WO2001012914A1 - Building construction with retractable roof panel - Google Patents

Abstract

In a building construction, particularly a dome-shaped construction for a sports stadium, the roof includes at least one sloping section which has a three-dimensional faceted- or dome-shaped panel (5) arranged to retract by sliding down the roof.

Description

  
 



   BUILDING CONSTRUCTION WITH   RETRACTABLE    ROOF PANEL
 The present invention relates to a building construction having one or more retractable roof panels and relates particularly, but not solely, to a dome-shape building construction which may be used as a sports stadium.



   A number of major stadia have been built, in various parts of the world, with sliding or retractable roofs, often to provide venues capable of staging international events or championships. There are self-evident attractions in being able to retract the roof of a sports or leisure facility in fine weather but still have the certainly of being able to hold the event should inclement weather prevail: this is particularly so in northern Europe, where the weather conditions are uncertain.



   A retractable roof can also form part of the temperature control system, either during the day or at night, for a large, enclosed space. In hot weather at night, cooling is possible by opening the roof for a predetermined period.



  In situations where the building is generating surplus heat, say from a large crowd, immediate cooling or ventilation can be achieved by retracting at least part of the roof.



   Previous proposals have incorporated one sliding roof panel which passes over another sliding roof panel: in some such proposals, an upper sliding panel is carried, in some phases of movement, by a moving panel below. A considerable number of proposals involve an arch-shaped roof section moving over a similar moving section. Many proposals seek to achieve a completely open area over the pitch or track, but the construction is necessarily very costly. A significant disadvantage of multiple-layered moving panels is that this arrangement severely limits the construction depth that can be utilised for all the moving panels below the uppermost one.



   In enclosed spaces, containing large numbers of people,  it is a fundamental requirement to ensure safety in the event of a fire. Because many fatalities in a fire are caused by smoke, it is vital to provide for the release or removal of smoke under fire conditions. Buildings may be designed so that the roof cladding will burn through to release smoke.



  Alternatively, extraction fans may be provided. A fundamental flaw in any system which requires electrical power is that the fire may destroy or interrupt the power supply:   back up    systems may be provided, but concerns will remain as to whether these will work when required to do so.



   In accordance with the present invention, there is provided a building construction the roof of which includes at least one sloping section, the sloping section including a three-dimensional, faceted or dome-shape panel arranged to retract by sliding down the roof.



   The three-dimensional form of the retractable panel gives structural strength to it and enables the panel to be lighter in weight than a flat panel reinforced to give equivalent structural strength.



   The three-dimensional panel may be faceted in the form of a pyramid or otherwise, or may be dome-shaped.



   The arrangement provides the ability to open the roof panel easily, and involves much lower cost than previous proposals and is able to give a higher standard of weathertightness.



   The sloping section will generally include a lower panel which is stationary, and over which the retractable panel slides, this lower panel having a generally planar upper surface.



   Preferably the retractable panel is generally triangular in plan and may be made up of three triangular subpanels, for example forming a frame in the shape of a pyramid.



  Alternatively, the panel may be of generally uniform depth over  its area, with generally vertical sides.



   Preferably the roof comprises a number of sloping sections, which incline downwardly in different radial directions from a common top point or apex, the retracting panels of the respective roof sections meeting at the top.



  Each retracting panel preferably has three support points, at or adjacent its respective corners, for example in the form of running wheels or sliding formations. Preferably each retracting panel can be moved independently of the others: preferably each panel can be moved to and stopped at any desired position along its path of travel.



   Preferably the building construction is generally in the shape of a dome, with a number of sloping roof sections (e. g. 6 sections) inclined in respective radial directions which are spaced-apart (preferably equally) around   360 .   



   Preferably the building construction comprises a skeleton or framework which supports the roof panels, respective beams of the framework providing tracks along which the wheels or other support points of each retractable panel move.



   Each retractable panel may be assembled on site from prefabricated components: preferably the assembly is completed at ground level then the panel is lifted into position on the roof, although it may instead be assembled on the roof. The panel may comprise a framework, e. g. in three parts fabricated from tubular metal members welded together, the framework then being clad (either at ground level or on the roof): this form of construction provides structural rigidity during movement and is of minimal weight. The cladding of the retractable panel may be transparent (e. g. glass) or non-transparent (e. g. corrugated metal sheeting). The cladding may be insulated and/or the cladding may incorporate sound baffling to improve acoustics.  



   The apices of the triangular-plan retractable roof panels may be rounded or truncated. The upper surface of the panel may be curved. Because, in each sloping section of the roof, there is only a single moving panel, there is no significant constraint on its possible depth: it can therefore be designed to span any required opening by increasing its depth to ensure the required structural strength. Typically, the panel may have a depth of one tenth to one twentieth of its span. Thus, the shape of the panel enables it to have a substantial span-to-depth ratio, whilst avoiding the cumbersome and unattractive appearance, when seen in elevation, of a rectangular, non-tapered shape. The panel may span one quarter of the diameter of the stadium.



   The retractable panel may be susceptible to wind uplift, because of its relatively light weight. In order to resist this, at least the upper support point of the panel may include a hooked bracket to engage under a rail on the support beam, or a running wheel engaged under the support beam. The retractable panel may in addition, or instead, include a vent to reduce the uplift forces.



   The support points of each retractable panel may comprise running wheels which are smooth, lipped or toothed.



  At least one of the support wheels may be driven.



  Alternatively, a drive wheel may be provided in addition to the three running wheels.



   The drive system for each retractable panel may comprise a rack and pinion system, a chain drive, cable drive or hydraulic cylinder. The power may be electrical or hydraulic.



   The mating edges of the adjacent retractable panels are preferably provided with seals to give weathertightness when closed. The seals may comprise replaceable brush seals, and/or elastomeric seals.  



   Preferably each retractable panel is arranged so that, in the event of power to the building being lost, it will open partially under gravity, enabling the release of smoke.



   Preferably an emergency/parking brake is provided to limit movement of the retractable panel down the roof due to failure of the drive system.



   Preferably a crash barrier is provided to arrest the retractable panel should it slide uncontrollably down the roof.



   An embodiment of the present invention will now be described by way of example only and with reference to the accompanying drawings, in which:
 FIGURE 1 is a perspective view of a dome-shaped building construction in accordance with the present invention, shown with its retractable roof panels closed;
 FIGURE 2 is a similar view of the construction of
Figure 1, shown with its retractable roof panels fully open;
 FIGURE 3 is a view showing the formation of one of the retractable roof panels from three flat trusses;
 FIGURE 4 is an enlarged view of one of the retractable roof panels installed on the dome construction;
 FIGURE 5 is an enlarged view of a portion of the framework of the dome construction;
 FIGURE 6 is a view of a portion of the dome framework, showing the plates on which the wheels of a retractable roof panel run;

  
 FIGURE 7 is an enlarged section view showing one of the running wheels of a retractable panel engaged with its support beam ;
 FIGURE 8 is a sectional view showing the drive motor of a retractable panel and its engagement with the running rack; and
 FIGURES 9 and 10 are views of an emergency/parking brake of each roof panel, in engaged and disengaged positions,  respectively.



   Referring to Figures 1 and 2 of the drawings, there is shown a generally dome-shaped building construction, which may be used as a sports stadium, having a number of roof panels 5 which retractable in respective radial directions. In the example shown, the construction has 6 identical roof sections which incline radially outwardly in equi-angularly spaced directions. Each retractable roof panel 5 is assembled on-site from three pre-fabricated trusses 1,2,3 (Figure 3), to form a spaceframe which is then clad. It will be noted that the trusses 1,2,3 are flat and triangular in shape, whilst the assembled panel 5 is in the shape of a pyramid. Each retractable panel 5 has free running wheels 6 (Figure 4) at its three corners which run on respective beams of the roof framework, as will be described below.



   The construction comprises a generally dome-shaped framework which includes a number of split-leg beams 16 connected at the apex by a ring or doughnut 17 (Figure 5).



  Thus, each split-leg beam 16 has an upper section 16a which extends radially outwards from the apex, then two diverging lower sections 16b, arranged so that respective lower sections 16b of adjacent split-leg beams extend parallel to each other (Figure 4).



   Circumferential strutting is provided by beams 18 extending between adjacent split-leg beams 16, at the outer ends of their upper sections 16a. A support beam 10, for the upper wheel of the respective retractable roof panel 5, extends radially from the doughnut 17 to the beam 18, mid-way between each pair of upper leg sections 16a. Fixed, flat panels are provided over the outer areas of the roof, i. e. between the lower leg sections 16b, outwardly of the circumferential beams 18.



   The wheels 6 of each retractable roof panel 5 run on  metal plates 12 mounted to the lower leg sections 16b and to the beam 10: these metal plates are levelled up after the structure has taken up its dead load deflected shape. Each wheel 6 is of solid rubber and runs between a pair of guide rails 22 (Figure 7): each wheel is mounted to its panel 5 by means of a suspension mechanism and at least the wheel at the top corner of the panel incorporates a brake, the suspension mechanism and brake being indicated diagrammatically at 19 and 24, respectively, in Figure 7. Wind uplift on the panel 5 is resisted by hooked metal straps 25 carried by the wheel mounts and engaging under hook-section rails 26 secured to the sides of the support beam   10:    wind uplift is accordingly transferred from the panel 5 to the main structure.



   Referring to Figure 8, a drive motor 7 is mounted to the underside of each retractable panel 5 via a constant force system 23, comprising hydraulic cylinders, which ensures that the toothed drive cog 8 maintains engagement with a toothed rack 9 which extends along the support beam 10.



   An emergency/parking brake 11 is provided (Figures 9 and 10) and arranged to turn about its pivot 15 under gravity, for its lower end to engage the rack 9, when the power to drive the motor is off. A fractional movement of the panel 5 up the slope under power releases the brake 11, which remains latched in its disengaged position (Figure 10) whilst power is on. The brake 24 is applied automatically when the power is off.



   The retractable panel is, however, arranged to open partially under gravity, in the event of a loss of power to the building. For this purpose, the brake 11 may be arranged to be ineffective over an upper portion of the panel's movement, say the upper 2 metres, and the brake 24 ineffective in the event of loss of power to the building.



   Referring to Figure 4, dampers 13 are provided to absorb the energy of the moving panel 5 at the top and bottom  of its travel. Further, emergency crash barriers 14 are provided near the bottom travel position to restrain the panel should it slide down the roof, out of control.
  

Claims

CLAIMS 1) A building construction the roof of which includes at least one sloping section, the sloping section including a three-dimensional, faceted-or dome-shape panel arranged to retract by sliding down the roof.

2) A building construction as claimed in claim 1, in which said retractable panel is generally triangular in plan and is supported at each of its three corners.

3) A building construction as claimed in claim 1 or 2, in which said roof comprises a plurality of said sloping sections, the respective sloping sections being inclined downwardly in different radial directions from a common top point, the retracting panels of the respective sections meeting at said common top point when closed.

4) A building construction as claimed in claim 3, in which said roof is generally in the shape of a dome with the radial directions in which the respective sloping sections are inclined being spaced-apart around 360 .

5) A building construction as claimed in any preceding claim, in which said roof comprises a framework which supports said retractable roof panels, respective beams of the framework providing tracks along which the support points of the respective panels move.

6) A building construction as claimed in claim 5, in which, for the or each said retractable panel, said framework comprises a first beam which extends radially outwardly, for a support point at the upper corner of the panel, and second and third beams which extend parallel to each other, for support points at the other two corners of the panel.

7) A building construction as claimed in any preceding claim, in which the or each retractable panel is arranged to open partially under gravity in the event of a loss of power to the building.