comprise of a plurality of 21 piles 2, a surface perimeter frame 3 and two bracing 22 clamps 4 24 The surface perimeter frame 3 can be seen to further 25 comprise four waling beams 5 and four corner brackets 6.

26 Figure 2 illustrates a cross sectional profile of the 27 waling beams 5. It can be seen that such waling beams 5 28 have an H shaped cross sectional profile and so are ideal 29 for the attachment of additional components of the 30 support structure 1, as described below.

3] 32 In particular Figure 3 presents a top view of one of the 33 corner brackets 6 attached to two waling beams 5. The

À. 1 corresponding cross sectional profile is presented in I' Figure 4. The corner bracket 6 can be seen to comprise 3 two bracket sections 7 that are attached via a pivoting 4 means 8 Each bracket section 7 further comprises a rat locator '3 and four threaded screws 10 that in combination 6 provide the securing mechanism for the bracket section 7 to a walling beam 5.

A locator 9 is positioned around a waling beam 5 and is it' thereafter secured in place by the threaded screws 10.

1] With both bracket sections 7 attached as described, the 12 corner bracket 6 provides a rigid securing means for the 13 perimeter frame 3. However, the corner brackets 6 permit 14 easy adjustment of the perimeter frame 3 by simply 1 ray loosening the threaded screws 10 and allowing the corner 16 bracket 6 to move about the pivoting means 8.

18 Figures 5 and 6 show how the perimeter frame 3 is 19 attached to the piles 2. In particular Figure 5 presents 20 a top view of a single pile 2 including a section of the 21 perimeter frame 3 and the attachment means 11, while 2.: Figure 6 presents the corresponding front view. The 23 attachment means 11 comprises at least one wedge shaped 24 locator l2 mounted on a hanger plate 13 and a piling 25 support bracket 14. A hanger plate 13 may incorporate a 26 number of wedge shaped locators 12 so as to provide 27 flexibility in the height at which the perimeter frame 3 28 is positioned.

2'3 30 The hanger plate 13 is secured to the piles 2 via a 31 support bracket hanger 15, a side view of which is 32 presented in Figure 7. The support bracket hanger 15 is 33 tightened in place by two threaded screws 10.

- À- À ^ Àe À l Figure 8 presents a front view of the piling support 2 bracket 14 that can be seen to comprise a support 16 and 3 a wedge 17. Figure 9 presents a front and side view of 4 the wedge 17 of the pile support bracket 14.

6 The bracing clamp 4, as employed by the reusable support 7 structure 1, is presented in Figure 10 and in an exploded 8 form in Eigure 11. It comprises two clamps 18, two hinge 9 plugs 19, two fitting assemblies 20, a clamp extension 10 pipe 21, an on-axis clamp stiffener 22, and four offaxis 11 clamp stiffeners 23.

13 A side profile of the clamp 18 is shown in Figure 12.

14 The clamp 18 can be seen to comprise a main body 24, a 15 hinged locator 25, a hinge 26, two location ports 27, a 16 central pivoting port 28, and threaded screws 29 for 17 securing the clamp 18. The hinge 26 within the hinged 18 locator 25 allows the clamp 18 to be readily position 19 about a waling beam 5. Thereafter, the clamp 18 can be 20 secured in place by tightening the threaded screws 29.

21 The clamp 18 is designed such that when it is 22 incorporated with the other components of the bracing 23 clamp 4 it can be manually pivoted about the central 24 pivoting port 28.

26 The clamp extension pipe 21 is step-wise extendible such 27 that the bracing clamp 4 can be employed with a range of 28 channels or holes. It is the dimensions of the channel 2 9 or hole that dictates the choice of length of the clamp 30 extension pipe 21. The clamp extension pipe 21 is also 31 interchangeable so as to allow for substitution if the 32 dimensions of the channel or hole are out with the range 33 of extension of a particular clamp extension pipe 21.

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r - À 1 dimensions of the channel or hole are out with the range 2! Of extension of a particular clamp extension pipe 21.

) iI Further detail of the on axis clamp stiffener 22 is 5 presented in Figure 13. The clamp stiffeners 22 compris 6 an extendible ratchet means 30 and two connection ports 7 31 that enable the extendible ratchet means 30 to be connected to the other components of the bracing clamp 4 It should be noted that the off axis clamp stiffener 23 10 acts iJ1 arl identical manner to the on axis stiffener 22 1] but simply on a smaller scale. Incorporation of the 12 extendible ratchet means 30 in the clamp stiffeners 22 13 and 23 allows the bracing clamp to be manually adjusted 14 and secured once in position.

1 r: 16 The hinge plugs 19 and the fitting assemblies 20 17 incorporate connection ports 32 that allow them to be 18 employed as adapter units within the bracing clamp 4.

19 This allows the bracing clamp 4 to be constructed from 20 the various modular components. The modular nature of 21 the bracing clamp 4 results in it being highly adaptable 22 and so suitable for use with a range of channels and 23 holes.

25 In order to deploy the support structure 1 a series of 26 interconnected piles 2 are driven into the ground around 27 the perimeter of the area to be excavated. Thereafter, 28 pile support brackets 14 are attached to the hanger 29 plates 13 via the wedge shaped locators 12.

31 At this stage by cutting waling beams 5 to the required 32 length the perimeter frame 3 can be constructed.

33 Employing the corner brackets 6 allows the cut lengths of

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i; t l waling beam 5 to be secured together so forming the 2 perimeter frame 3 as required. The perimeter frame 3 is then rested on top the pile support brackets 14.

5 As further excavation takes place the stress and strain 6 experienced by the piles 2 and the perimeter frame 3 7 increases, therefore requiring the provision of 8 additional support. This additional support is provided in the form of the bracing clamps 4.

In 11 The bracing clamps 4 have one end attached to one side of 1 the perimeter frame 3 via one of the clamps 18. The 13 length of the clamp extension pipe 21 is then chosen to 14 be of the required length for the dimensions of the 15 channel The on axis clamp stiffener 22 is then manually 16 adjusted such that the second clamp 18 is in a position 17 to be attached to the opposite side of the perimeter 18 frame 3. The incorporation of the off-axis clamp 19 stiffeners 23 allows the angle of the clamps to be varied 20 so as to take account of non-parallel sides of the 21 perimeter frame.

23 Figure 14 shows a bracing clamp in accordance with an 24 alternative embodiment of the invention. In this 25 embodiment, the bracing clamp 4 is provided with 26 additional jack gussets 33, 34 mounted either side of the 27 on-axis clamp stiffener 22. The jack gusset 33 is welded 28 to the fitting assembly 20, with the jack gusset 39 29 welded on the clamp pipe. The jack gussets extend in a 30 radial direction from the main axis of the clamp, and AL provide inner surfaces 35, 36 (or partial surfaces) in 3' planes perpendicular to the main axis.

À 1 The jack gussets 33, 34 function to aid in the removal of the bracing c-lamp When the clamps are in use, they are braced against the perimeter frame. A reaction force 4 from the surrounding earth acts on the clamp via the 5 perimeter frame. This force tends to resist the C loosening of the threaded collar 37 on the threaded shaft 7 38 which forms part of the on-axis clamp stiffener 22.

Depending on the magnitude of the compression provided by " the clamps, the threaded collar may prove to be difficult 1(! to loosen, hampering the removal of the device.

1. This embodiment allows a jack 39, such as a hydraulic 18 jack, to be placed between the jack gussets 33, 34 during 14 the removal of the clamp. The jack abuts the inner 1 r) surfaces and forces the jack gussets away from one 16 another, thereby providing a temporary, supplementary, 17 support to the clamp. This support relieves the 13 resistance to the loosening of the threaded collar, which 19 can be undone without the same degree of effort. The 20 jack can then be released, and the clamp removed.

22 Figure 14 shows the clamp in plan view, with the jacking 23 gussets provided at one side of the main axis of the 21 clamp, for the purposes of clarity. However, it is 25 important to note that the jack gussets could be mounted 26 in any position about the main axis of the clamp, for 27 example, so that they protrude radially from the main 28 axis in an upward direction.

30 Once deployed, as outlined above, the bracing clamp 4 31 provides the additional structural support required. It 32 is known to those skilled in the art that the spacing of 33 the bracing clamps 4 depends on its own dimensions and

À. 1 the depth of the excavation. On passing certain depths 2 it may be required to incorporate a second layer of support om: rising a second perimeter frame 3 and a 4 second series of bracing clamps 4.

6 Other unforeseen factors can lead to the requirement of 7 further localized support. For example subterranean P bodies such as gas mains, water pipes or telephone cables I can be uncovered. The presence of such bodies requires 10 the provision of additional support so as to avoid damage ll to the subterranean body.

1z 13 The present invention is ideal for employment with 14 excavations of considerable depths and with the scenario 15 of unexpected subterranean bodies. Added to the fact I6 that an excavation is rarely regular in its geometry a 17 degree of flexibility is highly desirable.

19 The presence of additional wedge shaped locators 12 on 20 the hanger plates 13 allows for a second layer of support 21 to be easily incorporated in a similar fashion to the 22 first. The present invention also allows additional 23 bracing clamps 4 to be easily added around subterranean 24 bodies. The additional problem of irregular excavations 25 can also be easily dealt with by adjusting the corner 26 brackets 6 on the perimeter frame 3 and the clamp 27 stiffeners 22 and 23 of the bracing clamps 4.

29 The flexibility of the reusable support structure 1 can 30 be exploited still further. Although the above 31 embodiment refers to predominately rectangular 32 excavations the present invention is not restricted to 33 such geometrical shapes. The corner brackets 6 and clamp

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a l stiffeners 22 and 23 permit the support structure 1 to 2 employ other regular and irregular shaped perimeter 3 frames 3 r:: The support structure 1 of the present invention is also 6 inherently reusable. As no welding is required in deploying the piles 2, perimeter frames 3 or bracing À' clamps 4 there is no requirement for cleaning leading to 9 a significantly reduced chance of damage to these 1() components. Therefore the component parts can be easily ll re-dep]oyed so cutting down the wastage inherent with 1' systems as taught n the prior art.

14 An advantage of the present system is that it provides a 15 reusable support structure for use with an excavated IF, channel or hole that is formed from modular components 1? and does not require welding in order to be assembled.

19 A further advantage of the present invention is that it 2() provides a reusable support structure for use in an 21 excavated channel or hole that is inherently flexible so 22 being suitable for deployment with channels or holes of 23 both regular or irregular shape.

25 A yet further advantage of the present invention is that 26 it provides a reusable support structure for use in an 27 excavated channel or hole that that can easily be adapted 28 to strengthen areas around subterranean bodies.

30 A yet further advantage of the present invention is that 31 it provides a reusable support structure for use in an 32 excavated channel or hole that significantly reduces 33 wastage of the component parts.

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. Further modifications and Improvements may be added without departing from the scope of the 1c.vention herei n 3 i mended.

Claims

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1 CLAIMS:

I, 3 1. A reusable support assembly for use with an excavated channel or hole comprising: r) - a support structure having a plurality of piles and a perimeter frame, and; - at least one bracing clamp, wherein the bracing clamp provides an adjustable support for the t support structure.

11 2. A reusable support assembly as claimed in Claim 1

1, wherein the bracing clamp is detachable from the 13 support structure.

15 3 A reusable support assembly as claimed in Claim l 16 or Claim 2 wherein the bracing clamp comprises 17 engaging members for releasably connecting the 1 bracing clamp to the support structure.

20 4. A reusable support assembly as claimed in any 2] preceding Claim wherein the piles comprise an 2 attachment assembly that allows the perimeter frame 23 to be located relative to the piles.

25 5. A reusable support assembly as claimed in Claim 4 26 wherein the attachment assembly comprises a plate, 27 a support bracket and a securing means for securing 28 the plate to the pile.

30 6. A reusable support assembly as claimed in Claim 5 31 wherein the plate comprises at least one locator.

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] 7. reusable support assembly as claimed in Claim 6 2 wherein the locator is in the form of a wedge.

8. A reusable support assembly as claimed in Claim 6 5 wherein the support bracket comprises a support and 6 a wedge, and the support bracket is attached to the 7 plate by locating the wedge withi- the locator.

tJ 9. A reusable support assembly as claimed in any lO preceding Claim wherein the perimeter frame 11 comprises a plurality of beams and a plurality of 12 connection means for connecting two beams and 13 securing said two beams in position.

15 10. A reusable support assembly as claimed in Claim 9 16 wherein the beams have an H-shaped cross sectional 17 profile.

19 11. A reusable support assembly as claimed in Claim 9 2n or Claim 10 wherein the connection means comprise 21 two brackets and a connector pivoting means such 22 that the brackets pivot about the connector 23 pivoting means.

25 12. A reusable support assembly as claimed in Claim 11 2h wherein the brackets comprise a bracket locator 27 adapted to locate the bracket on a beam and a 28 plurality of bracket securing means adapted to 29 secure the bracket to the beam.

3] 13. A reusable support assembly as claimed in Claim 12 32 wherein the bracket securing means comprise a 33 threaded screw.

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. . t . 1 14. A reusable support assembly as claimed in any pre edging Claim wherein the bracing clamp comprises 3 two engaging members, at least one clamp stiffening device and at least one adjustable clamp extension r) means, wherein the engaging members are located at 6 opposite ends of an axis as defined by the clamp 7 stiffening crevice and the adjustable clamp - extensjcjn means.

10 15. reusable support assembly as claimed in Claim 14 11 wherein the bracing clamp further comprises a hinge 12 plug and a fitting assembly associated with each of 13 the said engaging members, the hinge plug and 11 fitting assembly being adapted to attach the 15 engaging member to the end of the bracing clamp.

17 16. A reusable support assembly as claimed in Claim 14 18 or Claim 15 wherein the engaging members comprise a 19 main body, two off-axis clamp stiffeners, a hinged 20 locator, a pivoting port and a plurality of 21 connecting ports.

23 17. A reusable support assembly as claimed in Claim 16 24 wherein the off-axis clamp stiffeners are connected 25 to the fitting assembly and the connecting ports 26 such that manual adjustment of the off axis clamp 2-1 stiffeners allows the engaging member to pivot 28 about the pivoting port.

30 18. A reusable support assembly as claimed in Claim 16 31 or Claim 17 wherein the hinged locator comprises:

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. r l - a hinge adapted to allow the hinged locator to be positioned about a beam of the perimeter frame, 2, and; 9 - a plurality of engaging member securing means 5 adapted to secure the hinged locator to the beam.

7 19. A reusable support assemb y as claimed in Claim 18 - wherein the engaging member securing means 3 comprises a threaded screw.

1() 11 20. A bracing clamp for providing an adjustable support 12 to a support structure for use with an excavated 1.] channel or hole comprising: two engaging members, 14 at least one clamp stiffening device, and at least 15 one adjustable clamp extension means, wherein the 16 engaging members are located at opposite ends of an 17 axis as defined by the clamp stiffening device and 18 the adjustable clamp extension means 20 21. A bracing clamp as claimed in Claim 20 further 21 comprising a hinge plug and a fitting assembly 22 associated with each of the said engaging members, 23 the hinge plug and fitting assembly being adapted 24 to attach the engaging member to the end of the 25 bracing clamp.

27 22. A bracing clamp as claimed in Claim 20 or Claim 21 28 wherein the engaging members comprise a main body, 29 two off-axis clamp stiffeners, a hinged locator, a 30 pivoting port and a plurality of connecting ports.

32 23. A bracing clamp as claimed in Claim 22 wherein the 33 off axis clamp stiffeners are connected to the

r À . I fitting assembly and the connecting ports such that 2 manual adjustment of the off-axis clamp stiffeners allows the engaging member to pivot abc,ut the 4 pivoting port.

6 29. A bracing clamp as claimed in Claim 22 or Claim 23 wherein the hinged locator comprises: x - a hinge adapted to allow the hinged Jocator to be positioned about a beam of the perimeter frame, I () and; 12 - a plurality of engaging member fasteners adapted 1' to secure the hinged locator to the beam.

14 25. A bracing clamp as claimed in Claim 24 wherein the 15 engaging member securing means comprises a threaded 16 screw.

1P 26. A support structure for use with an excavated 19 channel or hole comprising: 20 - a perimeter frame having a plurality of beams and 21 a plurality of connection means for connecting two 22 beams and securing said two beams in position.

2< 24 27. A support structure as claimed in Claim 26 wherein 2r, the beams have an H-shaped cross sectional profile.

27 28. A support structure as claimed in Claim 26 or Claim 28 27 wherein the connection means comprise two 29 brackets and a connector pivoting means such that 3() the brackets pivot about the connector pivoting 31 means.

! 29. A support structure as claimed in Claim 28 wherein the brackets comprise a bracket locator adapted to 3 locate the bracket on a beam and a plurality of 4 bracket securing means adapted to secure the 5 bracket to the beam.

7 30. A support structure as claimed in Claim 29 wherein L the bracket securing means include threaded screws.

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