EP2978902A1

EP2978902A1 - A shuttering support and related system

Info

Publication number: EP2978902A1
Application number: EP14715379.5A
Authority: EP
Inventors: David John MOORE
Original assignee: David J Moore Ltd
Current assignee: David J Moore Ltd
Priority date: 2013-03-27
Filing date: 2014-03-20
Publication date: 2016-02-03
Also published as: WO2014155034A1; GB201518651D0; GB2527472C; GB2527472B; GB2527472A; GB201305604D0; GB2512348B; GB2512348A

Abstract

The present invention provides a support and a system for bracing and supporting the sides of trenches, excavations or embankments. The system comprises a plurality of elongate plank elements and at least one main shuttering support. Each main shuttering support has an inner wall arranged in use to extend substantially vertically, and a ground pinning element extending from a rear face of the inner wall which is arranged in use to extend substantially horizontally and remain in contact with the ground. A front face of the inner wall defines a plurality of vertically aligned slots. Each slot is shaped and dimensioned to receive the elongate plank element. The system further comprises an elongate upper side brace and an elongate lower side brace, said side braces comprising a connection mechanism for engaging each side brace and at least two plank elements, so that in use, the side braces are aligned to extend substantially horizontally and with the inner wall, one side brace extending above the other side brace.

Description

A SHUTTERING SUPPORT AND RELATED SYSTEM

Field of the Invention The present invention relates to a shuttering and shoring support for use in a shuttering system for supporting side walls of excavations such as trenches, ditches or excavations of embanked areas.

Background

Subsurface utilities such as drains, water pipes, cables and sewers often need to be accessed at intervals for repair, maintenance and upgrading. Utilities such as pipes, drains and cables often extend for long, unbroken stretches, often below walkways or roads. In order to access these utilities it is often necessary to dig up or otherwise excavate an area of ground either side of the utility and this excavation usually extends into the road or walkway.

Utilities can be located some distance below the surface of the road or walkway. In order to minimise inconvenience for road users or pedestrians, and to keep post-operation work to a minimum and as tidy as possible, the hole or excavation is ideally dug with vertical or near-vertical sides. In order to prevent accidents such as the sides collapsing into the hole, the sides are reinforced or braced. Conventionally sides were reinforced or braced by using planks disposed vertically, scaffolding poles and ancillary items such as scaffolding fasteners, nails and devices known as acrow prop which buttresses the vertical planks. This process and related equipment was known as shuttering. Assemblage or construction of the shuttering is a reasonably complicated task, involving the assembly of several separate items in a specific order. A typical excavation requires 40 to 50 planks, each approximately 2 metres in length. Also, it is usual practice to discard timber planking after use for safety reasons. This is wasteful and increases the overall cost of excavations.

Prior Art

A number of solutions have been proposed which aim to improve upon drawbacks of existing shuttering systems and some of these are described in in the following: European Patent Application EP-A-1 193 350 (Emunds & Staudinger GmbH) discloses a device for shoring up deep ditches which utilises paired vertical supports equally spaced along the ditch and opposite to one another. The supports are fitted on spaced bracing frames which are vertically displaceably connected to them.

European Patent Application EP-A-678 629 (Wilhelm Hess) describes a device for supporting the walls of a ditch, and comprises paired opposing vertical supports arranged at equal distances along the ditch, with bracing devices holding the supports of a pair spaced apart.

UK Patent Application GB-A-2 270 938 (Hesc Bastion Limited) describes a collapsible earth trench support structure having side panels for application to the sides of trench walls pivotally connected to cross bars for jacking the sides apart and onto the trench walls.

UK Patent Application GB-A-1 419 071 (Hudswell Morris Limited) discloses a piling system which is adapted to be supported on a fame and moved across the ground for the purposes of inserting a removing a pile. US Patent US-B-6 224 296 (Fukumori) discloses a trench shoring system that uses panels to prevent collapse of side walls of the ground. The panels offering increased safety and efficiency. UK Patent Application GB-A-1 217 527 (Gebr. Jost AG) describes a bracing system for use in excavations which includes a movable carriage which is arranged to advance in a stepwise fashion with the progress of th4e excavation.

It is an object of the present invention to provide a shuttering support and system for supporting the side walls of excavations which overcomes disadvantages associated with existing shuttering systems so as to provide users with a useful choice of solutions.

Summary of the Invention

According to the present invention there is provided a shuttering support for use with a shuttering system for bracing and supporting sides of trenches or excavations, the shuttering support comprising: an inner wall having a vertical surface which, in use, abuts against a vertical side of the trench or excavation; and a ground pinning element that extends substantially horizontally from the inner wall, a receiving means is located adjacent the inner wall and is arranged to receive an elongate plank element so as to permit vertical movement of the elongate plank element, with respect to the inner wall.

Ideally the shuttering support has a means to restrict lateral movement of the elongate plank element, with respect to the inner wall. The receiving means is preferably a slot defined by a frame and is vertically aligned so as to permit vertical movement of the elongate plank element and dimensioned so as to restrict lateral movement of the elongate plank element, with respect to the inner wall. Ideally the frame that defines the slot is formed integrally with the support. The support may be used with planks so as to support an excavation on a hillside or embankment for example. When used in combination with another shuttering support a shuttering system is provided for bracing and supporting the sides of trenches or excavations, the system comprising: a plurality of elongate plank elements; at least one main shuttering support, each main shuttering support having an inner wall arranged in use to extend substantially vertically, a ground pinning element extending from a rear face of the inner wall in which said ground pinning element is arranged in use to extend substantially horizontally and in which a front face of the inner wall provides a plurality of vertically aligned slots, wherein each slot is shaped and dimensioned to receive an elongate plank element, and at least an elongate upper side brace and an elongate lower side brace, said side braces comprising a connection mechanism for engaging each side brace to at least two plank elements, wherein in use, the side braces are aligned to extend substantially horizontally and with the inner wall, one side brace extending above the other side brace.

Optionally the inner wall may have drainage apertures (slots or holes) formed therein to prevent water from building up behind the inner wall.

The use of a shuttering support and side braces allows the shuttering system to be installed by hand and on many occasions without the need to use machines, and allows the planks to be aligned and located easily and correctly.

Preferably the connection mechanism is a brace locator. Preferably at least two brace locators are removably connected to each side brace at two spaced points.

Preferably, the planks and brace locators are therefore adapted for mutual connection. The use of a brace locator makes it easier to connect the braces to the planks and also increases the overall strength and stability of the system. In embodiments requiring longer planks a greater number of braces may be utilised. Ideally each plank provides a plurality of locator holes along its length. The brace locator may comprise a locator pin. The pin may be shaped and dimensioned to be received within a locator hole. The use of locator holes makes it easier to locate the brace locator in use, and also increases the overall strength and stability of the system as the pin is less likely to slip and therefore less force is required to keep it in position.

Optionally planks may have drainage apertures (slots or holes) formed therein to prevent water from building up behind the inner wall.

Preferably the ground pinning element comprises a grid that extends outwards from the rear face of the inner wall. Advantageously the ground pinning element is arranged in use to extend substantially horizontally from the rear face of the inner wall. The inner wall may comprise a grid work or lattice of struts arranged in order to define an array of slots or aligned holes. The array of slots or holes is ideally aligned vertically. The slots or holes so arranged are shaped and dimensioned to receive ground pins, pegs or similar securing devices so as to position the shuttering support in position. Use of such a gridwork of struts helps maintain the shuttering support system lightweight and facilitates use on uneven surfaces. In a particularly preferred embodiment, ground pinning elements are hingeably connected to the inner wall, so that the hinged arrangement allows ground pinning elements to fold into spaces defines between struts and this also allows the shuttering support to be carried easily.

Preferably a shuttering system comprises two shuttering supports arranged to face one another in an excavation or ditch. Each shuttering system may have an associated upper and lower side brace. The shuttering system may further comprise a plurality of cross braces of adjustable length. The cross braces may be positioned to run substantially horizontally across the gap between the shuttering supports. Cross braces may be rigid (for use below ground level) or flexible (for use above ground level), so as to prevent walls from collapsing inwards or ends of planks, on opposite sides from moving apart.

In use, the two main shuttering supports, their associated upper and lower side braces and planks located directly opposite one another with their front faces facing one another, each of the upper and lower side braces connected at the same height as the other, the cross braces positioned to run substantially horizontally across the gap between the shuttering supports, so that one of each of the ends of the cross braces is placed against a side brace.

The length of cross braces is ideally adjustable, to suit different widths of trenches, so that the ends of the brace press outwards against the side braces. Use of cross braces allows paired shuttering supports to be positioned one on each side of a trench or excavation to support opposed walls.

Preferably the side braces provide a plurality of cross brace locator holes.

Each end of each side brace may provide a cross brace locator pin that is shaped and dimensioned to be received within a cross brace locator hole.

Alliteratively cross braces may be threaded or fitted with a ratchet extender.

In exceptional circumstances cross braces may be hydraulically powered.

These locator holes allow the ends of the cross braces to be located in the inner wall and this ensures forces are transmitted across a framework defined by the erected structure, so making the structure less prone to movement, more stable and ensures that less overall force is required to keep the structure rigid and stable.

Preferably the side braces, planks and main shuttering supports are formed from steel coated in UV stabilised paint. Optionally the support may be fabricated from a lightweight rigid synthetic plastics material. Suitable safe weight and safe operating depth of trench information may be marked on the support for health and safety purposes. The side braces, planks and main shuttering supports may be formed from aluminium coated, for example aluminium coated in UV stabilised paint. Preferably one end of each inner wall has an associated male connector and the other has an associated female connector, the male and female connectors mutually adapted so that a row of main shuttering supports can be connected by their edges. This allows an unbroken row of inner walls to be formed to the appropriate length for any particular excavation. Ideally said inner walls are arranged in use to extend above ground level, so as to minimise in-falling or articles into the shuttered excavation.

Preferably the shuttering system further comprises a plurality of fence elements for fixing to the system in order to prevent persons form inadvertently walking into an excavation or trench. Each fence element optionally comprises a pair of legs extending downwards one from each end of a fence board.

The inner wall optionally includes a plurality of attachment means, such as clips or connectors, or apertures or holes sized and shaped to receive lower ends of the legs. A row of fence elements can be detachably connected along length of the inner wall. Advertising panels, guard rails, lighting fixtures, guides for cabling or other features, may be fitted to the fencing elements. Optionally the shuttering system further comprises a cover. The fence elements and/or cover may be adapted so that the cover can be connected to the fence elements.

The plank elements may be of any suitable length, preferably the plank elements are around 2.0 to 2.5 metres in length.

The distance between edges of each slot defined between adjacent planks may be any suitable distance; preferably the maximum distance between the edges of each slot is substantially 15mm. However, it will be appreciated that the gap may be slightly larger or smaller.

The invention will now be described, by way of example only, with reference to the accompanying drawings in which:

Brief Description of the Figures

Figure 1 shows an embodiment of a shuttering support that forms part of the shuttering system of the present invention;

Figure 2 shows an example of plank for use with the shuttering system of the present invention; Figure 3 shows an adjustable cross brace for use with the shuttering system of the present invention;

Figure 4a shows an exploded view of the shuttering system; Figure 4b shows an overall view of the assembled system in Figure 4a;

Figure 5 shows a diagrammatical view of a shuttering support system in situ supporting opposite walls of an excavation or trench; Figure 6 shows a diagrammatical view of an alternative embodiment of shuttering support system, depicting cross-brace and a safety chain;

Figure 7 shows in greater detail the slot that receives and retains the plank in contact with an inner wall of the shuttering support;

Figure 8 shows a part exploded view of a plank, located in a slot, and held in contact with an inner wall of the shuttering support; Figure 9 shows an alternative embodiment of a shuttering support with foldable ground pinning elements or tines extended;

Figure 10 shows the shuttering support of Figure 6a with the foldable ground pinning elements or tines folded to facilitate transportation; and

Figure 11 shows a diagrammatical part-sectional view illustrating how a single support can be used to buttress a hillside, embankment or viaduct. Detailed Description of the Invention

Referring to the Figures generally and specifically to Figures 1 to 4, a shuttering system is used to support or brace substantially vertical side walls of trenches or similar excavations. A number of different elements are used to form the shuttering system of the present invention. These are described below.

The shuttering system has at least one and preferably a plurality of shuttering supports 1. Each shuttering support 1 is formed so that when viewed end on, it has an X-shaped cross-sectional form, with a vertical face or inner wall that abuts a vertical side of the trench or excavation and a horizontal ground pinning arm(s) or tines extending substantially horizontally from the inner wall; and a brace that receives an elongate plank element. The shuttering support has a substantially vertical inner face or wall 2. The ground pinning elements or tines 3 extend outwards from the rear face of the inner wall 2, substantially horizontally. The brace is typically defined by a plurality of vertically aligned slots 4 extending from the front face of the inner wall 2, preferably at the same height as the ground pinning element, although this is not essential.

The shuttering system 1 , when erected includes a plurality of plank elements or planks 5. The planks 5 and the slots 4 are matched in size so that the aperture(s), defined by the slots in the braces, match(es) the cross sectional end size and shape of the planks 5. In use, the planks 5 are pushed end first through the slots 4 to locate into the slots 4, so as to form a row of vertically aligned planks 5 along the inner face of the inner wall 2 and extending downwards into the trench or excavation.

The preferred form of planks 5 are of the order of between 1 to 3 metres in length. Ideally a small gap is defined between adjacent planks and it is preferred that the maximum distance between the edges of each slot is substantially 15mm. This permits space for expansion/contraction of adjacent planks as well as egress of water and permits some lateral movement when fitting and removing the planks.

The shuttering system further has an elongate upper side brace 6 and an elongate lower side brace 7. The side braces 6, 7 are in use connected to the row of planks 5 at least at two different points or locations along the row of planks, so that the side braces are aligned substantially horizontally and substantially aligned with the inner wall. The upper side brace 6 is directly above and spaced from the lower side brace 7.

In the preferred embodiment shown in Figures 4a and 4b, the connection mechanism is a brace locator 8. At least two brace locators 8 are removably connected to each side of each brace 6, 7 at two spaced points. It is preferred that the side braces 6, 7 are rectangular in cross-section, and that the connection mechanism is a substantially C-shaped element that slips over the end of the side brace 6, 7. Although it will be appreciated that other shaped elements and engagement systems may be used.

Each of the planks 5 preferably has a plurality of locator holes along its length. The brace locator has a locator pin on its rear face. The locator pin fits into a locator hole in use to locate the brace 6, 7 in position against the plank 5. The ground pinning element 3 is preferably a grid that extends outwards from the rear face of the inner wall 2, the grid extending far enough to stabilise and anchor the main shuttering support 1 in use. The grid preferably has a number of vertically aligned holes 9 passing vertically through it to allow ground pins or pegs 10, or similar to be passed through the holes to pin the shuttering system in position.

In use, a pair of shuttering supports 1 are positioned one on each of opposed sides of a trench or excavation, their associated upper and lower side braces 6, 7 and planks 5 located directly opposite one another with their front faces facing one another, each of the upper and lower side braces 6, 7 connected at the same height as the other. The shuttering system further has a plurality of cross braces 11 , of adjustable length. In use, the cross braces 11 are positioned to run substantially horizontally across the gap between the shuttering supports, so that one of each of the ends of the cross braces is placed against a side brace.

Once in position, the length of the cross braces 11 is adjusted so that the ends of each brace 11 press outwards against the side braces 6, 7. This pushes each of the shuttering supports outwards or away from one another against the walls of the trench or excavation, thereby supporting the walls against collapse.

It is most preferred that the side braces 6, 7 have a plurality of cross brace locator holes 12, and that each end of each side brace 6,7 has a cross brace locator pin that in use locates into a cross brace locator hole. Ideally the cross brace locator holes are offset towards the longer side edge of the plank 5 so that the distance between adjacent ones of the cross braces can be slightly larger than otherwise. This gives greater space where necessary in the trench or excavation.

Referring to Figures 4a and 4b there is shown another embodiment of the present invention with two opposed rows of main shuttering supports, associated vertically aligned planks 5, each opposed row of shuttering supports and planks 5 having an associated upper side brace and lower side brace, running horizontally along the inner faces of the planks. The upper side brace is positioned above the lower side brace and a number of adjustable length cross braces are depicted running between opposed rows of planks to hold them in position.

In the preferred form, the side braces, planks and main shuttering supports are formed from aluminium or steel coated in UV stabilised paint or reinforced injection synthetic moulded plastics material. It is preferred that the paint is brightly coloured to aid in recognition and location of a potential hazard. Optionally different sides of the planks may be coloured differently in order to present a different surface to the interior of the trench. As described above, two or a pair of main shuttering supports are located with one shuttering support opposite the other so the inner faces or walls of each shuttering support face each other. Each of the main shuttering supports may be formed to the length required - e.g. having two slots, three slots, four slots or more as required. However, excavations are of different sizes and lengths, and it is preferred that a number of main shuttering supports can be placed end to end along each wall to provide the necessary length of support. To facilitate this one end of each inner wall has an associated male connector 13 and the other end has an associated female connector 14. The male and female connectors 13, 14 are mutually adapted so that a row of main shuttering supports can be connected by their edges to form an unbroken row of the required overall length.

In the most preferred form, the shuttering system further has a plurality of fence elements 15, each comprising a pair of legs extending downwards one from each end of a fence board aligned large faces inwards/outwards. The top edge of the inner wall has a plurality of holes sized and shaped to receive the lower ends of the legs, such that a row of fence elements can be detachably connected along length of the inner wall by slotting the legs into the holes.

Optionally, the shuttering system can further have a cover, the fence elements and cover mutually adapted so that the cover can be connected over the fence elements to provide a cover over the top of the trench or excavation, and some shelter for any personnel working in the trench.

Figure 5 shows a diagrammatical cross-sectional view of a shuttering support system in situ supporting opposite walls of an excavation or trench. Left 70 and right 71 hand side inner walls are cross-braced with a lower akro 72. A second akro 74 is positioned above ground level and acts to counteract any pivotal moment applied on the lower portion of the planks, so urging them tightly against the inner sides of the trench of walls. This upper akro 74 and lower akro 72 act to serve the same purpose as the cross braces 11 , 111 also described herein.

Figure 6 shows a diagrammatical view of an alternative embodiment of shuttering support system. A first shuttering support 1 is placed on the left bank of a trench and a second shuttering support 1 is placed on the right bank of a trench. A cross-brace 1 1 presses the first shuttering support against the left bank and the second shuttering support against the right bank by pressing against both shuttering supports so as to press them apart. Preferably the cross-brace 1 11 is located at substantially the same height as the rim of the bank as shown in Figure 6. A flexible connector 112 in the form of a safety chain is connected to the first and second shuttering supports above the cross-brace. The flexible connector, such as a chain or rope, connects either the shuttering supports one to another; or ends of planking elements that sit proud of ground level. When the system is deployed across a trench or excavation, the flexible connectors are held taut and resist relative inward movement of lower ends of planking elements 5, so reducing the risk of collapsing sidewalls. An advantage of this arrangement of cross-brace 111 and flexible connector 1 12 is that the trench is kept clear of cross braces so leaving open space for people and machinery in the trench.

Referring now to Figures 7 and 8, there is shown in Figure 8 a part exploded view of a plank 5, located in a slot defined by the inner wall and a belt or brace. The plank is held in contact with the inner wall of the shuttering support and is able to move in the direction of arrow X. Figure 7 shows in greater detail the slot that receives and retains the plank 5 in contact with an inner wall of the shuttering support. The slot may be in the form of a U- shaped belt or brace defining an aperture with the support wall. It may be welded onto the support wall or formed integrally therewith.

Referring now to Figures 9 and 10, Figure 9 shows an alternative embodiment of a shuttering support 101 with foldable ground pinning elements or tines 50 extended. The ground pinning elements or tines 50 are mounted on a hinge 55 which permits them to fold into recess 60 defined in the inner wall. Figure 6b shows the shuttering support of Figure 10 with the foldable ground pinning elements or tines 50 folded into recesses 60 of the inner support wall to facilitate stowage or transportation.

Figure 11 shows how a single shuttering support can be deployed to buttress a hillside, embankment or viaduct. A structural member 33 is connected to the ground and the shuttering support. The structural member holds the shuttering support in position against the hillside so as to prevent the hillside from collapsing. The inner wall comprises a structural member connector to connect to the angled support.

The shuttering system described above can be installed by hand and does not require machinery to aid in installation.

With respect to the above description then, it is to be realised that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention.

The invention has been described by way of examples only. Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the claims.

It will be appreciated that variation may be made to the above-mentioned embodiments without departing from the scope of invention.

Claims

1. A shuttering support for use with a shuttering system for bracing and supporting sides of trenches or excavations, the shuttering support comprising: an inner wall having a vertical surface which, in use, abuts against a vertical side of the trench or excavation; and a ground pinning element that extends substantially horizontally from the inner wall, a receiving means is located adjacent the inner wall and is arranged to receive an elongate plank element so as to permit vertical movement of the elongate plank element, with respect to the inner wall.

2. A support according to claim 1 has a means to restrict lateral movement of the elongate plank element, with respect to the inner wall.

3. A support according to claim 1 or 2 wherein the receiving means is a slot defined by a frame and is aligned so as to permit vertical movement of the elongate plank element with respect to the inner wall, and dimensioned so as to restrict lateral movement of the elongate plank element, with respect to the inner wall.

4. A support according to claim 3 wherein the slot is defined by a front face of the inner wall and a connector so as to provide for a slot thickness and width matching the elongate plank(s).

5. A support according to any of claims 1 to 4 wherein the inner wall is hingeably attached to the ground pinning element with a hinge which permits the ground pinning element and inner wall to be rotated in order that they lie in the same plane.

6. A support according to claim 5 wherein the inner wall includes cutaway portions to accept the ground pinning element when collapsed.

7. A support according to any preceding claim wherein the inner wall comprises a structural member connector to connect to an structural member that is connected to the ground to as to hold the shuttering support in position.

8. A support according to any preceding claim includes at least one of the supports according to any preceding claim.

9. A shuttering system includes at least two of the supports according to any preceding claim.

10. A shuttering system according to any of claims 7 to 9 includes a connector for connecting opposing supports.

11. A shuttering system according to claim 7 to 10 wherein the connector is a rigid rod or shaft.

12. A shuttering system according to any of claims 7 to 11 wherein the connector is a continuous flexible strap or flexible cable or chain connecting planks or portions of the inner wall which stand proud of ground level.

13. A shuttering system according to any of claims 7 to 12, when dependent on claim 3, wherein the slot is dimensioned to accommodate more than one plank element arranged adjacent one another.

14. A shuttering system according to any one of claims 7 to 13 comprising a connection mechanism arranged to connect a girder to a plank element.

15. A shuttering system according to claim 14 wherein the connection mechanism includes a location device.

16. A shuttering system according to claims 14 or 15 wherein a plank element is capable of accepting a location device for securing the girder with respect to the plank element.

17. A shuttering system according to any of claims 14 to 16 wherein the plank element includes a plurality of apertures for receiving location devices at different positions along the plank element.

18. A shuttering system according to any of claims 14 to 17 wherein the girder includes at least one recess for receiving an end of a cross brace in order to fix the cross brace.

19. A shuttering system according to any of claims 7 to 18 wherein the ground pinning element includes holes or apertures adapted to receive ground pins, pegs or similar means for securing the shuttering system in position.

20. A shuttering system as claimed in any of claims 7 to 19 wherein the shuttering support comprises connectors to enable connection of one shuttering support to another.

21. A shuttering system according to claim 20 wherein the connectors include a female part at one side of the support and a male part at the opposite side so as to enable inter-engagement of one shuttering support to another.

22. A shuttering system according to any of claims 7 to 21 includes a flexible connector for use with the shuttering supports or ends of planking elements that sit proud of ground level, when the system is deployed across a trench or excavation, so as to be taut and resist relative inward movement of lower ends of planking elements.

23. A shuttering system according to any of claims 7 to 22 wherein the shuttering system includes one or more fence elements, said fence element(s) comprising a pair of legs extending downwards one from each end of a fence board adapted to be connected to a shuttering support.

24. A shuttering system according to claim 23 comprising a cover for connection to said fence elements.

25. A kit of parts comprising a plank element and a shuttering support suitable for assembly into the shuttering system defined according to any one of claims 7 to 24.

26. A shuttering support substantially as described herein with reference to the drawings.

27. A shuttering system substantially as described herein with reference to the drawings.