GB2389868A

GB2389868A - Support backing for driving sheet piles

Info

Publication number: GB2389868A
Application number: GB0214210A
Authority: GB
Inventors: Roger Alfred Bullivant
Original assignee: Roxbury Ltd
Current assignee: Roxbury Ltd
Priority date: 2002-06-20
Filing date: 2002-06-20
Publication date: 2003-12-24
Also published as: GB0214210D0

Abstract

A driving arrangement (10) for driving a sheet-like member, such as a plastic pile (12) includes a backing plate (16) which carries a platen (20) at its upper edge, to serve as an anvil on which driving forces may be applied. A clamping arrangement (28), in the form of a spring, connects the backing plate (16) and the pile (12). During driving, the clamp arrangement (28) serves as an overbreaker. After driving, backing member (14) is withdrawn from the ground, being pulled clear from the grip of the clamping arrangement (28), which is left in the ground, beneath the pile (12).

Description

( 1 Driving The present invention relates to driving and in particular,

but not exclusively, to driving piles into the ground.

Some ground conditions require the formation of a continuous or substantially continuous barrier within the ground, for example to restrict movement of ground water, or to secure ground against erosion or the like.

The present invention provides a driving arrangement for drivmg a generally sheet-like member into the ground, and including a backing member which is stiff relative to the sheet-like member, and a damp arrangement operable to secure the sheet-like member to the backing member at or near the lower extremity of the sheet-like member, whereby the sheet-like member may be driven into the ground by driving forces applied to the backing member, and wherein the arrangement further includes an oversize member to serve as an overbreaker during driving, and the damp arrangement is operable to release as the backing member is withdrawn to leave the sheet-like member in the ground.

The bacldng member preferably has an anvil region to which the driving forces may be applied.

The clamp arrangement may include a spring clipping arrangement. The spring clipping arrangement may resiliently embrace the sheet-like member and the backing member. The arrangement may embrace from below, to release when the backing member is withdrawn. The spring clipping arrangement may be oversized to serve as the said overbreaker.

Examples of the present invention will now be described in more detail, by way of example only, and with reference to the accompanying drawings, in which Fig. 1 is a side elevation of a driving arrangement in accordance with the present invention, with a sheet-like member attached;

( Fig. 2 is a plan view of the arrangement of Fig 1; Fig. 3 is a plan view of two neighbouring sheet-like members after installation; and Fig. 4 is an enlarged plan view of the attachment between the sheet-like members of Fig. 3.

Figs. 1 and 2 show a driving arrangement 10 for driving a generally sheetlike member 12 into the ground. The member 12 will hereafter be called a pile.

The arrangement 10 includes a backing member indicated generally at 14. This has a backing plate 16 with a generally flat front face 18 and carrying a horizontal platen 20 at its upper edge, to serve as an anvil on which driving forces may be applied in the direction of the arrow 22. These forces may be by impact, vibration or the like. Reinforcing webs 24 extend down from the platen 20, being attached to the platen 20 and to the back plate 16 to strengthen the member 14 against buckling or other distortion during driving.

A clamping arrangement 28 is provided for clamping the pile 12 to the front face 18. The arrangement 28 is a spring member which extends across substantially the whole width of the back plate 16 and embraces the back plate 16 and pile 12 from below. That is, a lip 36 extends up the rear face of the back plate 16. A second lip extends up the front face 18. The lips meet at a resilient elbow 40 to grip the back plate 16 and pile 12 in the mouth between the lips 36, 38. The pile 12 is predominantly flat, as has been described, and may be made of a plastic material, such as by extrusion. The pile 12 has substantially vertical edges which are formed in generally complementary fashion, one edge having a vertical enlarged head 42, and the other having a vertical channel section 44. Consequently, a pile 12 can be driven alongside a pile which has already been installed in the ground, with the head 42 travelling down the

section 44 of the neighbouring pile, from above, thereby attaching the new pile to the existing pile as the new pile is driven to its final depth (see particularly Figs. 3 and 4).

It will be apparent that the edges of the pile 12, and particularly the channel section 44, are vulnerable while the pile 12 is being driven. The clamping arrangement 28 provides some protection to the channel section 44, as can now be described.

Fig. 2 illustrates a pile 12 bemg driven alongside a previously driven pile 12A. The head 42 of the pile 12 is interconnected with the channel section 44 of the previous pile 12A. The clamping arrangement 28 does not project beyond the back plate 16, in the direction of the previous pile 12A. However, at the other edge of the back plate 16, the lower clamp arrangement 28 does extend beyond the back plate 16, therebeing a short projection 48 which lies beneath the channel section 44.

It is also apparent from Fig. 2 that the thickness of the arrangement 28 (i.e. in a direction perpendicular to the plane of the back plate 16) is sigruficantly greater than the thickness of the pile 12 and also greater than the dimension of the section 44 in this direction. This arises from the form of the arrangement 28, as visible from Fig. 1. Consequently, the arrangement 28 serves as an overbreaker when the arrangement is being driven. That is to say, the arrangement 28 leads the driving and is wider than the apparatus to follow, so that some clearance is provided between the ground and the backing member 14 or pile 12. Furthermore, the arrangement 28 provides an overbreaker function below the channel section 44, reducing the liability of the section 44 to damage, by removing or mimmismg contact between the section 44 and the ground through which the pile 12 is being driven.

Once the arrangement 10, carrying the pile 12 and arrangement 28 has been driven to the required depth, upward forces, in the opposite direction to the arrow 22, are applied to the backing member 14 to withdraw it from the ground. As it does so, the backing member 14 is pulled clear from the grip of

the damping arrangement 28, which is retained in the ground by the presence of the pile 12. This releases the pile 12 from the backing member 14. The overbreaker 28 is therefore Lost" or 'sacrificial". The backing member 14 can be removed fully from the ground, leaving the pile 12 in situ and attached to the previous pile 12A.

Another pile 12 is then attached to the backing member 14, in the manner described, and can then be driven into the ground.

Attaching a pile 12 to the backing member 14 may be facilitated by arranging a joint between the anvil 20 and the mechanism of applying the driving force to the anvil, so that the backing member 14 can be swung up to place the back plate 16 in a horizontal position, allowing a new pile 12 to be readily laid onto the plate 16 before clamping.

Figs. 3 and 4 show views from above of two piles 12 installed, as described above, and each above a lost overbreaker 28.

A pile 12 of plastics material is likely to be relatively flexible, particularly when subjected to forces sufficiently large to provide driving. In particular, it is expected that a sheet pile of plastics material could not be top driven i.e. driven by forces applied to the uppermost extremity of the pile 12. This would cause buckling of the pile 12, particularly in the early stages of driving, likely to result in failure of the pile 12. However, the arrangement 10 allows top driving via the anvil 20. Consequently, the arrangement 10 allows the use of relatively flexible piles 12.

Furthermore, the arrangement allows a top driving action to be used with flexible piles drawn from stock on a roll, because the stock is pulled down by the clamp 28. That is, the backing member 16 receives top driving forces on the anvil 20, but applies bottom driving forces to the pile sheet, through the clamp 28. The skilled reader will appreciate that many variations and modifications

( 5 can be made to the apparatus described above, without departing from the scope of the present invention. In particular, dimensions, relative dimensions, shapes, sizes and materials could be varied according to the purpose of the pile being driven. Additional clips could be used, part way down the edges of the plate 16, if required, these being designed to release the plate 16 when being withdrawn. Other arrangements for retaining the pile 12 against the back plate 16 could be envisaged, such as suction or vacuum adhesion.

The pile may be treated to enhance friction with the surrounding ground.

For example, the surface may be treated by roughening, corrugation or application of granular material. Alternatively, the pile may be perforated.

Whilst endeavouring in the foregoing specification to draw attention to

those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.

Claims

I. 6 CLAIMS

1. A driving arrangement for driving a generally sheet-like member into the ground, and including a backing member which is stiff relative to the sheet-like member, and a clamp arrangement operable to secure the sheet-

like member to the backing member at or near the lower extremity of the sheet-like member, whereby the sheet-like member may be driven into the ground by driving forces applied to the backing member, and wherein the arrangement further includes an oversize member to serve as an overbreaker during driving, and the clamp arrangement is operable to release as the backing member is withdrawn to leave the sheet-like member in the ground.

:..

2. An arrangement according to claim 1, wherein the backing member has an anvil region to which the driving forces may be applied.

3. An arrangement according to claim 1 or 2, wherein the clamp arrangement includes a spring clipping arrangement.

4. An arrangement according to claim 3, wherein the spring clipping arrangement is operable, in use, to resiliently embrace the sheet-like member and the backing member.

5. An arrangement according to claim 4, wherein the arrangement is operable to embrace the sheet-like member from below, to release when the backing member is withdrawn.

6. An arrangement according to claim 4 or 5, wherein the spring clipping arrangement is oversized to serve as the said overbreaker.

7. A driving arrangement substantially as described above, with reference to the accompanying drawings.

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8. Any novel subject matter or combination including novel subject matter | disclosed herein, whether or not within the mope of or relating to the same I invention as any of the preceding claims.