WO2013117196A1

WO2013117196A1 - Deck for scaffolding and method for its adaptation

Info

Publication number: WO2013117196A1
Application number: PCT/DK2013/050031
Authority: WO
Inventors: Carsten Lau KJÆRGAARD; Per Mose JAKOBSEN; Carl Bagger ØSTERVIG
Original assignee: Nordic Platform P/S
Priority date: 2012-02-06
Filing date: 2013-02-06
Publication date: 2013-08-15
Also published as: EP2812513A1

Abstract

The present invention concerns a scaffold with a deck and a method for adapting a deck to a scaffold, wherein the scaffold includes scaffolding frames - typically made of steel - as well as decks made with fixing means for fixing to the frames, wherein the fixing means at least include cutouts and/or projections, wherein at least part of the deck is made of a fibre composite material and includes at least one plate member with a top side, a bottom side, two longitudinal sides and two transverse ends. A deck according to the invention further includes two end parts, wherein the fixing means are arranged on or in the end parts, and wherein the plate member is entirely or partially made by pultrusion, having a weight between 8 and 14 kg/m2 or less, and at the same time fitting into the current scaffolding frames.

Description

DECK FOR SCAFFOLDING AND METHOD FOR ITS ADAPTATION

Field of the Invention

The present invention concerns a scaffold with a deck and a method for adapting a deck to a scaffold, wherein the scaffold includes scaffolding frames as well as decks, wherein the scaffolding frames are typically made of steel and wherein the deck is made with fixing means for fixing a deck to the frames, wherein the fixing means at least include cutouts and/or projections, wherein at least part of the deck is made of a fibre composite material and includes a at least a plate member with a top side, a bottom side, two longitudinal sides and two transverse ends.

Background of the Invention

On scaffolding of the type typically used in connection with construction or for other purposes, it is common to use perforated platforms and scaffold decks of various types.

In connection with bricklaying the perforated platforms are typically used on so-called bricklayer's scaffolds. The platforms are frequently made of wood or metal and with an open structure on the surface such that dust, lost mortar and the like largely fall through the perforated platform and therefore do not constitute any safety hazard due to weight and with regard to fall accidents. The platforms and the scaffolding as such are elevated as the bricklaying proceeds, and usually no work is done under the platforms why is it acceptable with an open structure on the surface. Platforms of wood have the disadvantage that they are heavy. A platform with a width of about 50 cm and a length of about 220 cm typically weighs 37 kg in dry condition, which is often not the case as wood easily absorbs water. It is therefore not uncommon that a perforated platform has a weight of up to 50 kg, exceeding the accepted weight in Denmark to be lifted by one person, why two persons are then required to handle these prior art types of platforms. In time, standards for accepted weights will no doubt be tightened up on in other countries. A perforated platform or scaffold deck is allowed to weigh 15 kg only according to Danish law, which has appeared to be a challenge. However, it is not only the weight that provides challenges with wooden platforms. The possibility of securing the quality of the platforms is insufficient as it is not easily determined if cracks or possibly rot are present in the platforms. However, there are platforms of aluminium on the market which are about four times as expensive and very often subject to theft as aluminium is easily sold as scrap metal. Moreover, there is the drawback that it makes a lot of noise during the work of positioning these platforms why the work is to be done with earmuffs. Therefore, there is an expressed wish as to get a new type of platforms on the market where the low weight of aluminium and the comfort with regard to noise associated with the wooden platforms are achieved. In other types of scaffolding are used the so-called scaffold decks, also called decks or planks which basically are plates forming a solid bottom on a work platform or on a scaffold of the type known from construction work, where e.g. a multi-storey building can be entirely covered by scaffolding at many storeys on one or more facades. By such a scaffolding it is possible to access facade elements and to perform work thereon. Scaffolding is usually put up with several deck layers where normally there are about 200 cm between respective decks, and where individual sections have lengths of typically 175, 250 or 300 cm, but other lengths are found on the market as well.

Common to platforms and decks is the desire for low weight - to some degree guided by present and expectations to coming requirements - and at the same time having a high robustness and wearability and ample load capacity. Moreover, it is desirable to be able to perform adaptation of perforated platforms as well as decks for specific purposes. In the following, perforated platforms as well as decks will be discussed and mentioned under the common term "deck" which then is to be understood as a general term for perforated platforms, platforms, planks, scaffold decks and decks except where otherwise stated. All these expressions are used for the plates on which a worker stands during the work on a scaffold of one or the other type. Object of the Invention

It is the object of the invention to indicate a solution with platforms and decks for scaffolds where the weight of platforms/deck is low and where at the same time it is possible to adapt the platforms and decks to a plurality of scaffolding systems such that existing scaffolds can be provided with platforms and/or decks according to the invention, and where platforms and decks can be used on equal terms with other types of platforms and decks which are adapted to respective scaffolding systems. Description of the Invention

As mentioned in the introduction and in claim 1, the invention concerns a scaffold with a deck, wherein the deck is made with fixing means for fixing a deck, wherein the fixing means at least include cutouts and/or projections, and wherein at least part of the deck is made of a fibre composite material.

The new feature of a scaffold with a deck according to the invention is that a deck further includes two end parts, each with a top side and a bottom side wherein the fixing means are arranged on or in the end parts, and that the plate member is entirely or partially made by pultrusion, having a weight between 8 and 14 kg/m² or less, alternatively with a weight between 9 and 1 1 kg/m², while at the same time fitting with current scaffolding frames.

By using fibre composite and in particular pultrusion, an exceptional good uniformity is achieved in the product and fibres can be positioned accurately and in very controlled amount/strength/type at specially selected positions in the product.

A deck for a scaffold typically has a width of about 30 or 60 cm, and lengths of about 175, 250 or 300 cm, and none of these different sizes have a weight more that 8 to 14 kg/m², or even less, when made according to the invention. This means that a deck with a width of about 60 cm and a length of about 300 cm has a weight of between 14.4 and 25 kg, and in a preferred embodiment with a thickness of the top side of just 1.5 to 2 mm, with stringers with the same thickness and with a thickness of the bottom side between 2 and 3 mm, such a deck has even lower weight which is very attractive in connection with manual handling.

Furthermore, there is achieved the advantage that a certain design of a plate member can be used for numerous types of scaffolding systems as the end parts are selected specifically for the respective scaffolding systems. It is thus possible to mount end parts that fit with scaffolding frames and other decks on a single and standardised type of plate member. In the detailed description examples of various types of fixing means on end parts for a deck according to the invention will be shown.

In a variant of a scaffold with a deck according to the invention, the plate member can advantageously be made of fibre composite, wherein the fibres are selected among glass fibres, carbon fibres, aramide fibres, polyethylene fibres, steel fibres, other plastic fibres or natural fibres, such as plant fibres or combinations of the mentioned types of fibres, and wherein the fibres are embedded in a matrix of a suitable type of plastic, e.g. polypropylene, polyester, vinyl ester, epoxy, polyurethane, or other suited type of plastic. By choosing fibres as well as matrix material according to need an appreciably reduced weight as compared with prior art types of deck can be achieved. At the same time, strongly improved properties are attained such as improved safety against skidding on the deck, higher strength and in general better properties at extreme temperatures, such as temperatures down to -30°C and up to +70°C.

Providing a skidproof deck can be achieved by providing the outer layer of the surface of the deck with special friction means. Such friction means can be provided during or after the pultrusion process itself and may, for example, include application of a layer of a suitable granulate or performing machining of the surface of the deck such that a certain roughness is produced.

A scaffold with a deck according to the invention can advantageously be provided with a fibre content of the plate member corresponding to a weight percentage between 40 and 80, for example between 50 and 75, such as between 60 and 70 by glass fibres, for example. By optimising the plastic used as matrix material in the product, an optimally high fibre content can be achieved in the finished product by which increased rigidity is achieved. For example, an optimised fibre content will be between 65 and 80%.

By using other types of fibres than glass fibres, e.g. types as indicated above or combinations thereof, various advantages are achieved. The weight can be optimised and at the same time the strength or load capacity is optimised. For example, fibres of glass can be used in some areas of a plate member while in other areas fibres with higher rigidity can be used, e.g. carbon fibres or steel fibres. In particular by pultruded items there is achieved optimal possibility for controlling and checking the position of respective fibres. Steel fibres, which in principle are thin strands of a suitable steel alloy, are particularly suited for the outermost surface of the top side of a deck for a scaffold as there is a very high wearability in such a surface, while e.g. carbon fibres are much better suited for being disposed in parts of the pultruded plate member in which tension is absorbed for the greater part, typically corresponding to the lowermost parts of a deck. Various types of fibres have different properties and applications why careful planning of the position of respective fibres can result in distinctive and optimal properties.

In a variant of a scaffold with a deck according to the invention, the plate member includes a top side and a bottom side, where between top side and bottom side a number of longitudinal stringers extend by which a spacing is maintained between top side and bottom side. Thus is provided a kind of sandwich construction wherein the spacing between top side and bottom side provides increased rigidity. The top side ensures disposition of the stringers and in principle absorbs compressive forces whereas the bottom side absorbs tensile forces together with the stringers, which can be regarded as beams partly absorbing compressive forces and partly tensile forces. The advantages of sandwich constructions are known from many different applications and with very many different materials and combinations of materials.

A particularly preferred variant of a scaffold with a deck according to the invention is that the plate member includes at least a partially open bottom side divided into a number of longitudinal faces, wherein the longitudinal faces are coherent with one or more of the longitudinal stringers. The bottom side may thus be constituted by a surface for each of the mentioned longitudinal stringers. The top side can e.g. be a plane and closed surface, where from the back side of the surface a number of stringers project and where each of these stringers in principle is similar to the web in a known I- beam. A deck thus includes a plurality of I-beams, the top of the I-beams being constituted by the top side of the plate member whereas the bottom side of the plate member is constituted by the lower flanges of the I-beams. However, it may also be envisaged that top side and bottom side both are closed and that a number of stringers or ribs extend between the two sides so that there is produced a closed profile with inner profile walls. Another possible variant is that the top side is closed while the bottom side is partly open as a surface at the bottom side is fixed to several of the mentioned longitudinal stringers or inner profile walls. Finally, the top side as well as the bottom side - irrespective of their general design - can be provided with apertures such that dust, mortar remains and other dirt can fall through such a plate member.

As mentioned above, the deck can include two end parts wherein the two end parts are selected among a number of differently designed end parts with specific properties. Such end parts for a scaffold with a deck according to the invention can be made of metal, fibre composite, plastic or combinations thereof, wherein the end parts are moulded and/or machined to the desired shape. The end parts include the said fixing means by which the deck is fixed to the scaffolding frames, and the fixing means may include hooks, cutouts in the bottom side or blocks mounted at the bottom side, or any other kind of fixing means known from scaffolding. In this way it is possible to perform a selection of end parts with a specific design according to the type of scaffold for which the deck is to be used. Furthermore, end parts with cutouts or with blocks intended to ensure that the deck/platform lies firm on a pipe as known from the so- called bricklayer's scaffolds can be selected.

In a particular preferred embodiment of a scaffold with a deck according to the invention, the end parts can be fixed to a plate member by gluing, welding or they can be fixed by mechanical securing. Such a mechanical securing can be effected, for example, by one or more pins, rivets, bolts or screws, or by one or more spring-biased locking pawls on the end parts, wherein the end parts interact with locking means adapted therefor on a plate member. An end part may advantageously be designed with one or more projecting fingers which are dimensioned to be passed into the end of the plate member, where fixing between end parts and plate part occurs by fixing between side faces of the plate part and/or stringers/inner profile walls and the projecting finger/fingers on an end part. The description of figures will show examples of mechanical fixing with a pin. Fixing may, as mentioned, also be effected by gluing or by another suitable process that renders separation of end part and plate member impossible at a later time.

By using a mechanical fixing there is achieved possibility of separating end part and plate member, either for shortening the plate member or for replacing an end part. Replacement may e.g. be effected because of wear or damage or because the deck is to be used for a different type of scaffolding. The end part is subsequently fixed to the plate member with the same or a different suitable method of joining.

In a preferred variant, an end part is provided with a spring-biased locking pawl which by joining with a plate member engages corresponding locking means adapted for the purpose. It may e.g. be a recess or other kind of cutout at either the top side, the bottom side or the longitudinal flanges between top side and bottom side of a plate member.

In yet a variant of a deck for a scaffold according to the invention, the end part may advantageously be arranged with its top side at level with the top side of the plate member and where the top side of the end part includes anti-skid means. The end part can hereby constitute part of the surface of the deck itself without risking fall accidents as the two parts are right at the same level, and thus with a surface preventing a user from skidding. Prior art solutions in the market describe several examples showing a difference in level at the transition between the deck itself and the end part, and typically also an edge, a surface or similar with a smooth surface. This problem is solved by the invention as the two parts are at the same level and as anti-skid means are provided at the top side of the end part in the form of a friction surface. This may e.g. be a coating applied after production, but in a preferred variant it is a rough surface established during or in connection with the making of the end part itself.

A deck for a scaffold according to the invention may furthermore include that the end parts are equipped with one or more sets of through-going apertures from the top side of the end part in direction towards the bottom side of the end part, for securing the deck to the scaffolding frames. These through-going apertures may advantageously be used for mounting a wire, steel wire, cable tie or similar by which a deck can be secured to a scaffolding frame such that it cannot be lifted, alternatively be entirely detached and removed by wind gusts. Such a through-going aperture will typically be with a diameter of 3, 4, 5 or 6 mm, but may be greater or lesser according to need. Furthermore, the apertures do not need to be circular which, however, appears to be most expedient.

By securing each single deck/end part in this way, - preferably at both ends and at either side of the end part - there is achieved increased certainty that a deck for a scaffold will not cause an accident in use due to faulty disposition and due to wind. Moreover, it is prevented that a deck can be blown off completely and down onto e.g. a pedestrian or a road user.

Another variant for a deck for a scaffold includes that at least one through-going hole is arranged in the end part for coupling to a hoisting rope or similar. By lifting in a through-going hole with a secure and closed hook or snap hook there is achieved optimal security that a deck is not released from the hoisting rope, causing injury on persons or material damage. Such a through-going aperture can advantageously be arranged in the outermost part of the end part which will be mentioned in the following with reference to the drawing.

In yet a variant of a scaffold with a deck according to the invention, the plate member can advantageously be provided with at least one marking for adaptation of the length of the plate member and, for example, with several sets of locking means for interacting engagement by one or more locking pawls on an end part. By having markings indicating various lengths of a plate member, either in centimetres or other linear measure, or alternatively indicating standard lengths for other types of scaffolding systems, there is achieved a significantly easier adaptation to various tasks.

A scaffold with a deck according to the invention may include a plate member where the plate member is built up with a top side and a bottom side, where between the sides there is provided a foamed plastic material, e.g. foamed PVC, polyurethane, or another plastic type suited for foaming. By such a design is also achieved a sandwich construction where a spacing is created and thereby rigidity in a plate member by separating top side and bottom side and simultaneously keeping these apart at a given distance. At the same time, this is a solution with the possibility of low self-weight which to a great extent is attributed to the foamed plastic material between the top side and the bottom side in the plate member. A plate member with a foam core can be provided with an end part in the same way as indicated above, and it will furthermore be possible to fill some or all the cavities present in a plate member with longitudinal flanges with a foam material as mentioned above.

As mentioned in the introduction, the invention also concerns a method for adapting a deck to a scaffold, wherein the length and/or end parts are adapted for a specific type of scaffold The method includes at least three of the following four steps:

- adapting the length of a plate member;

- choice of end part;

- mounting end part in the plate member;

- fixing end part in the plate member.

Description of the Drawing

The invention is described in the following with reference to the drawing, wherein: Figs. 1-7 shows a detail of a plate member and examples of fixing means on an end part for a deck for a scaffold;

Fig. 8 shows an example of a typical cross-section of a plate member;

Fig. 9 shows a deck/platform with fixing means at the bottom side;

Fig. 10 shows a detail of a deck with end part provided with skidproofing and at level with the top side of the deck;

Fig. 1 1 shows an end part with skidproofing.

In the explanation of the Figures, identical or corresponding elements will be provided with the same designations in different Figures. Therefore, an explanation of all details will not necessarily be given in connection with each single Figure/embodiment as well as all elements are not necessarily provided with designations in all Figures.

List of designations

1 detail of deck

2 plate member 3 top side

4 non-skid coating

5 bottom side

6 longitudinal side

7 transverse end on plate member

8 longitudinal stringer

9 cutout for pin

10 cylindrical pin

11 end part

12 fixing means

13 fingers on end part

14 transverse end on end part

15 edged pin

16 slots

17 blocks

18 skidproofing

19 top side on end part

20 rivet

21 through-going opening in end part

22 bottom side of end part

23 through-going opening in end part

24 hoisting eyelet

Detailed Description of Embodiments of the Invention

In Fig. 1 appears a detail of a deck in unassembled condition. The plate member 2 includes a top side 3 with a non-skid coating 4, a bottom side 5, two longitudinal sides 6 and two transverse ends 7 of which only one is seen. Between the top side 3 and the bottom side 5 are arranged a number of longitudinal stringers 8 which also can be termed inner profile walls. Transversely of the plate member 2 and in parallel with the transverse end is seen a through-going recess 9 adapted for receiving a cylindrical pin 10. Furthermore, in Fig. 1 is seen an end part 1 1 with fixing means 12 for joining or fixing to a not shown frame part on a not shown scaffold. The end part 11 further includes a number of fingers 13 which are adapted to be passed into the longitudinal spaces formed by the top side 3, the bottom side 5 and the longitudinal stringers 8. The end part 1 1 is also made with a transversal through-going cutout 9 for receiving a cylindrical pin 10. The shape of the cylindrical pin 10 may readily be changed, only requiring change of the cutout 9 in the plate member 2 and change of the end part 1 1 as well such that cutout 9 and pin 10 fit together. The pin 10 may, however, also be replaced by other suitable locking means, e.g. bolts, screws, rivets, spring-biased locking pawls, glue, welds or other mechanical or chemical methods of joining.

In principle, Fig. 2 shows the same as in Fig. 1, but with the difference that the fixing means 12 do not extend along the entire transverse end 14 on the end part 1 1. Furthermore, there is the difference that an edged pin 15 and an edged cutout 9 for receiving the edged pin 15 are shown.

Fig. 3 shows a variant with fixing means 12 that e.g. can be moulded in plastic or fibre composite as well as the end part 1 1. The fixing means can also be made of other types of material, including metal. The fixing means 12 can be mounted to the end part 11 after making, but may also be an integrated part of the end part 11. The same goes for the variants shown in Figs. 4, 5 and 6. In Fig. 7 is seen a variant of an end part 1 1 where the fixing means 12 are constituted by a transverse recess at the bottom side of the end part. Such a solution can e.g. be used on perforated platforms for a bricklayer's scaffold.

Fig. 8 shows a cross-section of a variant of a plate member 2.. The plate member 2 has a closed top side 3 and an open bottom side 5 where on each of the longitudinal stringers 8 there is arranged a narrow strip bottom side 5. The plate member 2 thus appears as a plurality of juxtaposed I-beams constituted by the stringers 8 and the top side and the narrow bottom side strips 5, respectively. The bottom side 5 is therefore open, appearing with a number of slots 16.

In Fig. 9 appears a deck 1 with a cross-section as also shown in Fig. 8, where at the bottom side 5 there are arranged fixing means in the form of blocks 17 having the purpose of securing the deck 1 on a scaffold. The blocks 17 can be glued or in other ways joined with the bottom side 5 or with the longitudinal stringers 8 between the top side 3 and the bottom side 5.

However, there may also be provided another type of end parts 1 1 which are pushed in between the longitudinal stringers 8 and project relative to the bottom side 5 in the mentioned slots 16.

These alternative end parts 1 1 do therefore not need to be at the ends 7 of the plate member 2 and may thus constitute the blocks 17 seen in Fig. 9. By such a solution it is possible to adjust the position of the blocks 17 to the actual needs. An alternative end part 1 1 can be fixed to the plate member 2 by various suitable means, they be permanent fixations by gluing or welding, or fixations which can be undone and reapplied again and again if so desired. There may e.g. be used pins 10, 14 as shown in Figures 1 to 7.

For the sake of good order it is to be mentioned that obviously the alternative end parts 1 1 do not need to include blocks 17 as shown in Fig. 9, but may also include fixing means 12 with other geometric shapes. In Fig. 10 appears a detail of a deck 1 where on the end part 1 1 is arranged a skidproofing 18, in this case established by providing the surface with a chattered pattern. Furthermore, it appears in Fig. 10 that the top side 3 on the plate member 2 is at level with the top side 19 of the end part. At the top side 3 of the plate member 2 and at the sides thereof appear rivets 20 used for fixing the end part 1 1 to the plate member 2. Transversely through the end part 11 at either side are arranged two through-going apertures 21 extending from the top side 19 to the bottom side 22 on the end part 1 1. Furthermore, two hoisting eyelets 24 are seen in the end part 1 1.

Fig. 1 1 shows part of an end part 1 1 with skidproofing 18 and with through-going apertures 21 and hoisting eyelets 24.

Claims

CLAIM S

1. A deck for a scaffold wherein the scaffold includes scaffolding frames as well as decks, wherein the scaffolding frames are typically made of steel and wherein the deck is made with fixing means for fixing a deck to the frames, wherein the fixing means at least include cutouts and/or projections, wherein at least part of the deck is made of a fibre composite material and includes at least one plate member with a top side, a bottom side, two longitudinal sides and two transverse ends, characterised in that a deck further includes two end parts, each with a top side and a bottom side, wherein the fixing means are arranged on or in the end parts, and that the plate member is entirely or partially made by pultrusion, with a weight of between 8 and 14 kg/m² or less, alternatively with a weight between 9 and 1 1 kg/m².

2. A deck for a scaffold according to claim 1, characterised in that the plate member is made of fibre composite, wherein the fibres are selected among glass fibres, carbon fibres, aramide fibres, polyethylene fibres, steel fibres, other plastic fibres or natural fibres, such as plant fibres, or any combination of the mentioned fibre types, and wherein the fibres are embedded in a matrix of a suited type of plastic, e.g. polypropylene, polyester, vinyl ester, epoxy, polyurethane, or other suited type of plastic.

3. Deck for a scaffold according to any of claims 1 and 2, characterised in that the fibre contents of the plate member constitute a weight percentage between 40 and 80, for example between 50 and 75, such as between 60 and 70 by e.g. glass fibres.

4. Deck for a scaffold according to any of claims 1 to 3, characterised in that the plate member includes a top side and a bottom side, where between top side and bottom side a number of longitudinal stringers extend by which a spacing is maintained between top side and bottom side.

5. A deck for a scaffold according to claim 4, characterised in that the plate member includes at least a partially open bottom side divided into a number of longitudinal faces, wherein the longitudinal faces are coherent with one or more of the longitudinal stringers.

6 Deck for a scaffold according to any of claims 1 to 5, characterised in that the deck includes two end parts wherein the end parts are selected among a number of differently designed end parts with specific properties.

7. Deck for a scaffold according to any of claims 1 to 6, characterised in that the end parts are made of metal, fibre composite, plastic or combinations thereof, wherein the end parts are moulded and/or machined to the desired shape.

8. Deck for a scaffold according to any of claims 1 to 7, characterised in that the end parts are fixed to a plate member by gluing, welding or is fixed by mechanical securing, the mechanical securing being effected, for example, by one or more pins, rivets, bolts or screws, or by one or more spring-biased locking pawls on the end parts, wherein the end parts interact with locking means adapted therefor on a plate member.

9. Deck for a scaffold according to any of claims 1 to 8, characterised in that the end part is arranged with its top side on a level with the top side of the plate member, and that the top side of the end part includes anti-skid means.

10. Deck for a scaffold according to any of claims 1 to 9, characterised in that the end part includes one or more sets of through-going apertures from the top side of the end part in direction towards the bottom side of the end part for securing the deck to the scaffolding frames.

11. Deck for a scaffold according to any of claims 1 to 10, characterised in that the plate member is provided with at least one marking for adaptation of the length of the plate member and, for example, with several sets of locking means for interacting engagement by one or more locking pawls on an end part.

12. A method for adapting a deck to a scaffold according to any of claims 1 to 1 1, wherein the length and/or end parts are adapted for a specific type of scaffold, characterised in that the method includes at least three of the following four steps:

- adapting the length of a plate member;

- choosing an end part;

- mounting end part in the plate member;

- fixing end part in the plate member.