The present invention relates to scaffolding for supporting platforms, walkways, and formwork, and in particular the present invention relates to scaffolding for the building and construction industry.
Traditionally scaffolding systems are used during the construction and/or maintenance of large structures, for example buildings, silos, ships, monuments and dams etc. Scaffolding is erected generally on the outside of such structures, however, internal use is not uncommon. The scaffolding, once erected, provides practical access to areas of the structure that would otherwise be difficult, if not impossible to reach. Generally, such areas are at a height beyond the reach of practical ladder and platform access. Such systems allow tradespeople to work at heights above a ground or base construction level safely and effectively, and also allow the safe storage and placement of trades materials. The traditional systems are commonly erected from the ground upwards, whereby upright poles are supported on the ground and interconnected via a network of cross-members and/or platforms to give stability and rigidity to the framework arrangement. As the lower levels of a structure are completed or as maintenance work moves upwards, it is commonly necessary to extend the scaffolding accordingly. This often requires connecting further uprights to the original ground supported uprights, with further interconnecting cross-members etc to add stability. As the system gains height it may be necessary to tie or fix the scaffolding into the structure for further safety and stability. Once assembled, the traditional form of scaffolding is fixed to the structure and cannot be moved without substantial, if not total disassembly. Thus, as work on the structure extends continues upwards, the lower levels of the scaffolding can become redundant, wasting materials that are not in use and requiring further materials to be brought in to continue extending the scaffolding and thus work at higher levels.
Solutions to these problems have been previously proposed by so-called ‘second generation’ systems. One system known in the art is a detachable ‘jump’ or ‘hanging’ scaffolding system. In such a system the scaffolding is erected to a limited height extent and anchored in situ to the structure. As work proceeds upwards to higher construction or maintenance levels, the scaffolding can be detached from the structure and hoisted one unit at a time by crane to the required new height. Each scaffolding unit is then reset and re-attached to the structure at the new height. However, such systems are only able to accommodate scaffolding units of an area approximately 3 to 4 metres square due to the limiting practicalities in lifting and moving large sections of unitary scaffolding by crane. Commonly, by their very nature, such systems are employed in urban or built up areas having limited clearance or safety zones. Also, any lifting, moving and refixing operations necessarily need to take into account the prevailing weather conditions up until the scaffolding is safely refixed. During poor weather conditions, for example high winds or limited visibility it is impractical and unsafe to have a large scaffolding unit suspended in free space from a crane. Re-attachment would also prove difficult and may be considered dangerous in such circumstances. Due to the aforementioned impracticalities in moving sections of such a system, the units need to be smaller than would otherwise be desirable, therefore requiring a larger number of the units, and correspondingly a greater number of crane movements or additional cranes to move them. A high number of scaffolding units, along with the associated problems in moving such units has implications of increased construction time and costs along with an additional safety risk associated with moving the units in free space by crane.
An alternative system proposed is the automated or ‘self-climbing’ system. Such systems are commonly a self-climbing assembly used primarily as a vertical wall formwork for forming concrete surfaces. U.S. Pat. No. 5,000,287 issued to Schwörer discloses such a system of “self climbing” formwork for erecting a concrete wall. The system includes a scaffolding platform that is moved by hydraulic linear drives along upright carrier rails mounted to a section of the wall, one linear drive per rail. Once the platform is driven to the top of its respective rails, it is maintained in that position whilst the rails are subsequently moved upwardly and fixed to the next section of wall. Thus, to advance the platform upwards the system requires a relatively complex two step process of alternately moving the platform, then the rails, then the platform etc.
U.S. Pat. No. 4,060,358 issued to Fougea is a further known system of self climbing formwork. This system discloses the use of hydraulic actuators to advance and position a formwork frame along a wall under construction. The frame is provided with multiple hydraulic actuators, each attached at one end thereof to move the frame along the wall, the other end of each actuator being adapted to hook onto brackets mounted to the wall. During movement of the frame, cams in the form of ramps engage with the brackets to maintain the frame in a required position. Sliding bearing arms are then needed to be placed in position to support the frame and thereafter need to be removed to permit the frame to be advanced upwardly relative to the wall.
Thus, unlike the previously described systems, self climb systems, which are required to make relatively small, incremental movements along a wall under construction to enable accurate positioning of the formwork, are not moved by crane, rather they are shifted automatically by in-built hydraulic jacks or rams. Although such systems avoid the aforementioned problems associated with hoisting units in free space by crane, they are comparatively expensive and also complex and difficult to install. Commonly, such systems require multiple hydraulic actuators which also need to be synchronised in order to maintain consistent, unhindered movement of the frame without jamming on the rails.
It that would therefore be advantageous to provide a scaffolding system that reduces the aformentioned problems and limitations associated with the prior art systems.
It would further be advantageous to provide a method for positioning a scaffolding system that reduces the aformentioned problems associated with the prior art systems.
Thus it would be advantageous to provide a simplified scaffolding system wherein a scaffolding assembly is simultaneously guided during raising and/or lowering and removably retained to a structure, and also supported following repositioning.
Therefore in one aspect the present invention provides a scaffolding system including;
Thus, the present invention advantageously provides a scaffolding system that reduces the problems of positioning and fixing movable scaffolding assemblies associated with the aforementioned prior art systems.
Preferably the moving means attaches proximate the upper end of the scaffold assembly via the tie element.
In a further aspect of the present invention there is provided a scaffolding system including;
Thus advantageously the present invention provides a scaffolding system that reduces the problems of positioning and fixing movable scaffolding assemblies associated with the aforementioned prior art systems.
In a still further aspect of the present invention there is provided a scaffolding system including;
Thus advantageously the present invention provides a scaffolding system that reduces the problems of positioning and fixing movable scaffolding assemblies associated with the aforementioned prior art systems.
Preferably each elongate member is a beam or rail of regular cross section, for example U, I, H, square, or round etc. thus facilitating smooth positioning of the assembly.
Preferably, the guide means are integral of the brackets. More preferably the guide means and retaining means of each bracket are also integrated. Thereby reducing the number of components required, and thus saving materials and production, assembly costs. Also, the construction of the brackets is simplified.
More preferably, the integrated guide and retaining means are provided as one or more pairs of pivotable arms arranged to pivot to a locked position for retaining each elongate member and an unlocked position for releasing said elongate member, thus providing a simple yet effective clamping arrangement.
Preferably the supporting means includes an arm pivotably attached to the bracket and a stop means, such that the arm may pivot to allow passage of a support portion during raising of the assembly, but prevent return of the support portion by interaction of the stop means with a portion of the bracket. Thus the supporting means advantageously provides a convenient ‘one way’ valve or ratchet type arrangement.
Still more preferably, the support portion of each elongate member may be provided by one or more pins, bolts, or combinations thereof, which can be arranged to pass through and be retained in apertures formed in each elongate member. However, more preferably such pins, bolts, bars or combinations thereof may be removable or permanently fixed, thus providing simple yet effective support for the assembly.
Preferably, the brackets are constructed for mounting to a structure by one or more bolts, adhesives, anchor means, or combinations thereof, for example by through slab, through beam or embedded beam/slab anchoring, thus providing convenient and practical means for mounting to a structure, and thereby retaining the assembly.
Preferably, the system includes a means for raising and/or lowering the assembly, for example, a crane, hydraulic or electrically driven actuators, which may be jacks or rams etc.
More preferably, the system may further include formwork means, for example, bracket and panel assemblies for mounting to the system such that concrete or other related construction materials can be utilised to form walls or other constructional arrangements in situ. Thus the system of the present invention is advantageously adaptable to also permit formwork to be constructed.
Preferably the scaffolding assembly is modular and can be preassembled before being attached to any of the brackets. Preferably the scaffolding assembly extends to cover an area 10 metres wide by 12 metres high. More preferably 5 metres wide by 12 metres high. Thus significantly large areas of a structure or construction can be covered with any one assembly.
Preferably the upright elongate members of the scaffolding assembly include connected U section beams, preferably connected ‘back to back’, and the scaffolding assembly further includes cross-members interconnecting said beams to form a framework.
Preferably the scaffolding assembly further includes one or more platform members for supporting persons and/or materials. Thus the scaffolding assembly advantageously provides a safe working/storage position supported on the brackets.
It is a further object of the present invention to provide a method of positioning a scaffolding assembly having an upper and lower end, including a plurality of elongate members, said members including support portions, wherein said method includes the steps of:
Thus the present invention advantageously provides a method which permits positioning of a scaffolding assembly that alleviates the aforenoted problems associated with the prior art, for example, due to poor weather conditions e.g. strong winds.
Preferably step a) includes attaching the moving means proximate the upper end of the scaffold assembly.
Preferably, the method further includes the step of releasably mounting the scaffolding assembly to brackets provided on a structure prior to method step (a), thus allowing flexibility during erection of the system and therefore movement of the assembly.
More preferably the method further includes the step of pre-assembling the scaffolding assembly prior to mounting to the structure such that the present invention envisages the positioning of modular or unitary scaffolding systems.
Still more preferably, during positioning of the assembly, the support portions are arranged to act on the support means to move the support means out of their path, and said support means return under the force of gravity to block
Preferably said positioning step, step e) includes receiving each support portion in a receiving bracket of each corresponding support means.
a shows a first bracket according to one embodiment of the present invention mounted to a lower level of a building under construction. The scaffolding assembly, in this embodiment, is yet to assembled in unitary form and retained by the bracket.
b shows a side view of the scaffolding system according to one embodiment of the present invention retained by the bracket of
c shows a side view of the scaffolding system as shown in
d shows another side view of the scaffolding system as shown in
a to 2f show the sequence of moving and repositioning the scaffolding assembly relative to one of the brackets according to an embodiment of the present invention.
a shows a bracket according to one embodiment of the present invention with retaining means for retaining a portion of the scaffold assembly.
b shows the bracket of
The scaffolding system according to a particular embodiment of the present invention will hereinafter be described with reference to the drawings.
The phrase ‘scaffolding assembly’ refers to the arrangement of upright elongate rail members that are interconnected by cross-members, platforms and/or formwork etc forming a framework for mounting to a structure. A side view of one form of the assembly is shown in
a shows a first bracket 3 of the scaffolding system 1 of the present invention mounted to a lower level 4 of a building under construction. The bracket is shown in a through beam anchoring arrangement, though through slab and embedded beam/slab anchoring arrangements are also envisaged.
c shows a second, higher level bracket 3 mounted to the building at the second higher level 6 of construction. The assembly 2 is shown here also retained by the bracket 3 at the second level 6. The third and highest level 10 depicted in the drawings is shown under construction. This is the level to which the topmost platform 8 needs to be raised to in order for the scaffold assembly 2 to be useful without requiring extension.
The assembly is shown in
a to 2f show the sequence of operation of one embodiment of the brackets 3 and assembly support means. The bracket 3 is shown in each view 2a to 2f mounted to a level of the structure. Mounting is in this instance is by the through-beam anchor arrangement 24. The bracket 3 includes a support means in the form of a pivotably mounted arm 25. The arm 25 is shown pivotably connected at an inboard end thereof to the bracket 23. The outboard end is adapted to include a bracket for engagement with a support pin of the elongate member 22. The arm also includes a stop means (not shown) for engagement with the body of the bracket 23 when in a horizontal position. The stop means prevents the outboard end of the arm from pivoting below the horizontal position. It will be appreciated however, that although in this instance the arm is not intended to pivot below horizontal, other arrangements and configurations of the bracket 23 may include support means for the elongate member 22 which may do so depending on the particular arrangement required. The outboard end of the arm 25 is arranged to support a rail pin 27a inserted through an aperture 26 of the elongate member 22, thereby the elongate member 22 is supported by the bracket via the arm and pin 27a. Should one pin 27a fail, one or more additional pins 27b may be positioned above the first so as to provide saving support for the elongate member 22.
With reference to
The sequence of moving and repositioning the scaffold assembly 2 will now be described with reference to
a shows a bracket of one embodiment of the present invention with an arm supporting means interposed between one pair of pivotably mounted opposed cooperating jaws 32a, 32b.
b shows one particular embodiment of the bracket 23 for retaining a portion of the scaffolding assembly of the system of the present invention. The bracket 35 shown is arranged for mounting to a structure via a backplate 36. The bracket includes two pairs of cooperating pivotable arms 32a, 32b and 33a (not shown), 33b. The uppermost set of arms 32a, 32b are shown in an open, unlocked position, whilst the lowermost set 33a, 33b are shown in a closed, retaining position. Each pivotable arm includes a slot for engagement with a flange portion of a longitudinally upright elongate member 31 of the scaffolding assembly. The elongate member 31 shown includes a pair of U shaped beams joined in a spaced relationship by joining plates 35. However, it is envisaged that beams of various other sections may be used, for example H or I beams. The supporting means 39, for example, the arm 25 of
During mounting of the assembly to a structure, the pairs of pivotable arms 32a, 32b and 33a, 33b are opened to allow the elongate member to be positioned relative to the bracket 30 with the arm (25,
While particular embodiments of the present invention have been herein described, it would be obvious to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention.
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/SG02/00078 | 5/6/2002 | WO | 11/5/2004 |