GB2165879A - Retaining walls - Google Patents

Abstract

A wall for retaining grain or other granular material is constructed from a number of adjacent sheets (12) of high tensile material (e.g. steel or plastics), which are constrained by the weight of the granular material (22) to take a curved shape, in which shape the sheets are held in tension. <IMAGE>

Description

SPECIFICATION Improvements in or relating to retaining walls The present invention relates to retaining walls and more particularly to retaining walls for the storage of grain or other similar granular material.

A known retaining wall is formed from a number of "L" shaped sections made for example from reinforced concrete or heavy gauge (e.g. 6mm) steel sheet or corrugated thin sheet. The sections are placed in position alongside one another to form a wall of desired length. A disadvantage of this type of wall structure is that as the desired height of the wall increases the weight of the wall members increases. For walls of 4 metres high the weight of each section of retaining wall, will be such that mechanical handling means e.g. a tractor, is necessary to position the wall members.

Also as the required height increases the "L" shaped sections have to be made within an increased length of the "foot" portion of the "L" because this is required to counter the outward force against the wall by the weight of granular material producing a downward force on the foot portion which is inside the retained enclosure. This creates problems when it is necessary to store the retaining wall sections as they are heavy and are large and awkwardly shaped.

It is an object of the present invention to provide a retaining wall which is substantially lighter in construction and more easily stored than the above mentioned structures but which is still modular in design to enable variable length walls to be constructed.

According to the present invention there is provided a retaining wall for retaining grain or other granular material the wall comprising one or more sheets of high tensile material which in use takes a curved shape which is determined by the weight of the retained material.

A high tensile material is defined for the purposes of the present invention as being a material such as sheet steel, strong fabric or similar which can withstand the tensile forces imposed upon it by the weight of the granular material to be retained.

The granular material will normally be grain stored for example in a barn or like structure but the inventive retaining wall may be used to retain sand, gravel or soil or other similar granular materials.

In a preferred embodiment the sheet material is steel and in a preferred embodiment the sheets are substantially rectangular.

Each sheet forming a portion of the retaining wall is preferably supported at its upper end by a stanchion which may be provided with cross bars to co-operate with a turned over upper edge of each sheet. The stanchion or stanchions may be supported prior to filling by one or more wire ties affixed to an appropriate part of a barn like structure within which the granular material is to be stored or by a "tripod" type leg structure.

Preferably the sheets are joined in a manner such that the joint is not substantially stronger than each individual sheet such that substantially no bulging effect is created. In a preferred form the sheets are overlapped in an intermeshing finger arrangement.

Embodiments of the present invention will now be described, by way of example with reference to the accompanying drawings, in which: Figure 1 shows a cross-section side elevation view of a retaining wall according to the present invention; Figure 2 shows a front elevation view of a portion of the retaining wall of Figure 1; Figure 3 shows in cross-sectional side elevation a second embodiment of a retaining wall according to the present invention; and Figure 4 shows a possible jointing system for the sheets of the retaining wall.

With reference now to Figures 1 and 2, the retaining wall 10 includes a number of sheets of high tensile material 12, 14, 16, 18 and 20, sheets 12 and 20 being shown with broken edges to indicate the possible continuance of the wall on either side.

Each wall section is supported, during the period before the granular material 22 is present, by a stanchion 24, 26, 28 each stanchion having support legs 30, 32; 34, 36; 38, 40 which may be provided with support pads 42 (Figure 1) each stanchion also being preferably provided with support pads 44. The support pads 42, 44 may be fixed e.g.

bolted to the floor 46 of the barn or like structure (not shown) within which the granular material 22 is to be stored.

The sheet material 12 etc. is, in the embodiments of Figures 1 and 2, hung onto the stanchions 24 etc by turning over the upper edge of each sheet as shown at 48 (Figure 1). Each stanchion 24, 26, 28 may be provided with cross bars 50, 52; 54, 56' and 58, 60 to further support the sheets 12, 14, 16, 18, 20.

The stanchion between sheets 18 and 20 is omitted in Figure 2 to show the join 62 of the sheets.

The sheets used may be of any suitable high tensile material which will withstand the forces imposed on it by the weight of the granular material 22. The "fill" line of the granular material is shown by the dotted line 64 in Figure 1, and the weight of the granular material 22 causes the sheet material to take a form in which the sheets are subjected to tensile forces and which by withstanding such forces the granular material is retained. The form shown in Figures 1 and 3 (to be referred to hereinafter) is exemplary only for a particular height H of structure and for a particular grain size and weight of retained material. For different heights, grain size and weight the form taken by the sheets will vary.

Each sheet 12, 14, 16, 18, 20 is "buried" under the retained material to a length Y-Z which is also determined by the height H of the retaining wall and by the type of the granular material to be retained.

Thus the profile of the sheet 12 will be determined by the characteristics of the retained material, the material of the sheet, the length X Y of the retaining wall and the positions X and Y.

An alternative embodiment is shown in Figure 3 in which the sheets 12, 14, 16, 18, 20 are initially held in position, prior to filling the enclosure with the granular material 22, by a number of wires 66 (of which only one is shown) which are attached to the top of the stanchions 24, 26, 28. Each wire 66 is attached to for example an I section girder 68 of a barn or like structure within which the granular material is to be stored.

If the sheets 12, 14, 16, 18, 20 are steel or other similar material which is fabricated in a range of width sizes it is preferable to choose a width that is readily available in the desired length and is not too wide to make the modularity of the design unusable in many storage areas. Thus a plurality of sheets are normally required for any retaining wall and they should preferably be joined in such a manner that the strength of the wall at the joint is not substantially greater than that of the sheet material. If the joint is substantially stronger then "bulging" will occur.

For such sheet material as steel therefore a preferred form of joint is an interlocking overlapping finger arrangement as shown in Figure 4 between adjacent sheets 12 and 14 in which fingers 70 on sheet 12 overlap sheet 14 and fingers 72 on sheet 14 overlap sheet 12. An alternative possibly more preferable form of joint may be constructed by having for example sheet 12 with a plain edge and sheet 13 constructed with a series of slots such that alternate "leaves" of sheet 13 can be bent backwards and forwards to overlap sheet 12. Such an arrangement would save the cost of a machine process on one edge of each sheet.

Such an arrangement may not be necessary if a continuous sheet e.g. high tensile cloth or plastic is used to make the retaining wall.

The retaining wall formed by the high tensile sheet material is therefore relatively light compared with previous retaining wall structures. The stanchion legs 30, 32; 34, 36; and 38, 40 may be foldable into the stanchions thereby providing a compact structure for ease of storage and/or transportation. In addition because of the relative lightness of the structure the retaining wall may be more easily assembled and positioned.

The lengths X-Y and Y-Z will vary according to the characteristic of the material being stored, the frictional forces being important in determining the length Y-Z.

The sheet material may in some circumstances be pinned to the floor at an appropriate point between points Y and Z to assist in producing the correct filled profile of sheets 12 etc.

In a practical embodiment of a structure with a height of 4.2 metres and with the enclosure surcharged with grain as shown by line 64 in Figures 2 and 3 (line 64 is not necessarily shown at the correct angle) the sheet material used was type Z28 steel sheet with a thickness of less than 1 mm.

Distance Y-Z for grain was typically 2-3 metres.

Claims (8)

1. A retaining wall for retaining grain or other granular material, the wall comprising one or more sheets of high tensile material which, in use, take a curved shape which is determined by the characteristic of the retained material.

2. A retaining wall as claimed in Claim 1, in which the sheet material is steel and in which the sheets are substantially rectangular.

3. A retaining wall as claimed in Claim 1 in which the sheet material is plastic.

4. A retaining wall as claimed in Claim 1 or Claim 2, in which each sheet forming a portion of the retaining wall is supported at its upper end by a stanchion which is provided with cross bars for co-operation with a turned over upper edge of each sheet.

5. A retaining wall as claimed in Claim 4, in which the stanchions are supported prior to filling the enclosure with granular material, by one or more wire ties affixed to an appropriate part of a barn like structure within which the granular material is stored.

6. A retaining wall as claimed in any one of Claims 1, 2, 4, or 5, in which the sheets are joined in a manner such that the joint is not substantially stronger than each individual sheet.

7. A retaining wall as claimed in Claim 6, in which the sheets are joined by overlapping using an intermeshing finger arrangement.

8. A retaining wall as substantially herein described with reference to any one of the accompanying drawings.