AU643873B2 - Improvements in and/or relating to crib walls and components therefor - Google Patents

Description

1 6'43S73

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

C

9. 999.

Wa.ne of Applicant(s): 2Ac--tual Inventor(e) A-aaress for Service: -rivention Title: ROGER JAMES SCEATS ROGER JAMES SCEATS CULLEN CO., Patent Trade Mark Attorneys, 240 Queen Street, Brisbane, Qid. 4000, Australia.

IMPROVEMENTS IN AND/OR RELATING TO CRIB WALLS AND COMPONENTS THE RE FOR 9* 9.

9999 9* 9.

9 *9.9 9. 9 99 !lte following statement is a full description of this invention, i icluding the best method of performing it known tt- us: The present invention relates to improvements in and/or relating to crib walls and in particular, although not exclusively, to a timber closed cell crib wall construction.

To the present time various methods of constructing crib walls and components therefor have been available. Crib walls formed of concrete are expensive and the components are heavy to handle.

The most commonly used form of timber crib wall is a structure consisting of alternating layers of headers and stretchers. Headers run perpendicular to a bank to be supported and may be provided with notches to locate with stretchers which run parallel to a bank.

In prior constructions gaps have been provided between adjacent headers. Where the crib wall is reasonably hi~h, and the headers are of reasonable e0 length, large forces are exerted upon the lower headers. To overcome this problem header support blocks may be provided between lower headers. New Zealand patent no. 205792 discusses this form of crib wall construction and discloses a method in which the header support blocks are provided with tongues which locate within grooves of the headers.

This form of construction has the disadvantage that fill material can escape from the ends of cells and that header support blocks must be provided for structural support.

-3- It is an object of the present invention to provide a crib wall constructirn and components therefor which overcome the above disadvantages or at least provide the public with a useful choice.

Further objects of the invention will become apparent from the following description.

According to a first aspect of the invention there is provided a crib wall comprising: a plurality of substantially parallel columns of headers, with each header of a higher tier being supported substantially along its length by a header below; and ii) a plurality of tiers of stretchers interposed between at least some of the tiers of headers, 15 said stretchers running between the columns of headers near the front and rear edges thereof, said stretchers being of substantially triangular cross-section.

The invention also provides headers, stretchers and 20 header locks '3r building the crib wall of the invention.

S"The invention will now be described by way of reference to a possible embodiment thereof in which KLfLs reference is made to -4the accompanying drawings in which: Figure 1: Figure 2: Figure 3: Figure 4: Shows a side top perspective view of a header Shows a bottom perspective view of a stretcher Shows a header lock Shows a perspective view of a crib wall constructed from the huaders, stretchers and header blocks shown in Figures 1 to 3.

Shows a detailed end view of a portion of the wall shown in Figure 4.

Shows a frontal view of the crib wall shown in Figure 4.

Shows an end view of the crib wall shown in figure 4 in use retaining a bank.

S.

C

Figure 5: Figure 6: Figure 7: The crib wall of the present invention may be used in retaining wall or free standing applications. The components of the wall will preferably be formed of timber.

The present invention discloses a crib wall and components therefor in which columns of headers form substantially sealed walls to form a number of closed cells between columns of headers. This construction has the advantage that the filling material does not escape from the end of each cell.

It has the further advantage that upper headers are supported by the headers below substantially along their length, which avoids the need for header support blocks and thus removes a step in constructicn.

The present invention preferably also utilises triangular stretchers wherein the hypotenuse of the triangle faces inwardly. This gives superior fill retention characteristics whilst also economising on the amount of material required for stretchers.

S..Before describing the crib wall assembly, each crib wall component will be described. A top perspective view of a header 1 is shown in Figure 1. The header is provided with rectangular transverse rebates 2 along the top edge of the header at either end thereof. Transverse triangular rebates 3 are provided along the bottom edge of either end thereof.

V

Referring now to Figure 2 a bottom perspective view of a stretcher 4 is shown. Base 5 and vertical side 6 form the right angled sides of a triangle.

Transverse rebates 7 are provided at intervals along sides 5 and 6. In Figure 2 only one transverse rebate 7 is shc, i, although it is to be appreciated that several may be provided along the length of a stretcher. In use rebate 7 in side engages with rebate 2 in header 1. The hypotenuse 3ide 8 of stretcher 4 is oriented inwardly so that fill material is retained.

Stretcher 4 is also provided with end rebates 9 at either end. Again, these rebates are in sides 5 and 6 only. The end rebates 9 are however of only half the length of rebates 7. Rebates 7 are of slightly greater length than the width of header 1 so that the header will easily engage within rebates 7. Rebates 9 are of half the length of rebates 7. This is so that rebates 9 of adjacent stretchers can meet at a header and each be equally supported by the header.

Edge 10 of stretcher 4 is truncated parallel to side 6. If a perfectly triangular cross-section were used the edge 10 would be easily crushed and allow movement in the structure. Accordingly, edge il is truncated to provide an edge of reasonable thickness to spread the load.

Referring now to Figure 3 a header lock is shown in perspective. The header lock is of substantially the same cross-section as stretcher 4. Rebates 12 are provided in header lock 11 corresponding substantially to rebates 7 in stretcher 4. Again, these rebates are provided in the right-angled sides and not in the hypotenuse side.

.Referring now to Figures 4, 5, 6 and 7, crib ralls assembled from the components shown in Figures 1 to 3 are shown.

To assemble the crib wall structure two rows of stretchers 4 are laid parallel to a bank to be supported spaced apart the distance between rebates 3 of header 1. The bases 5 of the stretchers face downwards. The hypotenuse faces 8 of the two rows of stretchers face inwards. This assists in retaining fill within the crib wall. Headers are then placed normal to the stretchers engaging with rebates 7 of face 6.

The triangular transverse rebates 3 of headers 1 engage with the triangular portion formed by the sides 6 and 8 of stretchers 4. The vertical face of 3a of transverse triangular rebate 3 slides within recess 7 in face 6. Further tiers are then assembled in similar fashion.

As edges 13 and 14 of rebates 7 overhang the sides of S- headers 1, lateral movement of adjacent headers is restricted. The stretchers also ensure that adjacent stacks of headers are maintained a fixed distance apart the distance.between reLates 7).

In this way it is ensured that adjacent headers remain positioned one on top of another and columns of headers remain a fixed distance apart from one another adjacent columns of headers are parallel). This prevents relative movement of columns of headers under the force of fill.

The stretcher's engagement with transverse rebates 2 and 3 also prevents relative longitudinal movement between adjacent headers. This prevents headers moving longitudinally with respect to one another.

Referring now to Figure 5 a perspective view of a section of crib wall is shown. The right-hand side is the rear of the crib wall adjacent a bank to be supported. The left-hand side is the front of the crib wall. Stretchers are provided between adjacent headers along the front wall. Stretchers are required between each adjacent header along the front wall to retain fill.

Along the rear however, stretchers are not necessary to retain fill where a bank is to be supported. In these cases all that is required is a sufficient number of stretchers to maintain the relative positions of the columns of headers. Header locks 11 may be provided between some of the headers instead of complete stretchers. The header locks 11 20 ensure that adjacent headers do not move laterally with respect to one another. In a preferred embodiment stretchers are only provided at the rear of the crib wall between alternate tiers of stretchers. Header locks are provided elsewhere.

Where stretchers meet over a header the stretcher of the next tier should engage with the next header in the middle thereof. This ensures the structure remains locked together.

This form of construction has the advantage that the first layer of headers and stretchers form a suitable base for construction directly on top of earth. No foundation is normally necessary.

Example Headers 1 may be formed of 200mm x 50mm timber.

Rebates 2 may be about 10mm deep. Base 5 may be wide with side 6 being 85mm wide. Header lock 12 may 10 be of similar cross-section. Rebates 7 may be provided at intervals of between 600mm and 1,500mm.

When completed the crib wall structure may be filled with fill material. Where the crib wall is to be used in bank retention the crib wall may be angled towards the bank as shown in Figure 7. Where the crib wall is to be freestading stretchers should be provided at the front and rear between each tier of headers no headers locks used).

It is thus seen that the present invention provides a simple and effective crib wall and components therefore.

*Where in the foregoing reference has been made to specific components or integers having known equivalents then such equivalents are herein incorporated as if individually set forth.

Although this invention has been described by way of example and with reference to a possible embodiment thereof it is to be appreciated that improvements or modifications may be made thereto without departing from the scope of the invention as defined in the appended claims.

Claims (11)

1. A crib wall comprising: i) a plurality of substantially parallel columns of headers, with each header of a higher tier being supported substantially along its length by a header below; and ii) a plurality of tiers of stretchers interposed between at least some of the tiers of headers, said stretchers running between the columns of headers near the front and rear edges thereof, said stretchers being of substantially triangular cross-section.

2. A crib wall as claimed in claim 1 wherein the 0 15 cross-section of the stretchers is substantially a right angled triangle and the hypotenuse face of each stretcher faces inwardly. *9*at*

3. A crib wall as claimed in claim 2 wherein lateral rebates are provided at intervals along 20 the stretchers. S4. A crib wall as claimed in claim 3 wherein rebates are provided at either end of the a stretcher and are half the length of at least one rebate provided between the ends. -12- A crib wall as claimed in claim 1 wherein substantially rectangular transverse rebates are provided at each end of the top edge and substantially triangular rebates are provided at each end of the lower edge of each header.

6. A crib wall as claimed in claim 1 wherein stretchers are provided between each tier of headers along the front wall of the crib wall and stretchers are provided between each alternate tier of headers along the back wall of the crib wall, with header locks being provided between adjacent headers without stretchers therebetween.

7. A crib wall as claimed in claim 6 wherein the cross-section of the header lock is substantiallir a 15 right angled triangle and rebates are provided in the faces forming a right angle.

8. A header suitable for use in the crib wall of claim 1, of substantially rectangular cross-section provided with substantially rectangular transverse rebates at each end of the top edge and substantially triangular transverse rebates at each end of the lower edge. -13-

9. A stretcher suitable for use in the crib wall of claim 1, having a cross-section of substantially a right angled triangle wherein transverse rebates are formed in the sides forming a right angle and end rebates are provided at either end of the stretcher which are half the length of the transverse rebates. A header lock suitable for use in the crib wall of claim 1, provided with transverse rebates in the middle portion thereof and having a cross section of substantially a right angled triangle.

11. A timber crib wall substantially as herein described with reference to figures 4 to 7 of the accompanying drawings.

12. A header substantially as herein described with 15 reference to figure 1 of the accompanying drawings.

13. A stretcher substantially as herein described with reference to figure 2 of the accompanying -drawings. .1*

14. A header lock substantially as herein described 20 with reference to figure 3 of the accompanying drawings. drawings. C -14- A kit comprising a header as claimed in claim 8, a stretcher as claimed in claim 9, and a header lock as claimed in claim DATED this 22nd day of September 1993 ROGER JAMES SCEATS By his Patent Attorneys CULLER CO A S A A. *U A S A S S S A S S S .5.5 S. S S S S. S S.