Assembly of structural elements, structural element and use of such an assembly
The present invention relates to an assembly of identical structural elements, wherein each structural element: • is dome-shaped;
• has a domed roof at the top;
• viewed from above, looking onto the domed roof, has a square peripheral shape;
• has four supporting legs provided in the corners of the square peripheral shape, running downwards from the domed roof and supporting the domed roof; • has four arches laterally joining the supporting legs, the outward-facing arch edges of which are so shaped that they are able to connect, in particular are able to connect to provide a seal, onto an outward-facing arch edge of an identical structural element; wherein the assembly comprises at least one continuous layer of structural elements joined to one another via their arch edges.
A structural element of this type is disclosed in European Patent Application 0 969 157 and also in the Italian Patent Application 1 253 374 and Italian Design Application PN930000012, cited therein, all originating from the same Applicant. The structural elements are intended for the creation of hollow spaces beneath floors of both residential and commercial buildings. To this end a number of said structural elements, all having the supporting legs facing downwards, are coupled laterally to one another by means of the arch edges so that a layer of a matrix-like pattern of such structural elements is produced. Because the arch edges of adjacent structural elements overlap one another and connect onto one another, a large space interrupted only by the supporting legs is produced below the arch elements. The matrix-like layer of the structural elements, the supporting legs of which are facing downwards, is then covered from above with a layer of concrete poured thereon. During this operation this concrete is able to flow into the spaces that have been formed between each of the four supporting legs of structural elements directly adjoining one another at a corner in order thus, after setting, to be able to bear directly on the same substrate as that on which the supporting legs of the structural elements bear. The structural elements form so-called lost shell components here. The open space created below the structural elements can then be used for wiring, pipework and tubes or pipes as well as for ventilation. It is also known to use a layer of such structural
elements in horticulture and in particular in greenhouse construction. Specifically, such a layer of structural elements can be placed beneath a greenhouse or in some other way beneath cultivation soil in order to create a storage chamber for rainwater beneath the cultivation surface instead of, as is customary, alongside the cultivation surface. A system of this type is marketed by aterblock B.V. under the name "Watersheli" and according to information from Waterblock B.V. is also the subject of a European Patent Application, which appears to have not yet been published. All these known systems with a layer of identical structural elements require that the substrate on which the supporting legs of the structural elements bear is a pre-poured concrete floor, in particular a moisture-tight concrete floor. In order, with such a matrix-like layer of structural elements, to vary, in particular to enlarge, the height of the intermediate space to be created therewith, the supporting legs have to be extended. The disadvantage of this is that in practice the extension of the supporting legs will be limited and that this necessitates the marketing of structural elements having different supporting leg lengths. The aim of the present invention is to provide an improved assembly of the type mentioned at the outset, with which, on the one hand, it is possible to dispense with a liquid-tight substrate to be produced separately, such as the bottom concrete layer known from the state of the art, and with which, on the other hand, it is possible to increase the volume of the intermediate space to be created by means of the structural element without the need to have recourse to structural elements with a longer supporting leg length for this purpose.
According to the invention, the abovementioned aims can be achieved in that the assembly comprises at least two of said continuous layers and in that the supporting legs of the structural elements of the one layer are oriented in the opposite direction to the supporting legs of the structural elements of the other layer. By, as it were, placing one layer upside down compared with the state of the art, with the supporting legs oriented upwards, a closure is created in the direction of the layer located underneath by said upside down bottom layer of structural elements. The second layer of structural elements can then be placed with the supporting legs facing downwards on top of said bottom layer of structural elements, which second layer then provides a closure in the upward direction. An intermediate space is then formed between the first and second layer. Insofar as this is desired, a second or optionally even third, etc., pair of layers can then be placed on top of this bottom pair of layers. In this way the volume of the hollow space to be created can ever
further increase with the number of pairs of layers to be placed on top of one another.
The arch edges adjoining one another can be coupled to one another by means of flanges provided on said arch edges, which flanges are in contact with one another and can be held together by means of pins or clamps. However, according to the invention it is advantageous if the arch edges facing outwards are so shaped that they are able to overlap, preferably are able to snap into an outward-facing arch edge of an identical structural element.
According to a further advantageous embodiment of the invention, the domed roofs of the structural elements are provided with a central opening, which opening can be closed, in particular by a removable plug. Such an opening makes it possible for a passage to be provided for feeding cables, wiring etc. into the space delimited by the structural elements. Furthermore, such an opening makes it possible to feed a liquid medium, such as liquid or gas, into the space enclosed by the structural elements [lacuna] from said space to the outside. This can, for example, be advantageous when the assembly of identical structural elements is used to obtain a storage chamber for heat or cold.
According to a first advantageous embodiment of the assembly according to the invention, the one and the other layer are mutually offset in such a way that the free ends of the supporting legs of the structural elements of the one layer are always in contact with the centre of a domed roof of a structural element of the other layer and, conversely, the supporting legs of the structural elements of the other layer are always in contact with the centre of a domed roof of a structural element of the one layer. This has the advantage that the compressive strength of such a pair of layers consisting of one and another layer increases because the supporting legs create more bearing points per unit surface area as a consequence of the mutual offset. According to another advantageous embodiment of the assembly according to the invention, the free ends of the legs of the one layer bear on the free ends of the legs of the other layer. In this way it is possible, using a pair of layers consisting of a one and another layer, to obtain doubling of the volume of free intermediate space obtained by, compared with the state of the art, merely placing a second upside down layer below the single layer from the state of the art.
In the case of the use of structural elements having an opemng in the domed roofs, it is furthermore advantageous according to the invention if a tube extends through, or at least between, the openings of domed roofs having insides facing one another. Such a tube
provides additional reinforcement against compressive stresses. A further advantage is that when pouring a concrete layer onto the assembly according to the invention it will be possible for the tube to fill with concrete and thus to provide a sort of foundation column. The said tube can extend through a series of more than two openings located one above the other. The tube can also extend beyond the openings, for example as far as into the substrate.
According to a further advantageous embodiment of the invention a reinforcing strip or reinforcing layer is provided that joins the free ends of legs located in one line, or located in one plane, to one another. Such a strip or layer prevents the ends of the supporting legs bending apart sideways when a tensile stress is absorbed.
According to a further advantageous embodiment of the invention, the assembly comprises one or more partitions that are placed in a plane delimited by the supporting legs and associated arches of two structural elements placed with a (sic) free ends of the legs on top of one another. By means of such partitions it is possible to divide the space delimited by the structural elements into compartments, to provide the space delimited by the structural elements with a labyrinth, or optionally to provide the assembly with some additional compressive strength. When the assembly according to the invention is used below groundwater level, such partitions can, for example, usefully be used to counteract too free a flow of groundwater by erecting barriers herein by placing partitions in suitable locations.
According to a further advantageous embodiment of the invention, the free ends of the legs of the structural elements are provided with feet which extend parallel to the bearing plane. With this arrangement the four feet, which always meet, of directly adjoining structural elements of one layer leave a passageway formed between them open. Such a passageway makes it possible for concrete poured on top of the top layer also to be able to flow into the spaces formed by the upright legs of the bottom layer. In order with this arrangement mutually to fix the bottom and top layer to prevent shifting, it is preferable according to the invention if the feet, located opposite one another, of the structural elements of, in each case, the one and other layer are joined to one another for fixing to prevent shifting in a plane spanned by said four feet of a structural element. According to the invention such a join can be obtained in a simple and reliable manner by means of a pin extending through a pair of feet located opposite one another.
So that the layers of structural elements can be stacked back-to-back, that is to say
with the domed roofs on top of one another, securing them, inter alia, against mutual shifting, it is preferable according to the invention if the domed roof of each structural element is of pyramid-shaped construction or at least is provided with a pyramid-shaped top section and if the square base surface of said pyramid shape and the square peripheral shape of the structural element are turned through 90° with respect to one another about a common perpendicular bisector. In this way engagement of pyramid-shaped parts with one another is achieved between the layers lying back-to-back with the domed roofs on top of one another. In this context the invention also relates to a structural element that is particularly suitable for such an assembly, wherein the structural element: • is dome-shaped;
• has a domed roof at the top;
• viewed from above, looking onto the domed roof, has a square peripheral shape;
• has four supporting legs provided in the corners of the square peripheral shape, running downwards from the domed roof and supporting the domed roof; • has four arches laterally joining the supporting legs, the outward-facing arch edges of which are so shaped that they are able to connect, in particular are able to connect to provide a seal, onto an outward-facing arch edge of an identical structural element; characterised in that the domed roof of a structural element is of pyramid-shaped construction or at least is provided with a pyramid-shaped top section and in that the square base surface of said pyramid shape and the square peripheral shape of the structural element have been turned through 90° with respect to one another about a common perpendicular bisector.
According to a further aspect, the invention also relates to a structural element that is particularly suitable for an assembly in which openings, which may or may not be closed off by a plug, have been provided in the domed roofs. According to this aspect, the present invention relates in particular to a structural element that:
• is dome-shaped;
• has a domed roof at the top; • viewed from above, looking onto the domed roof, has a square peripheral shape;
• has four supporting legs provided in the corners of the square peripheral shape, running downwards from the domed roof and supporting the domed roof;
• has four arches laterally joining the supporting legs, the outward-facing arch edges
of which are so shaped that they are able to connect, in particular are able to connect to provide a seal, onto an outward-facing arch edge of an identical structural element; characterised in that the domed roof is provided with and (sic) central opening. So that the opening can also be closed off, in this context it is preferable according to the invention if said opening is provided with a plug. For further reinforcement it is advantageous with this arrangement if a tube extends in the space delimited by the supporting legs, from the opening to the bottom ends of the supporting legs. This tube can optionally have been produced in advance as an integral whole with the structural element. The tube can also be provided subsequently as a separate element.
According to a further aspect, the present invention also relates to the use of an assembly according to the invention as a filler body in a mound of earth, such as in a dyke or road embankment, in particular as a filler body in an extension of a dyke or road embankment. According to an advantageous embodiment the assembly according to the invention in this context is used in particular for storing heat extracted from a pavement.
According to yet a further aspect, the present invention relates to the use of an assembly according to the invention for storing heat or cold.
According to yet a further aspect, the present invention relates to the use of an assembly according to the invention as a heat exchanger. According to yet another further aspect of the invention, the latter relates to the use of an assembly according to the invention as a float. By sealing two layers of structural elements according to the invention lying on top of one another at the outer periphery of the layers, a relatively large volume of float is obtained.
The present invention will be explained in more detail below with reference to the illustrative embodiments shown diagrammatically in the drawing. In the drawing:
Fig. 1 shows a diagrammatic perspective view of a structural element according to the state of the art, which structural element can be the basic element of an assembly according to the invention and can also be a basic element in the use according to the invention;
Fig. 2 shows a structural element according to the invention, which is suitable for use as basic element for an assembly according to the invention and can also be a basic element in the use according to the invention;
Fig. 3 shows an assembly according to the invention where the supporting legs, facing one another, of two layers bear on one another; where Fig. 3a is a perspective view of two
such layers and Fig. 3b is a detail of a plan view at the point where four supporting legs of different structural elements meet; and
Fig. 3c shows a diagrammatic side view, in section, of such an assembly embedded in a concrete layer; Fig. 4 shows an assembly according to the invention where the supporting legs, oriented in opposing directions, of two layers each make contact with the domed roof of a structural element of another layer; where Fig. 4a is a perspective view of two such layers and Fig.4b is a diagrammatic side view, in section, of such an assembly embedded in concrete; Fig. 5 shows, highly diagrammatically, in section, the use of an assembly according to the invention in an extension to widen a road or dyke;
Fig. 6 shows, highly diagrammatically, in section, yet a further use of an assembly according to the invention for storing heat extracted in (sic) a pavement and optionally releasing the stored heat to the pavement again; and
Fig. 7 shows, highly diagrammatically, a side view of two layers of structural elements lying back-to-back on top of one another, where each structural element has a pyramid- shaped top section.
Fig. 1 shows, highly diagrammatically, a single structural element that can be used in an assembly according to the invention. As can be seen, the structural element 1 is dome-shaped and has a closed domed roof 2 at the top. Viewed from above, looking onto the domed roof 2, the structural element 1 has an approximately square peripheral shape 3. The structural element 1 also has four supporting legs 5, which are provided at the corners of the square peripheral shape 3, run downwards from the domed roof 2 and support the domed roof 2. Furthermore, the structural element 1 has four arches 8 laterally joining the supporting legs 5, the outward-facing arch edges 6, 7 of which arches 8 are shaped in such a way that they are able to connect onto, preferably to snap into, with an overlap, an outward-facing arch edge 7 and 6, respectively, of an identical structural element. In order to be able to achieve this connecting onto, and preferably snapping into, each structural element 1 always has two types of arch edges, i.e. the type 6 arch edge and the type 7 arch edge. These arch edges 6, 7 are, as is indicated in Fig. 1 by means of the numbering 6, 7, always so positioned that the arches 8 having arch edges 6 adjoin one another via a common supporting leg 5 and that the arches 8 having arch edges 7 also adjoin one another, always via a common supporting leg. Thus the structural elements 1 can very easily be coupled to one another to form a layer, which layer can be of essentially unlimited dimensions. In order to able, with this arrangement, to achieve
simple and error-free coupling, it will also be advantageous if the structural elements 1 are provided with a position marker, for example an arrow that is provided on the top of the domed roof and always points in the same direction. When making up the structural elements 1 into a layer it is then necessary only to take care that the arrows all point in the same direction. As Fig. 1 shows, the supporting legs 5 have triangular feet 9 at their bottom ends. In the case of the structural element according to the state of the art, the consequence of these triangular feet 9 is that when making up a layer the feet 9 of four supporting legs 5, which meet, of four different structural elements completely close off the intermediate space between said four supporting legs at the feet 9. As far as such structural elements as shown in Fig. 1 are concerned, reference can be made, inter alia, to EP 969 157 and also to the "Italian Patent Specification no. 1 253 374 cited therein and Italian Design Application no. PN 93000012, also cited therein, all of which originate from the same Applicant. All these structural elements known from the state of the art can readily be used in the assembly according to the invention. In this context these cited publications must therefore also be considered as incorporated in this application by reference.
Deviating from the state of the art known to the Applicant, an opening 14 is provided centrally in the domed roof 2, which opening 14 can be closed off by a plug 15 indicated diagrammatically by broken lines. Pipes and tubes can, for example, be inserted through the opening 14. The opening 14 can also be used as a flow passage for a fluid. Fig. 2 shows a structural element specifically in accordance with a particular embodiment of the invention. This structural element differs from the structural element according to Fig. 1 essentially in respect of three points. These three points of difference are:
• the domed roof 2 is provided with a pyramid-shaped top section 4;
• the feet 9 on the supporting legs 5 are provided with an opening for a pin 11 ; • instead of being triangular, the feet 9 on the supporting legs 5 are truncated at the point [lacuna] triangular longitudinal edge 10. Said three points of difference can be used completely independently of one another in a structural element according to the invention, but all three can also be used at the same time in a structural element and also in any arbitrary combination of two points of difference. In the case of the structural element according to Fig. 2, the first point of difference, i.e. the pyramid-shaped top section 4, has a square base shape 12 that has been turned through 90° with respect to the square peripheral shape 3 of the structural element 1. The turn is around the common central axis of symmetry 13. As is illustrated in Fig. 7, the advantage of
the pyramid-shaped top section 4 is that two layers lying back-to-back on top of one another engage in one another by means of their pyramid-shaped top sections 4 and sMfting of said two layers 70 and 71 in a plane horizontal and perpendicular to the plane of the drawing is thus prevented or at least counteracted. The second point of difference, i.e. the opening 11 in preferably each foot 9 provides the possibility of anchoring two structural elements 1, the supporting legs 5 of which are oriented in opposing directions, to one another. If such structural elements are positioned with the feet 9 of the one structural element 1 in contact with the feet 9 of the other structural element 1, opposing feet 9 can then be secured against mutual shifting by inserting pins in the openings 11. This is, in particular, highly useful in the case of the assembly as shown in Fig. 3.
The third point of difference, i.e. the fact that the triangular shape of the feet 9 is truncated along the line 10, has the advantage that a passage 13 (see Fig. 3b) remains free between four feet 9 of four supporting legs 5, which meet, of four different structural elements 1. In particular, in the case of the assembly according to Fig. 3 this has the advantage that here the material, such as concrete, in which the assembly is embedded is able to flow through. Better filling of the spaces 14 (see Fig. 3, in particular Fig 3c) between adjacent supporting legs 5 of adjacent structural elements 1 from the bottom layer components 30 (sic) can be achieved in this way. Fig. 3 a shows, diagrammatically, a perspective assembly according to the invention, where a bottom layer 31 of structural elements 1 with the supporting legs pointing upwards supports a top layer 30 of structural elements 1 with the legs pointing downwards, the feet 9 of the structural elements 1 of the top layer 30 bearing on the feet 9 of the structural elements 1 of the bottom layer 31. A pin 32 that has been inserted through the holes 11 in the opposing feet 9 of structural elements from different layers is shown in Fig. 3a and also Fig. 3c. It should be clear that not every pair of opposing feet 9 have to be joined to one another by means of a pin 32. In this context it will also be clear that not every foot 9 has to be provided with an opening 11 of (sic) a pin. From the production engineering standpoint it will usually be preferred to provide each foot 9 with an opening 11 for a pin and on efficiency grounds to insert a pin here and there through the opposing openings 11 when making up the assembly. Fig. 3b shows, as a detail, a plan view (according to arrow 33 in Fig. 3a) of the region where the supporting feet 9 of supporting legs 5 of four different structural elements 1 meet. The passage 13, which has already been mentioned and is obtained by making the triangular
feet 9 truncated along line 10, can also clearly be seen in this figure.
Fig. 3c shows a diagrammatic side view, in section, of the assembly from Fig. 3a when embedded in concrete. In practice, a bottom concrete layer 34 will first be provided, the assembly according to Fig. 3 a will be placed on top of this and a concrete layer 35 will then be poured over the top. As a consequence of the passages 13, the concrete is then also able to pass into the spaces 14 between the supporting legs 5 of the bottom layer 31. It should furthermore be clear that although concrete is referred to in Fig. 3c this can also be another material, such as earth, sand or gravel. The use of a material that can be poured in the fluid state and then sets is preferred insofar as this usually leads to a more compact whole and better enclosure of the space 35 between the bottom layer 31 and top layer 30.
Fig. 3 c also shows, diagrammatically, that a tube 36 can be inserted through openings 14 located opposite one another in domed roofs 5. Because this tube 14 (sic) is also filled with concrete, a strong supporting column 37 is obtained. As is indicated by broken line 38, the tube 36 can continue as far as into the substrate 39. It is also possible to accommodate the tube 36 in a duct system and to feed a fluid through this system that exchanges heat with the medium that is in space 35.
Fig. 4 shows a further assembly according to the invention. The assembly shown in Fig. 4a in perspective and in Fig. 4b in section embedded in concrete consists of a bottom layer 41 of structural elements 1 and a top layer 40 of structural elements 1. As can clearly be seen in particular in Fig. 4b, every four supporting legs 5, which meet, of the bottom layer 41 of structural elements 1 jointly support approximately the centre 42 of a structural element 1 from the top layer 40 and vice versa. The advantage of the assembly according to Fig. 4 is that in this assembly a relatively high supporting column density (here each supporting column is formed by four supporting legs of different adjoining structural elements 1 from one layer) is produced and a higher compressive strength is thus obtained. The assembly according to Fig. 4 is also suitable, as is shown in Fig. 4b, for embedding in concrete or another material (just as is the case in Fig. 3). In the case of concrete, once again a bottom layer 44 will usually first be laid on which the assembly of layers 40 and 41 is placed, in order then to pour a concrete 45 over the top. It should be clear both in the case of Fig. 3 and in the case of Fig. 4 that the bottom concrete layer 34 and 44, respectively, could optionally be omitted.
Fig. 4b also shows, diagrammatically, that by providing an opening 14 in a domed roof a concrete column 46 can be obtained that joins the bottom layer 44 and top layer 45 together
and thus improves the load-bearing capacity.
Fig. 5 shows, highly diagrammatically, one use of the assembly according to the invention. For the purposes of illustration, use is made of two assemblies according to Fig. 3 lying on top of one another on the left-hand side of Fig. 5 and of two assemblies according to Fig. 4 lying on top of one another on the right-hand side. Fig. 5 shows a road embankment 50 having thereon a central reservation 51 and a carriageway 52 on either side. To widen this road embankment 50, which equally well could be a dyke, an extension 54, 55 is formed on one side or, as is shown on either side. The extensions 54, 55 form widening zones for the original embankment 50. In the case of such widenings, usually earth material, etc. is deposited on one side of or on either side of the original embankment 50 in such a way that the original embankment 50 is widened. The problem with this procedure is usually that the substrate and the foundations of the original embankment 50 have not been designed to take account of this. As a consequence of the high weight of such extensions, these sometimes tend to break away from the original embankment 50, or at least there is a tendency for cracks to be produced in the pavement, as a consequence of, inter alia, subsidence. Use of an assembly according to the invention now has the advantage that the weight of such an extension can be appreciably reduced. A further advantage of use of the assembly according to the invention is that the extensions can be built more rapidly. This is because a lorry containing a large number of nested structural elements supplies a much greater volume for the extensions 54, 55 than a lorry loaded with earth material. The load-bearing capacity can be improved by providing one or more tubes 36 (left) which join aligned centres of domes to one another, in particular if the tubes are filled with poured concrete or something similar. On the right-hand side of Fig. 5 something similar can be achieved by providing central openings in domed roofs located one above the other and pouring preferably concrete or something similar through these openings.
Fig. 6 shows yet a further application of the assembly according to the invention. In Fig. 6 the assembly according to Fig. 3 is shown, although the assembly according to Fig. 4 could also be used here.
Fig. 6 shows a road embankment with an asphalt road 61 with central reservation 62 and on either side carriageways 63 thereon. Pipes or ducts 64 through which a liquid, in particular water, is able to flow have been laid in the pavement 61. This liquid is heated under the influence of solar heat, after which the liquid can be stored for later use of the stored heat. The assembly 30, 31 now provides a storage buffer for said heat by means of its intermediate
space 35. Transport from the pipes 64 to the storage chamber 35 takes place via lines 65, 66 and one or more pumps 67. Under wintry or colder conditions it is now possible to heat the pavement 61. hi this way it is, in particular, possible appreciably to reduce the temperature fluctuations of the pavement 1 throughout the year, which appreciably benefits the life of the pavement 61.
Fig. 7 shows, highly diagrammatically, the back-to-back positioning of a bottom layer 71 and top layer 70 of structural elements according to Fig. 2. Here the pyramid-shaped top sections 4 as it were hook into one another to counteract shifting of the layers 70, 71 with respect to one another. The layers 71, 70 from Fig. 7 can, for example, be considered to be the back-to-back layers 30, 31 on the left-hand side of Fig. 5 or the back-to-back layers 40, 41 located on top of one another on the right-hand side of Fig. 5.
Figs. 6 and 7 both also show partitions 72 which are provided between the supporting legs and associated arches in order to close off the surface defined by these, h the embodiment according to Fig. 6 the two partitions 72 can optionally be combined in a one- part partition instead of the two-part embodiment shown. With a suitably chosen profiled edge, the partitions 72 can be fixed in a simple manner between the arches and legs so that they fit.
As, in particular, Figures 4, 5, 6 and 7 show, the assembly according to the invention provides a honeycomb-like three-dimensional structure. The space 35 or spaces 35 delimited by this structure can not only be filled with liquid, gas, suspensions, etc., as aheady indicated, but according to the invention can advantageously also be filled with solid compositions, hi what is a highly advantageous manner, such a composition can be or comprise a sound- insulating material, such as, for example, mineral wool, glass wool, a hardened foam, etc. When used as or in a dyke-like body, an assembly according to the invention filled with insulating material gives, for example, a noise barrier of relatively lightweight construction to screen, for example, a residence or residential estate from traffic noise or other noise. Incorporated underneath a pavement (see Figure 6 and also Figure 5), an assembly according to the invention filled with insulating material is able to improve the noise-reducing characteristics of the pavement.