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Title:
A SCAFFOLDING PLATFORM
Document Type and Number:
WIPO Patent Application WO/2008/013460
Kind Code:
A1
Abstract:
A platform for a scaffolding structure that includes two horizontal and parallel ledgers the platform comprising a support frame that includes at least two locators to each engage onto a respective ledger to in use hold the support frame in place; and a deck fastened to and supported by the suport frame.

Inventors:
SO YU SHING (CN)
Application Number:
PCT/NZ2007/000195
Publication Date:
January 31, 2008
Filing Date:
July 23, 2007
Export Citation:
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Assignee:
WLS INTELLECTUAL PROPERTY LTD (CN)
BLIJLEVENS ANTONIUS PETRUS HEN (NZ)
SO YU SHING (CN)
International Classes:
E04G1/15; E04G5/08
Foreign References:
JP2001214608A2001-08-10
US4825976A1989-05-02
US5141078A1992-08-25
EP0276489B21994-11-30
FR2582702A11986-12-05
Attorney, Agent or Firm:
ADAMS, Matthew, D et al. (6th Floor Huddart Parker BuildingPO Box 94, Wellington 6015, NZ)
Download PDF:
Claims:
CLAIMS

1. A platform for a scaffolding structure that includes two horizontal and parallel ledgers the platform comprising: a support frame that includes at least two locators to each engage onto a respective ledger to in use hold the support frame in place; and a deck engaged to and that in use is horizontally supported by the support frame.

2. The platform as claimed in claim 1, wherein the deck is of a different material to the support frame. 3. The platform as claimed in any one of the preceding claims, wherein the deck is made of wood and the support frame is made of a metal.

4. The platform as claimed in any one of the preceding claims, wherein the support frame includes two stringers that are parallel each other and positioned to each provide a partial frame about part of the deck. 5. The platform as claimed in any one of claims 1 to 3 wherein the deck is quadrilateral in plan shape and the support frame includes two co-planar stringers parallel each other and in a plane parallel to the deck, wherein the stringers extend parallel and are located contiguous two opposed edges of the deck and each present an edge that in plan view is positioned beyond a respective edge of the two opposed edges of the deck.

6. The platform as claimed in any one of claim 4 or 5, wherein each stringer is a "C" section channel the opening of which faces the opening of the "C" section channel of the other stringer and wherein the region of the "C" section opposite the opening includes at least one channel recess, extending into the main channel of the "C" section channel.

7. The platform as claimed in any one of the preceding claims, wherein the deck is releasably engaged to the support frame.

8. The platform as claimed in any one of the preceding claims, wherein the deck is hingeably engaged to the support frame to allow it to function as a hatch.

9. The platfoirm as claimed in any one claims 1 to 7 wherein the deck is hingeably engaged to the support frame to allow it, in use, to move between a horizontal position and a vertical position.

10. The platform as claimed in any one of the preceding claims, wherein the deck is hingeably engaged by at least one hinge positioned between the deck and the support frame.

11. The platform as claimed in claim 10, wherein the or each hinge includes one hinge part engaged to the support frame and another hinge part engaged to the deck, each part dis-engagable from each other. 12. The platform as claimed in any one of the preceding claims wherein the locators are hooks that can each accommodate part of a ledger and be supported thereby.

13. The platform as claimed in any one of claims 1 to 11 wherein the locators are clamps that can each clamp about a ledger and be supported thereby.

14. The platform as claimed in any one of the preceding claims, wherein the platform is secured to the scaffolding structure by a tether.

15. The platform as claimed in anyone of the preceding claims wherein the deck is directly engaged to said support frame.

16. A composite platform for a scaffolding structure comprising: a support frame made of steel; and a deck made of a non metallic material, wherein the deck is engaged to and in use is horizontally supported by the support frame.

17. The composite platform as claimed in claim 16 wherein the support frame includes at least four frame members in a substantially quadrilateral arrangement. 18. The composite platform as claimed in any one of claims 16 and 17 wherein the deck is made of wood.

19. A catwalk system for a scaffolding structure comprising: at least two platforms that each includes a support frame and a deck that is engaged to and in use is horizontally supported by the support frame at a level of the scaffolding structure, and

an intermediate deck to span between two of the at least two platforms that ate spaced apart each other.

20. A catwalk system as claimed in claim 19 wherein the intermediate deck includes a fastening means to fasten the intermediate deck with at least one of the platforms of the at least two platforms.

21. A catwalk system as claimed in claim 19 wherein the intermediate deck includes a fastening means to fasten the intermediate deck with two adjacent said platforms to span across the gap between the two platforms.

22. A catwalk system as claimed in any one of claims 19 to 21 wherein the intermediate deck is releasably fastened with at least one of the platforms of the at least two platforms.

23 A catwalk system as claimed in any one of claims 19 to 22 wherein the intermediate deck is movably engaged to one of the platforms of the at least two platforms and can move between a stored condition wherein it is parallel and contiguous to the deck of said one of the platforms and an extended position wherein it is parallel and projects away from the deck of said one of the platforms to span between adjacent said platforms.

24. A catwalk system as claimed in claim 23 wherein the intermediate deck is hingeably engaged to said one of the platforms. 25. A catwalk system as claimed in claim 23 wherein the intermediate deck is slideably engaged to said one of the platforms.

26. A catwalk system as claimed in any one of claim 19 to 25 wherein the deck of each platform is hingeably engaged to the support frame to allow it to function as a hatch. 27. A scaffolding structure that includes at least two horizontally extending and substantially parallel ledgers that support a catwalk, the catwalk defined by (i) at least two platforms spaced apart each other and that each includes a support frame engaged to and supported by said two ledgers and a horizontal deck supported by the support frame at and (ii) an intermediate deck spanning between two of the at least two platforms.

28. A scaffolding structure as claimed in claim 27 wherein the intermediate deck is fastened to at least one of the platforms of the at least two platforms.

29. A scaffolding structure as claimed in claim 27 or 28 wherein the intermediate deck is releasably fastened with at least one of the platforms of the at least two platforms.

30. A scaffolding structure as claimed in any one of claims 27 to 29 wherein the intermediate deck is movably engaged to one of the platforms of the at least two platforms and can move between a stored condition wherein it is parallel and contiguous to the deck of said one of the platforms and an extended position wherein it is parallel and projects away from the deck of said one of the platforms to span between adjacent said platforms.

31. A scaffolding structure as claimed in claim 30 wherein the intermediate deck is hingeably engaged to said one of the platforms.

32. A scaffolding structure as claimed in claim 30 wherein the intermediate deck is slideably engaged to said one of the platforms.

33. A scaffolding structure as claimed any one of claims 27 to 32 wherein the deck of each platform is hingeably engaged to its support frame to allow it to function as a hatch.

34. A scaffold structure that includes at least two horizontally extending and substantially parallel ledgers that support a platform comprising a support frame that includes at least two locators each engaged onto a respective ledger holding the support frame in place and a horizontal deck engaged to and supported by the support frame.

Description:

A SCAFFOLDING PLATFORM

FIELD OF THE INVENTION

The present invention relates to a scaffolding platform.

BACKGROUND

Scaffolding is frequently used in the building and construction industry. Platforms may be installed on the scaffoldings to create walkways for ease of movement of people on the scaffoldings. A platform usually consists of a steel sheet to define a deck and that is bent around corners to effectively create a thicker panel with improved bending strength. Hook portions may extend from the sides of the metal frame to hook over parts of the scaffolding. This is for example shown in our UK patent GB 2355752.

One disadvantage of this type of platform is that direct vertical transportation of building materials within the scaffolding cannot be conveniently carried out because such platforms are heavy to move to create openings in the scaffolding. Instead workers will waste time transporting building materials by walking up and down ladders or staircases and along platforms of the scaffolding structure. Workers could transport building materials outside the scaffolding structure but this can be unsafe. Alternatively the workers may remove the entire platform to carry out vertical transportation of building materials. Platforms can be heavy and difficult to move so this is also not a desirable option. These restrictions to vertical transportation may also affect the speed of erecting and dismantling the scaffolding.

Further, since the platform is totally made of steel and usually substantially of the same gauge of sheet metal, the platforms can be heavy and cannot be transported cheaply and easily. The folded edges provide bend strength for the platform and the gauge of the sheet is usually selected to fulfill bend strength requirements. This gauge is usually more than is required for strength of the deck portion of the platform.

Being predominantly made of a folded sheet metal of an appropriate gauge, the edges of the platform are also susceptible to indentations caused by impact from hard

objects. Such indentations can gteatly reduce the strength of the platform. A platform with a damaged edge may not be re-used for safety reasons.

It is therefore an object of the present invention to provide a platform which overcomes or at least ameliorates some of the abovementioned disadvantages or which at least provides the public with a useful choice.

BRIEF DESCRIPTION OF THE INVENTION

In a first aspect the present invention consists in a platform for a scaffolding structure that includes two horizontal and parallel ledgers the platform comprising: a support frame that includes at least two locators to each engage onto a respective ledger to in use hold the support frame in place; and a deck engaged to and that in use is horizontally supported by the support frame.

Preferably the deck is of a different material to the support frame. Preferably the deck is made of wood and the support frame is made of a metal.

Preferably the support frame includes two stringers that are parallel each other and positioned to each provide a partial frame about part of the deck.

Preferably the deck is quadrilateral in plan shape and the support frame includes two co-planar stringers parallel each other and in a plane parallel to the deck, wherein the stringers extend parallel and are located contiguous two opposed edges of the deck and each present an edge that in plan view is positioned beyond a respective edge of the two opposed edges of the deck.

Preferably each stringer is a "C" section channel the opening of which faces the opening of the "C" section channel of the other stringer and wherein the region of the "C" section opposite the opening includes at least one channel recess, extending into the main channel of the "C" section channel.

Preferably the deck is releasably engaged to the support frame.

Preferably the deck is hingeably engaged to the support frame to allow it to function as a hatch. Preferably the deck is hingeably engaged to the support frame to allow it, in use, to move between a horizontal position and a vertical position.

Preferably the deck is hingeably engaged by at least one hinge positioned between the deck and the support frame.

Preferably the or each hinge includes one hinge part engaged to the support frame and another hinge part engaged to the deck, each part dis-engagable from each other.

Preferably the locators are hooks that can each accommodate part of a ledger and be supported thereby.

Preferably the locators are clamps that can each clamp about a ledger and be supported thereby. Preferably the platform is secured to the scaffolding structure by a tether.

Preferably the deck is directly engaged to said support frame.

In a further aspect the present invention consists in a composite platform for a scaffolding structure comprising: a support frame made of steel; and a deck made of a non metallic material, wherein the deck is engaged to and in use is horizontally supported by the support frame.

Preferably the support frame includes at least four frame members in a substantially quadrilateral arrangement. Preferably the deck is made of wood.

In a further aspect the present invention consists in a catwalk system for a scaffolding structure comprising: at least two platforms that each includes a support frame and a deck that is engaged to and in use is horizontally supported by the support frame at a level of the scaffolding structure, and an intermediate deck to span between two of the at least two platforms that are spaced apart each other.

Preferably the intermediate deck includes a fastening means to fasten the intermediate deck with at least one of the platforms of the at least two platforms.

Preferably the intermediate deck includes a fastening means to fasten the intermediate deck with two adjacent of said platforms to span across the gap between the two platforms.

Preferably the intermediate deck is releasably fastened with at least one of the platforms of the at least two platforms.

Preferably the intermediate deck is movably engaged to one of the platforms of the at least two platforms and can move between a stored condition wherein it is parallel and contiguous to the deck of said one of the platforms and an extended position wherein it is parallel and projects away from the deck of said one of the platforms to span between adjacent said platforms.

Preferably the intermediate deck is hingeably engaged to said one of the platforms.

Preferably the intermediate deck is slideably engaged to said one of the platforms. Preferably the deck of each platform is hingeably engaged to the support frame to allow it to function as a hatch.

In a further aspect the present invention consists in a scaffolding structure that includes at least two horizontally extending and substantially parallel ledgers that support a catwalk, the catwalk defined by (i) at least two platforms spaced apart each other and that each includes a support frame engaged to and supported by said two ledgers and a horizontal deck supported by the support frame at and (ϋ) an intermediate deck spanning between two of the at least two platforms.

Preferably the intermediate deck is fastened to at least one of the platforms of the at least two platforms. Preferably the intermediate deck is releasably fastened with at least one of the platforms of the at least two platforms.

Preferably the intermediate deck is movably engaged to one of the platforms of the at least two platforms and can move between a stored condition wherein it is parallel and contiguous to the deck of said one of the platforms and an extended position wherein it is parallel and projects away from the deck of said one of the platforms to span between adjacent said platforms.

Preferably the intermediate deck is hingeably engaged to said one of the platforms.

Preferably the intermediate deck is slideably engaged to said one of the platforms. Preferably the deck of each platform is hingeably engaged to its support frame to allow it to function as a hatch.

In a further aspect the present invention consists in a scaffold structure that includes at least two horizontally extending and substantially parallel ledgers that support a platform comprising a support frame that includes at least two locators each engaged onto a respective ledger holding the support frame in place and a horizontal deck engaged to and supported by the support frame.

Other aspects of the invention may become apparent from the following description which is given by way of example only and with reference to the accompanying drawings. As used herein the term "and/ or" means "and" or "or", or both.

As used herein "(s)" following a noun means the plural and/or singular forms of the noun.

The term "comprising" as used in this specification and claims means

"consisting at least in part of. When interpreting statements in this specification and claims which include that term, the features, prefaced by that term in each statement, all need to be present but other features can also be present. Related terms such as

"comprise" and "comprised" are to be interpreted in the same manner.

The entire disclosures of all applications, patents and publications, cited above and below, if any, are hereby incorporated by reference. To those skilled in the art to which the invention relates, many changes in construction and widely differing embodiments and applications of the invention will suggest themselves without departing from the scope of the invention as defined in the appended claims. The disclosures and the descriptions herein are purely illustrative and are not intended to be in any sense limiting.

BRIEF DESCRIPTION OF THE DRAWINGS

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

Figure 1 is a perspective view of a scaffolding structure adjacent a building,

Figure 2 is a side view of a scaffolding structure adjacent a building, Figure 3 is a partially exploded view of a platform for use with a scaffolding structure,

Figure 4 is a perspective view of a variation to the platform of Figure 3,

Figure 5a shows an end view of part of a platform illustrating a variation to the locator, Figure 5b shows an end view of part of a platform illustrating another variation to the locator,

Figure 6 is a perspective view of a support frame as a variation to that shown in Figure 3,

Figure 7 illustrates two platforms in situ, Figure 8 illustrates two platforms in situ and an intermediate deck engaged therewith,

Figure 9 is a front view of part of a scaffolding structure and two platforms adjacent each other,

Figure 10 is a cross-sectional view of section Y-Y of Figure 3, and Figure 11 is an alternative cross-sectional view of Y-Y of Figure 3.

DETAILED DESCRIPTION OF THE INVENTION

With reference to Figure 1 there is shown a scaffolding structure 1. The scaffolding structure may consist of a plurality of upright standards 2 and a plurality of ledgers 3. Connectors 4 may connect what may generally be defined as an inner and outer grid 5 and 6 of upright standards 2 and ledgers 3. The inner grid 5 is proximate more the building 7 and the outer grid 6 is distal more from the building 7. Most commonly the scaffolding structure 1 will consist of pairings of ledgers 3 in each of the inner and outer grids that are substantially parallel and at the same horizontal level as each other. Such ledgers 3 preferably extend horizontally in their longitudinal direction.

Figure 2 shows that both the inner and outer grids may also be connected by a connector 8 to the building 7.

The platform 9 is in one form for example shown in Figure 3. The platform 9 is preferably of a composite construction and consists of a support frame 10 and a deck 11. The platform 9 is preferably of a quadrilateral shape in plan view and is preferably of a rectangular shape as shown with reference to Figure 3.

In the most preferred form the deck 11 is made from a different material to the support frame 10. In the preferred form the deck 11 is made from a material having a lower weight per square metre compared to the support frame 10. The support frame 10 is preferably made of a steel such as a mild steel or similar. The deck 11 is preferably made from a cellulosic material such as wood, for example in the form of a plywood. Alternatively the deck 11 may be made from a fibre board or similar.

The deck 11 is preferably made of a single sheet as shown with reference to Figure 3 or alternatively may be made from a plurality of sheets. Alternatively the deck 11 may be made from a plurality of planks or bamboo lengths that are placed adjacent each other to define a deck on which a person can stand and be supported. In yet further variations, the deck may be made from the same material or a different material as the support frame 10 and may be defined as a mesh or grate or other configuration having openings therethrough to reduce its weight per square metre. The preferred rectangular deck 11 includes a pair of major opposed edges 12 and 13 and a pair of minor opposed edges 14 and 15. In the most preferred form at least the major opposed edges 12 and 13 sit inward from a peripheral edge of the support frame 10 defined by its longitudinal stringers 16 and 17. Preferably also the minor opposed edges 14 and 15 sit inward of a peripheral edge of the support frame 10 defined by the end members 18 and 19 of the support frame 10. However in alternative forms such as the support frame 110 shown with reference to Figure 6, the longitudinal stringers 116 and 117 may be provided to be positioned inward of the major opposed edges 12 and 13. Indeed the end members 118 and 119 of the support frame may also or alternatively be inward of the perimeter of the minor edges 14 and 15 of the deck ll.

In the most preferred form however die longitudinal stringers 16 and 17 are positioned at least in part outside of the perimeter of the opposed edges 12 and 13 to offer improved durability to the platform 9 of the present invention. The longitudinal stringers 16 and 17 are preferably of a configuration that is sufficiendy resilient to common impact damage that might occur on a construction site or during their handling and/or transport. The wall thickness and/or shape of the longitudinal stringers 16 and 17 is preferably of a kind to not have its structural integrity and strength significantly affected by for example the dropping of the platform on the ground or landing of certain objects onto the stringer to thereby affect the strength of the platform 9.

The preferred stringer has a cross-sectional view as shown in Figure 10. The stringer is generally a "C" section and includes a channel 164. There is an opposing longitudinal channel 161 provided in this "C"-shaped beam. The opposing longitudinal channel 161 is provided to improve strength against bending in a direction towards the opening of the support frame as per direction "A" of Figure 10. An alternative embodiment of the cross-sectional view of the stringer is shown in Figure 11. In Figure 11, there are two opposing longitudinal channels 162 and 163 provided. Other cross- sections which provide improved strength against bending are also possible. The provision of stringers of a kind that have such characteristics can allow for other parts of the platform 9 to be made from a lighter material or of a material less resilient to such impact damage. This can allow for a platform of a lighter construction to be defined. Whilst less common but also possible to take into account, impact damage on the end members 18 and 19 can be accounted for in a similar manner.

In the example of the frame 110 as shown in Figure 6 where the longitudinal stringers 116 and 117 are inward of the perimeter of the deck 11 defined by the opposed major edges 12 and 13, any objects that might fall onto the edge of the platform 9 will only damage the deck 11 rather than the support frame 110. Therefore such a configuration can also ensure that the structural strength of the platform 9 is not adversely affected as a result of objects impacting on an edge of a platform 9. Figure 3 shows the support frame 10 may also include locators 21. In the most preferred form the support frame 10 includes four locators 21 preferably each

provided at or proximate each of the corners of the substantially rectangular or quadrilateral shaped platform 9. The locators 21 may be provided in pairs at each of the end members 18 and 19. One of the locators of each pair is to engage with a first ledger 3 of for example the inner grid 5 and the other locator 21 is to locate onto a ledger 3 of for example the outer grid 6 as for example shown in Figure 8. The locators 21 are preferably of a kind to locate onto a respective ledger to thereby gain support from the ledger 3 to hold the platform in a stable position relative to the scaffolding structure 1. The locators 21 as herein described may include a further lock component 46 (Figure 5a) that may allow for releasable locking engagement to occur of the platform 9 with a respective ledger at the locator 21. This may offer a further secure engagement of the platform 9 to ensure that it cannot be dislodged undesirably from part of the scaffolding structure. An alternative embodiment of the locking component is shown in Figure 5b. The locking arm 47 can slide to engage the platform 9. This may occur by means of gravitational force. In the most preferred form in situ, the ledgers 3 of the inner and outer grids onto which the locators 21 are positioned are presented to be outside of the perimeter of the deck 11 defined by its major opposed edges 12 and 13. However in alternative configurations the opposed edges 12 and 13 may sit beyond one or both of the ledgers 3 of the inner or outer grid 5, 6. Such is not shown in the accompanying drawings. In Figures 7 and 8 the pair of ledgers 3 of the inner and outer grid and with which locators 21 of a platform 9 are located, are substantially in the same horizontal plane as each other.

The deck 11 is preferably releasably engaged to the support frame 10. It can preferably be fastened by the use of fasteners 26 to the support frame. This allows for the platform 9 to be disassembled in order to break it down into more manageable ports. This may make the platform more convenient for transportation or handling. The fasteners 26 may be bolts that can extend through the deck 11 to locate with part of the support frame 10 beneath the deck 11.

With reference to Figure 4, there is shown a variation where the platform 309 consists of a support frame 310 that may be of a kind as shown with reference to Figure 3 or 6 or similar and wherein the deck 311 is hingeably engaged to the support

frame 310. Such hingeable engagement may be provided by a hinge of hinges 336 that define an axis of rotation XX of the deck 311 with the support frame 310. The hinge can allow for the deck 311 to rotate between a position where it is substantially parallel with the generally planar nature of the support frame 310 (wherein it is fully supported on or by the support frame 310) and a vertical position (wherein the support frame 310 is substantially fully exposed by the deck 311). In any position between the completely horizontal position of the deck 311 and the vertical position of the deck 311 an opening can be created through the platform to allow for the passage of items through the platform 309. This can be an advantage in that materials such as building materials or tools can be transported up in between the inner and outer grids 5 and 6 of the scaffolding without interference from the platforms that may be engaged with the scaffolding.

The platform as shown with reference to Figures 3 and 7 and 8 can also allow for such openings to be created through the platform upon the removal of the deck 11 once the fasteners 26 have been removed for their disengagement with the support frame 10.

The hinge or hinges 336 shown with reference to Figure 4 may be of a kind diat will allow for pivotal engagement of the deck 311 relative the support frame 310 and may also allow for a disengagement of die deck 311 with the support frame 310. Accordingly the support platform 309 shown with reference to Figure 4 can allow for a convenient creation of an opening and also a convenient breakdown of the support platform for transportation and/or handling purposes whereby the support platform 309 can be defined substantially in its two major component parts being the deck 311 and the support frame 310. The platforms herein described may also carry a toe board (not shown) that can be provided as a safety feature to the platform.

A tether 14 may be used to establish a connection between the platform 9 and a ledger 3 or the like to ensure that any dislodgement of the platform 9 with its ledgers will not result in the platform 9 from tumbling down the scaffolding structure. Figure 8 shows a catwalk 50 that comprises of a plurality of platforms 9. The catwalk 50 consists of a series of platforms 9 positioned to define a catwalk to the

scaffoldiαg structure 1. The catwalk 50 consists of a plurality of platforms 9 positioned in series to in effect define a larger horizontal working surface and deck. Each of the decks 11 of the platforms 9 placed in series are substantially in the same horizontal plane. In one version of the catwalk 50 an intermediate deck 51 may be positioned to span across any gap between adjacent platforms 9. The intermediate deck 51 may include apertures to allow for die fasteners 26 that engage the decks 11 of the respective support platforms to their respective support frames to also be fastened thereby. In this manner a catwalk can be defined wherein the support platforms 9 do not need to define the entire working surface but wherein such an intermediate panel 51 (with not necessarily all or any of the support features provided underneath) can be provided. This can save time and reduced handling weight in erecting a catwalk 50. It can also reduce the overall weight of the catwalk 50.

In the example shown with reference to Figure 8, the intermediate deck 51 sits on top of the decks 11 of the platforms 9. However alternatively each of the platforms 9 may include a ledge onto which the intermediate deck 51 can be positioned so that it can sit flush with the upper surfaces of the decks 11 of its adjacent platforms 9.

With reference to Figure 9 there is shown a variation to the catwalk 50 wherein one or both of the adjacent platforms 9 may carry two decks, a first deck 11 and a second deck 411. The second deck 411 may be pivo tally engaged at a hinge or hinges 463 that can allow for the second deck 411 to engage relative the first deck 11. The first deck 11 is of the kind as hereinbefore been described but may have hingeably engaged thereto the second deck 411 to allow for the second deck to move between a stored position as shown in Figure 9 to an extended position shown in phantom in Figure 9 wherein it can span the gap 73 intermediate of the two adjacent platforms 9. The second deck 411 may alternatively be engaged to another part of the support platform such as for example the support frame 10 or other portion thereof. In this manner a convenient opening can be created when and where necessary to allow for the transportation of items up and down through the scaffolding structure intermediate of the inner and outer grids. The second deck 411 can be folded to its stored position to create such an opening across die gap 73 between adjacent support platforms 9.