Field of the invention [0001] The present invention relates to a building structure, such as a stadium, in particular for playing sports, comprising an isolating airdome fixedly attached to the ground, and a covering structure for covering at least a part of the airdome.

Background of the invention

[0002] Such a building structure is known from for example the international patent publication WO 2012/073061 Al . This patent publication describes a stadium having a fixed dome and a rotatable dome that can be turned around a vertical axis of rotation around the fixed dome to provide the fixed dome with on-demand protection against precipitation, excessive sunshine, et cetera.

[0003] In DE2141953, a building structure comprising an inflatable cover having a middle transparent roof area is shown. The building structure also comprises two apses which obstruct light. The transparent roof area can be (partially) covered by a cover which can either absorb or reflect sunlight. The cover can be enlarged by means of attachment-pieces along the lengthwise edges. A gusset-shaped edge-piece is at the front-part of the cover. Along the lengthwise edges holes are provided for tension cables, with strips on the inside to prevent the cables from damaging the cover. The centre line of the cover is positioned over the ridge line.

[0004] GB2318369 discloses a cover structure for covering a vehicle having a base cover sheet and an inner cover sheet defining a storage chamber. The base and inner cover sheets are joined together around the peripheral edges. The cover structure comprises an opening to allocate a fan assembly to drive air from the external ambient into the storage chamber to inflate the structure. The space between the base and inner cover sheets may be also inflated with the fan assembly. [0005] A disadvantage of the known building structures, is that the building structures are is not capable of providing sufficient protection against extreme heat, sand storms, et cetera, and in particular a combination thereof. [0006] Furthermore, it takes a relatively long time to build the building structure. Additionally, the building structure is relatively inflexible, when, for example, a user wants to use the building structure for other purposes.

[0007] It is therefore an object of the present invention to provide a building structure that provides sufficient protection against extreme heat, sand storms, et cetera, and in particular a combination thereof.

[0008] It is a further object of the invention to provide a building structure that can be built relatively quickly and that offers a flexible construction.

Summary of the invention

[0009] Hereto the building structure according to the invention is characterized in that the covering structure comprises a tent structure arranged over substantially the whole of the airdome, when seen in top view, wherein the tent structure has a top and a circumference, the top being provided with an opening and being located at a greater height than the circumference of the tent structure, the circumference being placed at a vertical distance from the ground, the tent structure comprising a fabric and having a generally convex shape with respect to the airdome, wherein a convex side of the tent structure is turned towards the airdome, wherein the convex side of the tent structure and an outer surface of the airdome are spaced-apart at a distance.

[0010] By providing such a tent structure, the airdome can be shielded from excessive sunshine, wind and precipitation. Furthermore, the inventors have found that the tent structure and the outside of the airdome have to be spaced-apart to generate enough heat flow towards the opening in the top to cool the outside of the airdome, while at the same time the airdome is prevented from being covered by sand, especially during a sand storm, wherein the sand can be blown in from the side from under the circumference of the tent structure.

[0011] The tent structure may cover an area of for example as large as 20000-40000 m ² , for instance approximately 30000 m ² , i.e. enough to accommodate two adjacent, rectangular soccer playing fields.

[0012] The top of the tent structure can be embodied as a wind tower. Alternatively, a nebulisation device can be arranged near the top, depending on local air temperature and humidity.

[0013] An embodiment relates to a building structure, wherein, at an intermediate position between the top and the circumference of the convex side of the tent structure and an outer surface of the airdome, the convex side of the tent structure and an outer surface of the airdome are spaced-apart by a distance of at least 0, 1 m, more preferably at least 0,2 m, even more preferably at least 1,5 m, most preferably at least 2 m. The inventors have found this minimum distance is preferred to create the required amount of updraft. Depending on circumstances, in particular depending on the desired updraft, a smaller distance of for instance approximately 0,01 m, 0,02 m, 0,05 m, or distances in the range of 0,05 - 0,1 m are also conceivable.

[0014] An embodiment relates to a building structure, wherein the vertical distance between the circumference and the ground is at most 10 m, preferably at most 5 m, more preferably at most 2 m. This further prevents sand from being blown in, while at the same time providing enough draft towards the opening in the top to dissipate heat.

[0015] An embodiment relates to a building structure, wherein the ground below the airdome is provided with an underground piping system, through which coolant is circulated, during use, for absorbing heat from the airdome. This provides an even higher degree of cooling of the airdome, especially in very hot climates, such as desert climates. [0016] A further embodiment relates to a building structure, wherein the tent structure is supported near the top by a supporting pole, wherein the supporting pole extends downwards, from the top, through an opening in the airdome to a ground position within the airdome. Therein, the airdome may resemble a torus-like shape, or a section/part thereof. The supporting pole provides for a relatively simple supporting mechanism for the tent structure. The supporting pole, when seen in top view, as well as the opening, may be placed at a distance from the geometrical centre of the tent structure/airdome. [0017] In another embodiment, the tent structure comprises a plurality of tops with a corresponding plurality of openings, wherein a similarly corresponding plurality of supporting poles extend from the plurality of tops to a ground position within the airdome. This allows for a more stable supporting mechanism for the tent structure, especially in climates or areas with a lot of wind or high wind speeds.

[0018] Yet another embodiment relates to a building structure, wherein the plurality of supporting poles converge at a single ground position within the airdome. This allows relatively optimal use of ground space within the airdome, allowing the airdome to be optimally useable for its primary function, such as serving as a sports facility.

[0019] Preferably, the plurality of supporting poles comprises two or three, preferably at least three, supporting poles. The inventor has found that this number of poles provides good structural stability to the tent structure. The one or more supporting poles can be as high as 40-80 m, such as approximately 60 m. Furthermore, the one or more supporting poles preferably comprise a truss structure. The thickness of the poles can be around 4 m, depending of course on the tent structure weight to be carried.

[0020] In an embodiment, the fabric of the tent structure comprises a layer capable of converting solar energy into electricity. Since the building structure is especially useable in climates or regions with a lot of sunshine, it is beneficial to provide fabric of the tent structure with means for generating electricity from sunshine, for instance for powering devices inside the building structure, such as further cooling systems, for instance air conditions systems. [0021] Furthermore, the above provides a building structure that produces its own energy. Optimally, it does not consume more energy than it produces as to obtain an 'energy neutral' or 'climate neutral' building structure.

[0022] Preferably, the fabric of the tent structure comprises a heat reflective membrane layer to shield the airdome from excessive irradiation of sunshine.

[0023] Additionally, the fabric of the tent structure may comprise a layer incorporating a solar warm water collecting system. Such a system may also be attached to the tent structure.

[0024] Furthermore, the fabric of the tent structure may comprise a layer transparent to daylight or a layer of translucent materials for daylight penetration. By allowing light frequencies corresponding to daylight to pass through the tent structure, the perception of light within the airdome is found to be more natural, contributing to a feeling of well-being of persons present therein. Of course, it is required that the airdome itself also is at least transparent to daylight. [0025] Optimally, the fabric of the airdome as well as the fabric of the tent structure are configured for allowing a light intensity of 60-600 lux to be achieved within the airdome. For sports, a light intensity relatively close to 600 lux is desirable, whereas, when the airdome is used for instance as a museum, a light intensity relatively close to 60 lux is sufficient.

[0026] Preferably, the fabric of the tent structure is supported by a cable structure to provide especially relatively large tent structures with enough structural strength.

[0027] A further embodiment relates to a building structure, wherein, when seen in top view, the cable structure comprises a plurality of radial cables running in a radial direction from the top towards the circumference of the tent structure, wherein, near the circumference, the cable ends are each attached to a connecting member installed in the ground. In this way, a cable support structure capable of supporting a relatively large weight (i.e. per m ² of fabric surface area) can be realized. Therein, the sagging of the fabric can be adjusted by adapting the tension of the radial cables. The connecting members can be as high as 5-6 m. [0028] An embodiment relates to a building structure, wherein, when seen in top view, adjacent radial cables are spaced-apart at an angle of 10-15°, preferably approximately 12°. In this way, a relatively optimal spacing between adjacent radial cables is achieves, i.e. capable of supporting a considerable fabric load, while keeping the combined structural weight of the radial cables relatively low. The amount of radial cables can thus e.g. range from approximately 20-40, for instance 30, cables. An appropriate radial cable diameter could be e.g. in the range of 50-80 mm, such as about 70 mm. Preferably, the cables are to be made of high grade steel having an ultimate strength of approximately 1700 MPa. If necessary, e.g. in regions with relatively strong winds, a double set of cables can be used.

[0029] An embodiment relates to a building structure, wherein, when seen in top view, the radial cables are intersected at radially spaced-apart positions by a plurality of membrane cables running in a direction substantially parallel to the circumference of the tent structure. The membrane cables, e.g. totaling 2-6, for instance 4, for example spaced at a mutual distance of 5 m, allow the convexity of the tent structure to be selectively adjusted. E.g. by arranging the membrane cables around the radial cables, the individual bending angle of the radial cables can be adapted, such as over an angle of 5-10°, for instance approximately 8°. This can be done e.g. by increasing/decreasing the tension of each of the membrane cables. Thus, a significant flexibility can be achieved with respect to the final (spatial) design of the tent structure.

[0030] Analogously, an embodiment relates to a building structure, wherein the airdome comprises an airdome fabric. [0031] An embodiment relates to a building structure, wherein the airdome fabric comprises a layer with a heat-reflective foil. Again, excessive irradiation of sunshine or heat can be prevented to enter this way. [0032] An embodiment relates to a building structure, wherein the airdome fabric comprises an isolation layer with an aerogel. Such an aerogel is relatively light-weight and provides outstanding heat resistance properties. [0033] An embodiment relates to a building structure, wherein the airdome fabric comprises a layer with a phase change material for storing/releasing relatively large amounts of thermal energy, e.g. to create a chilled or heated airdome ceiling. In climates with heating demands the phase change material can be advantageously used to reduce necessary heating capacity.

[0034] An embodiment relates to a building structure, embodied as a stadium for playing sports.

[0035] Another aspect of the invention concerns an airdome for use in the aforementioned building structure, having a substantially concave shape with respect to an interior of the airdome during use, wherein the airdome comprises an airdome fabric.

[0036] An embodiment relates to an airdome, wherein the airdome fabric comprises a layer with a heat-reflective foil, having similar advantages as discussed with respect to the combined building structure as discussed in the foregoing.

[0037] Similarly, an embodiment relates to an airdome, wherein the airdome fabric comprises an isolation layer with an aerogel.

[0038] Analogously, an embodiment relates to an airdome, wherein the airdome fabric comprises a layer with a phase change material.

[0039] Another aspect of the invention relates to a tent structure for use in the aforementioned building structure, wherein an airdome can be arranged underneath the tent structure, wherein the tent structure can be arranged over substantially the whole of the airdome, when seen in top view, wherein the tent structure has a top and a circumference, the top being provided with an opening and being located at a greater height than the circumference of the tent structure, the circumference being placed at a vertical distance from the ground, the tent structure comprising a fabric and having a generally convex shape with respect to the airdome, wherein a convex side of the tent structure can be turned towards the airdome, wherein the convex side of the tent structure and an outer surface of the airdome are spaced-apart.

[0040] The above tent structure can both be used when an airdome is present underneath, but can also be used when the airdome is removed. E.g. when the airdome is used for playing sports, it can be removed afterwards, while the tent structure is left to stand at its current location. This allows the space underneath the tent structure to be used for other purposes afterwards, such as for comprising a market place or a park.

[0041] By physically disconnecting the tent structure from the airdome, the airdome can be removed without removing/modifying the tent structure itself. This significantly increases the useful life of the tent structure and especially of its materials.

[0042] Preferably, the tent structure is constructed from exchangeable or adaptable elements. E.g. openings can be realized this way or PV-cells can be added later on. By doing so, the tent structure can be conveniently adapted to the desired functionality of the area covered by the tent structure, in particular of the airdome underneath it.

[0043] Analogous to the combined building structure as discussed in the foregoing, an embodiment relates to a tent structure, wherein the vertical distance between the circumference and the ground is at most 10 m, preferably at most 5 m, more preferably at most 2 m.

[0044] Similarly, an embodiment relates to a tent structure, wherein the tent structure is supported near the top by a supporting pole extending downwards to a ground position. [0045] Again, an embodiment relates to a tent structure, wherein the tent structure comprises a plurality of tops with a corresponding plurality of openings, wherein a similarly corresponding plurality of supporting poles extend from the plurality of tops to a ground position. [0046] Additionally, an embodiment relates to a tent structure, wherein the plurality of supporting poles converge at a single ground position. [0047] Furthermore, an embodiment relates to a tent structure, wherein the plurality of supporting poles comprises at least three supporting poles.

[0048] An embodiment also relates to a tent structure, wherein the fabric of the tent structure comprises a layer capable of converting solar energy into electricity.

[0049] A further embodiment relates to a tent structure, wherein the fabric of the tent structure comprises a heat reflective membrane layer.

[0050] Another embodiment relates to a tent structure, wherein the fabric of the tent structure comprises a layer incorporating a solar warm water collecting system.

[0051] An embodiment relates to a tent structure, wherein the fabric of the tent structure comprises a layer transparent to daylight. [0052] Also, an embodiment relates to a tent structure, wherein the fabric of the tent structure is supported by a cable structure.

[0053] Correspondingly, an embodiment relates to a tent structure, wherein, when seen in top view, the cable structure comprises a plurality of radial cables running in a radial direction from the top towards the circumference of the tent structure, wherein, near the circumference, the cable ends are each attached to a connecting member installed in the ground. Preferably, the amount of cables equals the amount of connecting members.

[0054] Therein, adjacent radial cables can be spaced-apart at an angle of 10-15°, preferably approximately 12°.

[0055] Yet another embodiment relates to a tent structure, wherein, when seen in top view, the radial cables are intersected at radially spaced-apart positions by a plurality of membrane cables running in a direction substantially parallel to the circumference of the tent structure.

[0056] Preferably, the aforementioned airdome is cooled by activating the dome structure using chilled air (or nebulisation) and the 'Coanda effect' to create a climate ceiling effect without water in the dome structure.

[0057] Another advantage of the airdome, tent structure and the combined building structure comprising both, is that no use is made of rigid parts, allowing rapid disassembly and easy transport.

Brief description of the drawings [0058] Embodiments of a building structure according to the invention will by way of non-limiting example be described in detail with reference to the accompanying drawings. In the drawings:

[0059] Figure 1 shows a top view of a building structure according to the invention;

[0060] Figure 2 shows an exploded view of an exemplary embodiment of the airdome fabric;

[0061] Figure 3 shows an exploded view of an exemplary embodiment of the tent structure fabric;

[0062] Figure 4 shows a schematic, perspective view of an exemplary embodiment of the building structure, wherein the tent structure is supported near a plurality of tops by a plurality of supporting poles; and

[0063] Figure 5 shows a schematic side view of an exemplary embodiment of the building structurer; [0064] Figure 6 shows a schematic perspective view of an exemplary embodiment of the building structure, wherein the tent structure is supported near an outer circumference by a cone-shaped structure; [0065] Figure 7 shows a schematic perspective view of an exemplary embodiment of the building structure, wherein the tent structure has an elongated tunnel-like structure;

[0066] Figure 8 shows a schematic perspective view of an exemplary embodiment of the building structure, wherein the tent structure is shaped like a pin-cushion and is supported on the airdome by a plurality of supporting poles; and

[0067] Figure 9 shows a schematic perspective view of an exemplary embodiment of the building structure, wherein the tent structure is supported by a plurality of supporting poles having a symmetrical structure.

Detailed description of the invention

[0068] Figure 1 shows a building structure 1 according to the invention. The building structure 1 comprises an isolating airdome 2 fixedly attached to the ground 3. The building structure 1 comprises a covering structure 4 with a tent structure 5 arranged over substantially the whole of the airdome 2, when seen in top view. The tent structure 5 has a top 6 and a circumference 7, the top 6 being provided with an opening 8 and being located at a greater height than the circumference 7 of the tent structure 5. The circumference 7 is placed at a vertical distance H from the ground 3. The tent structure 5 comprising a fabric, which will be discussed later on. The tent structure 5 has a generally convex shape with respect to the airdome 2. A convex side of the tent structure 5 is turned towards the airdome 2. The convex side of the tent structure 5 and an outer surface of the airdome 2 are spaced-apart at a distance D. The distance D preferably is at least 0, 1 m. The vertical distance H between the circumference and the ground is at most 10 m, preferably at most 5 m, more preferably at most 2 m. [0069] The ground 3 below the airdome 2 is provided with an underground piping system 14, through which coolant is circulated, during use, for absorbing heat from the airdome 2. [0070] A preferred embodiment relates to a building structure 1 embodied as a stadium for playing sports, in particular soccer.

[0071] Figure 2 shows an exploded view of an exemplary embodiment of the airdome fabric 26. The airdome fabric 26 comprises a layer with a heat-reflective foil 27, attached to a cable structure 22. The airdome fabric 26 as shown also comprises an isolation layer with an aerogel 28. Furthermore, a layer with a phase change material 29 is shown.

[0072] Figure 3 shows an exploded view of an exemplary embodiment of the tent structure fabric 10. The fabric 10 of the tent structure comprises a layer capable of converting solar energy into electricity 18. The fabric 10 of the tent structure comprises a heat reflective membrane layer 19. The fabric 10 of the tent structure as shown also comprises a layer incorporating a solar warm water collecting system 20. The fabric of the tent structure furthermore comprises a layer transparent to daylight 21 or comprising translucent materials suitable for daylight penetration. The fabric 10 of the tent structure is supported by a cable structure 22, which will be discussed in more detail later on. If desired, the layer sequence can be adapted as required.

[0073] Figure 4 shows a schematic, perspective view of an exemplary embodiment of the building structure 1, wherein the tent structure 5 is supported near a plurality of tops 6, 6', 6" by a plurality of supporting poles 15, 15', 15", in this case three, wherein the supporting poles 15, 15', 15" extend downwards, from the tops 6, 6', 6", through an opening 16 in the airdome 2 to a ground position 17 within the airdome. In the embodiment as shown, the plurality of supporting poles 15, 15', 15" converge at a single ground position 17 within the airdome 2.

[0074] Figure 5 shows a schematic side view of a building structure 1, wherein, when seen in top view, the cable structure 22 comprises a plurality of radial cables 23 running in a radial direction from the top 6 towards the circumference 7 of the tent structure 5, wherein, near the circumference, the cable ends are each attached to a connecting member 24 installed in the ground 3. When seen in top view, in this embodiment, adjacent radial cables 23 are spaced-apart at an angle of 10-15°, preferably approximately 12°. When seen in top view, the radial cables 23 are intersected at radially spaced-apart positions by a plurality of membrane cables 25 running in a direction substantially parallel to the circumference 7 of the tent structure.

[0075] Figure 6 shows a schematic perspective view of a building structure 1 according to a further embodiment, wherein the tent structure 5 comprises a cable structure 22 having a configuration similar to the one illustrated in figure 4. The radial cables 23, extending in the radial direction from the top 6 towards the circumference 7, are connected at a location at the top 6 to a radial cone-shaped structure 9 for supporting the tent structure 5. The cone-shaped structure 9 is provided with an opening 8, defining a ring-shaped outer circumference 7' of the cone-shaped structure 9. As shown, the cone-shaped structure 9 comprises a plurality of radial cables 23 ' running in a radial direction from the top circumference 7' towards the inner side of the tent structure 5, through the opening 16 in the airdome 2, and converging at a ground position (not shown) inside the airdome 2. The cone-shaped structure 9 comprises a plurality of membrane cables 25' running in a direction substantially parallel to its outer circumference 7'.

[0076] Figure 7 shows a schematic perspective view of a building structure 1, wherein the tent structure 5 has an elongated tunnel-like structure with multiple smaller 'tents'. The building structure 1 comprises a row - having a row direction - of inverted U- shaped beams that enclose the airdome 2 from (opposite) side to side. The inverted U- shaped beams 25' are placed at a distance from each other and extend in a direction transversal to the row direction, dividing the tent structure 5 in such a way that the tension between the tent structure 5 parts is evenly distributed over the inverted U- shaped beams 25'. The top 6 of the tent structure 5 is provided with an elongated opening 8 extending in the row direction. The inverted U-shaped beams 25' can comprise partially or wholly inflated airbeams, wherein the pressure in each of the beams may vary depending on the outside and/or inside climate conditions. In this manner, the forces exerted on the tent structure 5 will be equally distributed over the U- shaped beams 25' in correspondence with the so-called 'Tensairity principle' . Other constructions, such as comprising steel or wood, are of course also conceivable. [0077] Figure 8 shows a building structure 1 according to a further embodiment according to the present invention. The building structure 1 comprises a plurality of supporting poles 15, which support the tent structure 5 on the airdome, creating a series of small tents that cover the airdome 2 and that provide a padded appearance to the tent structure 5. The supporting poles 15 are arranged in a symmetrical manner resembling a pin-cushion. The lengthwise edges 7 of the tent structure 5 are placed at a vertical distance from the ground 3. The connection between the supporting poles 15 and the tent structure 5 is a weather-tight connection, while an elongated opening 8 extends in a direction substantially parallel to the lengthwise edges 7 of the airdome 2. [0078] Figure 9 shows a building structure according to the present invention, wherein the tent structure 5 is supported by the plurality of supporting poles 15, 15', 15", in this case three at each side of the airdome 2. When viewing the building structure 1 in length direction the building structure 1 resembles the horns of a bull. The plurality of supporting poles 15, 15', 15" extend from the tops 6, 6', 6" towards a location adjacent to the lengthwise edges of the airdome 2. In the illustrated embodiment, the plurality of supporting poles 15, 15', 15" are each associated with an opening 8, 8', 8". The opening 8, 8', 8" is located at highest point of the top 6 of the tent structure 5. The tent structure 5 again comprises radial cables 23, 25, 25' being provided in a configuration similar to the ones as shown in the embodiments of figures 4 and 5. Multiple individual tent structures are thus formed, connected to each other in lengthwise direction.

[0079] Thus, the invention has been described by reference to the embodiments discussed above. It will be recognized that these embodiments are susceptible to various modifications and alternative forms well known to those of skill in the art without departing from the spirit and scope of the invention. Accordingly, although specific embodiments have been described, the above described embodiments are examples only and are not limiting upon the scope of the invention. Reference numerals

1. Building structure

2. Airdome

3. Ground

4. Covering structure

5. Tent structure

6. Top

7. Circumference

8. Opening

9. Cone-shaped structure

10. Tent structure fabric

11. Convex side of tent structure

12. -

13. Intermediate position between top and circumference

14. Underground piping system

15. Supporting pole

16. Opening in airdome

17. Ground position within airdome

18. Tent fabric layer capable of converting solar energy into electricity

19. Tent fabric heat reflective membrane layer

20. Tent fabric layer incorporating a solar warm water collecting system

21. Tent fabric layer transparent to daylight

22. Cable structure

23. Radial cable

24. Connecting member

25. Membrane cable

26. Airdome fabric

27. Airdome fabric layer with a heat-reflective foil

28. Airdome fabric isolation layer with an aerogel

29. Airdome fabric layer with a phase change material H. Vertical distance between circumference of tent structure and ground D. Distance between convex side of the tent structure and outer surface of the airdome