A CONNENCTION MEANS OF A BUILDING STRUCTURE AND A METHOD OF USING SAME
The present application relates to a connecting means. More particularly, it relates to a building structure connecting means and a method for connecting an end portion of at least one first building element to an end portion of at least one second building element.
The first building element may for example be a slab element, wherein a plurality of such slab elements arranged side by side may provide a floor or roof in a building. Such a slab element has a length defined by first end portions, a width defined by second end portions and a thickness defined by a top side and a bottom side. The second building element may for example be a support such as a wall, a column, a supporting beam or a foundation configured for supporting at least end portions of the first building element.
A person skilled in the art will know that slabs and supports have to be interconnected in order to achieve required stability. For a building structure comprising steel elements, required stability is typically provided by means of welded and/or bolted connections. For a building structure made of concrete cast in situ, required stability may typically be provided by means of reinforcement bars interconnecting the elements such as walls and floors.
Buildings made of concrete may be made from prefabricated elements, wherein floors or roofs are made of precast slab elements or "beams" placed side by side to form a slab. A concrete wall is typically made by placing two or more wall elements side by side, oftentimes interconnected by means of tongue and groove arrangements.
Prior art concrete elements may typically have a density in the order of 2400-2500 kg/m<3>. Such a high density is encumbered with several drawbacks. One of the drawbacks is that handling such elements which may weigh several tonnes requires relatively powerful lifting equipment. At a building site it may be problematic to arrange access for powerful lifting equipment that might be required during installation of the slab elements and wall elements. Another drawback related to heavy structures is restrictions on the axle pressure permitted on the road network, which may result in more trips from the manufacturer to the building site. In places where it is difficult to provide lifting equipment of sufficient capacity, the drawback of heavy, prefabricated slab elements is even greater. If, in addition, the road standard is poor, road transport may at best be challenging.
A person skilled in the art will know that a building structure that includes building elements of a high dead load, for example the above-mentioned solid slab and wall elements, may be considerably more vulnerable than structures having a lower density, in natural disasters such as earthquakes. This, together with the infrastructure and limited access to suitable lifting equipment, may be an explanation of the fact that there is relatively little use of slab elements of the abovementioned kind in some countries and regions.
In order to provide required connection between such prefabricated wall elements and between wall elements and slab elements, so-called "welding plates" are commonly used. In such a case, welding plates have to be provided mutually spaced prior to pouring concrete into a formwork. During erection, abutting welding plates are welded together to provide the required connection. However, such a connection is not considered capable of transferring bending moments between a wall element and a slab element. A slab thus has to be designed as freely supported, i.e. a slab supported on the ends and free to rotate and have no moment resistance.
Further, a connection provided by means of welding plates requires both an exact positioning of the welding plates in the formwork prior to pouring of concrete, and a comprehensive check of the positioning of the elements prior to welding.
Publication JP H 111440994 A discloses a joint device to provide a connection between two adjacent end portions to prefabricated retaining wall elements or prefabricated culvert elements disposed in series. The joint device comprises an I-beam adapted to be inserted into grooves arranged in each of the end portions of two subsequent prefabricated elements to be connected. After the I-beam is inserted into the grooves, an elastic material is filled into an annulus between the I-beam and the grooves. A primary purpose of the elastic material is to enhance resistance against for example an earthquake. A further purpose of the elastic material is to provide a sealing in the wall and to protect the I-beam against corrosion.
Publication US 2006/236627 A discloses an apparatus and method for interconnecting concrete precast floor and wall panels is provided. The apparatus includes an adjustable connector with a captive nut that is embedded into a wall panel. A floor panel that includes an aperture integrated therethrough is placed adjacent to the adjustable connector wherein the captive nut therein may be positioned in line with the aperture. A threaded rod is then placed through the aperture of the floor panel and a nut is placed thereon thus providing a secure interconnection between the floor panel and the wall panel.
Publication EP 0165222 A2 discloses a concrete element for constructing a structural floor. The concrete element has a prefabricated base slab of concrete supporting the reinforcement of the element, and a concrete slab cast onto said base plate. The cast-on slab consists of an upper layer of concrete having a compressive strength of at least 30 MPa (after 28 days) and a density of at least 2,300 kg/m<3>, and of a lower layer of lightweight aggregate concrete having a density of 600-800 kg/m<3>.
Publication NO 333001 B1 discloses a building element made from a light concrete material containing at least 50 % by volume expanded plastic material. The building element Is provided with lifting devices which each are anchored to one mesh reinforcement in the building element in at least six points. The building element is provided with tensile reinforcement only.
Publication W02001/25651 A1 discloses a connecting element for joining two support members absorbing tensile forces. The connecting element comprises at least a first and a second casing body with a through-hole for receiving the respective support members.
The invention has for its object to remedy or to reduce at least one of the drawbacks of the prior art, or at least to provide a useful alternative to prior art.
The object is achieved through features, which are specified in the description below and in the claims that follow.
The invention is defined by the independent patent claims. The dependent claims define advantageous embodiments of the invention.
According to a first aspect of the present invention, there is provided a connection means for a building structure for connecting an end portion of at least one first building element having a thickness, to an end portion of at least one second building element, the first building element and the second element being made from concrete wherein an aggregate of the concrete comprises particulate expanded polystyrene. The connecting means comprises:
- a first joint element connected to and forming part of the end portion of the first building element; the first joint element having a length substantially corresponding to the thickness of the first building element;
- a second joint element connected to and forming part of the end portion of the second building element;
wherein each of the first building element and the second building element include at least two spaced-apart lattice girders, each lattice girder extending at least in a two-dimensional extent between the end portions of the building elements, the at least two spaced-apart lattice girders being connected at an upper portion and at a lower portion to an upper mesh reinforcement and a lower mesh reinforcement, respectively, and wherein the first and second joint elements are fixed, by means of welds, to a portion of the reinforcement of the first and second building elements, respectively, so that tension and compression forces in the first building element and the second building element are carried substantially by the reinforcement and transferred via the welds to the first joint element and the second joint element, and wherein the connection means further comprises at least one elongate member for slidable engagement with at least one of the first joint element and the second joint element, such that relative movement between the first joint element and the second joint element in at least one direction is prevented.
The elongate member may have a length exceeding the length of the first joint element. This has the effect that each of the at least one elongate member being slid into engagement with the first and second joint elements provides a rigid connection capable of transferring bending moment. The structure comprising at least one first building element and at least one second building element comprising the first and second joint elements, respectively, may therefore be designed as a rigid frame structure.
In a first embodiment, the elongate member may be a girder having an H- or I-girder section. At least the first joint element may be provided with a recess for receiving a flange of the girder and a slot for receiving a web of the girder. Preferably, the slot extends through at least one end portion of the first joint element, thereby being arranged to be able to allow sliding movement of the elongate member or girder relative to the first joint element. However, a slot extending through both end portions of the first joint element allows an elongate member to extend from both end portions and is preferred as this gives a greater range of use.
The second joint element may comprise a cavity for receiving and supporting an end portion of the elongate member. Thus, the second joint element may provide an enclosure for the end portion of the elongate member. The second joint element may be provided with a bottom plate for supporting an end face of the elongate member.
In a second embodiment the elongate member may be a bolt configured for receiving a nut for providing a bolted connection between at least one of the first joint element and the second joint element.
The first joint element may comprise a box section integrated in the end portion of the first building element. The box section is provided with at least one aperture for receiving the bolt.
The second joint element of the connection means may comprise a plate member forming a part of the end portion of the second building element, the plate member provided with at least one aperture mating with the aperture in the box section. Thus, the bolt may connect the box section with the plate member.
The first building element may be a slab element, and the second building element may be a support for supporting the slab element. The slab element may form part of a floor and the support may form part of a wall. However, the support may alternatively or additionally be arranged on top of the first building element, i.e. being supported by the slab element. Thus, the connection means according to the present invention may provide a rigid connection between a first building element, such as a floor element, and a second building element, such as a wall element, supporting the first building element, and/or between said first building element and a further second building element being supported by the first building element, i.e. wherein the second building element is arranged on top of the first building element.
The first building element and the second building element are, as stated above, made of concrete wherein an aggregate of the concrete comprises particulate expanded polystyrene. The building elements are prefabricated.
Therefore, in order to reduce a dead load of the first building element and the second building element, an aggregate of the concrete may comprise particulate expanded polystyrene.
Patent application PCT/NO2016/050083 to the present applicant, discloses a plate-shaped slab element for use as a floor in a building. The slab has a length defined by first end portions, a width defined by second end portions and a thickness defined by a top side and a bottom side. The slab element is made from concrete with an aggregate comprising an expanded plastic material, and the slab element is provided with reinforcement comprising an upper mesh reinforcement and a lower mesh reinforcement. The slab element is supported, at least in portions of the first end portions, by a supporting element. The slab element includes at least two spaced-apart lattice girders, each extending at least in a two-dimensional extent between the first end portions. The at least two spaced-apart lattice girders are connected at an upper portion and at a lower portion to the upper mesh reinforcement and the lower mesh reinforcement, respectively. All reinforcement is embedded in concrete of the kind in which the aggregate of the concrete comprises particulate expanded polystyrene. In one embodiment disclosed in PCT/NO2016/050083, the aggregate of the concrete consists exclusively of particulate expanded polystyrene.
In what follows, concrete of the kind in which the aggregate of the concrete comprises or consists of particulate expanded polystyrene will also be referred to as EPS concrete. The use of EPS concrete as a material in addition to reinforcement has the effect of the plate element achieving a density in the order of 20-25 % of that of a corresponding slab made from solid, reinforced concrete, and in the order of 40-50 % of that of a corresponding slab made as a filigree slab. The reduced density will, in turn, have the positive effect of allowing the amount of reinforcement to be reduced in relation to that necessary for a corresponding slab of a higher density. A reduced amount of reinforcement will, in turn, have a positive effect on the overall weight of the structure.
The lattice girders embedded in the EPS concrete are stabilized against buckling on compressive stress by both the EPS concrete and the upper and lower mesh reinforcements. It is therefore important that each of these is firmly fixed to the lattice girders. Adhesion between the EPS concrete and the reinforcement ensures exploitation of the tensile capacity of the reinforcement.
The two-dimensional lattice girder may be formed of wire and comprises a lower chord, an upper chord and diagonal members extending in zigzag between the lower chord and the upper chord between the first end portions. The purpose of the diagonal members is to absorb shear forces.
In one embodiment, the lattice girder may extend in three-dimensions between the first end portions. This has the effect of increasing the buckling capacity in relation to that of a two-dimensional lattice girder, among other things.
Such a three-dimensional lattice girder may be formed of wire and comprises a lower chord, an upper chord and diagonal members extending in zigzag between the lower chord and the upper chord, at least one of the upper chord and the lower chord comprising two spaced-apart wires. Seen from an end portion, the at least two lattice girders that are arranged in a spaced-apart manner may thus exhibit a V-shape or a A-shape, or a combination thereof.
To provide a sturdy joint between the lattice girder and the upper mesh reinforcement and the lower mesh reinforcement, the joint of the reinforcement may be provided by means of welding.
The application PCT/NO2016/050083 further discloses a method of producing the plate-shaped slab element, wherein the method includes: providing a formwork; positioning at least two lattice girders with upper portions and lower portions substantially in parallel, and joining a mesh reinforcement to each of the upper and lower portions of the lattice girders in order to produce a complete reinforcement; placing the complete reinforcement in the desired position in the formwork; and preparing a homogenous concrete mass in which the aggregate of the concrete comprises particulate expanded polystyrene, and filling the concrete into the formwork so that the complete reinforcement is embedded in the homogenous concrete mass.
The plate-shaped slab element disclosed in PCT/NO2016/050083 is particularly suitable for use as the first building element for carrying the first joint element, and the second building element for carrying the second joint element both of which form part of the connection means according to the present invention.
In one embodiment of the present invention, a concrete slab element is provided with at least two spaced-apart three-dimensional lattice girders connected at an upper portion and at a lower portion to an upper mesh reinforcement and a lower mesh reinforcement.
The concrete wall element may be provided with a similar reinforcement arrangement, or by means of said at least two spaced-apart two-dimensional lattice girders connected at an upper portion and at a lower portion to an upper mesh reinforcement and a lower mesh reinforcement.
As mentioned above, the first joint element and the second joint element are fixed, by means of welds to end portions of the reinforcement of first building element and second building element, respectively. By doing so, there is provided a rigid connection capable of transferring bending moment. However, it is also conceivable to fix the joint elements by means of mechanical connection means, such as bolts, wires etc., adhesive means or a combination of two or more of those.
In one embodiment, the end portions of each lattice girder are provided with a first joint element or a second joint element.
However, the first and second joint elements may alternatively be fixed to the first and second building elements by means of for example rods or angle steel extending from the joint elements into the building elements. Such rods or angle steel must be designed to resist forces acting on the joint elements. Said rods or angle steel and/or the joint elements themselves must be secured in correct position prior to pouring concrete into the formwork, for example by connecting the joint element to the formwork.
The second building element, for example a wall element, may in one embodiment be provided with at least one element bore extending through side faces, i.e. the thickness, thereof and through the second joint element. In such an embodiment a corresponding member bore may be provided through a portion of the elongate member. The bores are arranged at positions allowing alignment of the bores after the elongate member has been slid into the cavity of the second joint element so that a locking device for preventing movement of the elongate member out of the cavity, may be inserted into the bores. The locking device may typically be a rod, for example a bolt. Such a bolt may be provided with a nut to prevent movement of the bolt out of the bore.
The bores in the second building element, the second joint element and the elongate member may in accordance with the embodiment above thus be premade and arranged at positions allowing alignment of the bores in the position of use. Alternatively, the bore for receiving the locking device may be made by drilling through said elements and member after installation.
According to a second aspect of the present invention, there is provided a building comprising the connecting means according to first aspect of the invention.
According to a third aspect of the present invention, there is provided a method for connecting building elements by means of the connecting means according to the first aspect of the invention, wherein the method comprises:
- mutually aligning the at least one first joint element and the second joint element;
- sliding the elongate member into engagement with the first joint element and the second joint element.
In an erection situation were the first building element is for example a floor element to be carried on top of the second building element, such as a wall element, the at least one first joint element and second joint element may be mutually aligned so that they are brought into a mutually correct position for receiving the elongate member. Thereafter, the elongate member may first be slid into engagement with the first joint element(s) and further into engagement with the second joint element.
Alternatively, the elongate member may first be inserted into engagement with the second joint element so that it protrudes upwardly therefrom. Thereafter, the first joint element of the first building element may be slid into engagement with the elongate member and lowered until the first building element is supported on top of the second building element.
If a second building element, for example a wall element, is alternatively or additionally required on top of the first building element (as will be the case in a multi storage building wherein a floor element provides support for a wall element), the elongate member may have a length providing an upward protrusion from a top surface of the first building element. The second joint element of the further second building element (for example a wall element or a column) may then be slid into engagement with the protruding elongate member.
In order to lock a second building element being supported on top of the first building element, a locking device may be inserted through a bore extending therethrough, through the second joint and through the elongate member, as discussed above.
Provided correct arrangement of the first joint element and second joint element in the first and second building element, respectively, the connecting means will assure correct mutual position of the building elements and also a rigid connection capable of transferring bending moments. Further, a building structure assembled by means of the connecting means according to the present invention, may easily be disassembled. Such a possibility of disassembly is particularly useful for temporary building structures.
In the following is described examples of preferred embodiments illustrated in the accompanying drawings, wherein:
Fig. 1 shows a perspective view of spaced apart items of the connection means;
Fig. 2 shows in a larger scale a first joint element connected to an end portion of a first building element shown to the right in fig. 1;
Fig. 3 shows in a larger scale a second joint element connected to an uppermost end portion of a lowermost second building element shown in fig. 1 ;
Fig. 4 shows two first building elements aligned and abutting each other on top of a second building element, and further an elongate member prior to interlocking the first joint elements of the first building elements with the second joint element of the second building element;
Fig. 5a shows a second building element being lowered on top of the first building elements shown in fig. 4, but after the elongate member has been inserted;
Fig. 5b shows in larger scale a top view of the first building elements shown in fig. 5a, after installing the elongate member;
Fig. 5c shows in larger scale an alternative embodiment of the connecting means shown in fig. 5b;
Fig. 6 shows the building structure after the second building element shown in fig. 5a has been connected;
Fig. 7 shows a portion of a building structure after assembly;
Fig. 8a shows a typical plate-shaped concrete slab element comprising, at opposite end portions, first joint elements according to the present invention, the concrete slab is viewed from a top side in which lattice girders are shown;
Fig. 8b shows the slab element of fig. 8a in a sectional view through l-l of fig. 8a, and an additional wall element supporting the slab element;
Fig. 9a shows a section through the line ll-ll of fig. 8a on a larger scale;
Fig. 9b shows an alternative embodiment of the lattice girder shown in fig. 9a;
Fig. 10a shows an alternative embodiment of a first joint element and a second joint element connected to an end portion of a first building element and a second building element, respectively, prior to connecting the joint elements, the second building elements being an outer wall;
Fig. 10b shows in larger scale the joint elements in fig. 10a connected together;
Fig. 11a shows in larger scale similar joint elements as shown in fig. 10a, but where the second building element is an inner wall;
Fig. 11b shows the joint elements in fig. 11a connected together;
Figs. 12a 12b show an alternative embodiment of the joint elements in figures 10a and 10b;
Figs. 12c shows an alternative embodiment of the joint elements in fig. 11 b;
Fig. 13a shows in larger scale a cut through A-A in fig. 10a;
Fig. 13b shows in larger scale a cut through B-B in fig. 10a;
Fig. 13c shows in larger scale a cut through C-C in fig. 10a;
Fig. 14a shows the first joint elements and second joint elements utilized in the building elements shown in fig. 11a;
Fig. 14b shows the first joint elements and second joint elements utilized in the building elements shown in fig. 11 b;
Fig 14c shows a cut through D-D in fig. 14b, i.e. the first joint elements seen from above; and
Fig. 15 shows a principle, perspective view of a first building element connected between two second building elements similar to the embodiment shown in fig. 10b.
Positional specifications, such as over, under, upper, lower, top, bottom, right and left, refer to the positions that are shown in the figures.
In the figures, same or corresponding elements are indicated by same reference numerals. For clarity, some elements may in some of the figures be without reference numerals.
For illustrative reasons, the relative proportions of some of the elements may be somewhat distorted.
In the figures, the reference numeral 1 indicates a building structure connecting means. The connecting means 1 is configured for connecting an end portion 3 of at least one first building element 5 to an end portion 7 of at least one second building element 9. In the figures, the first building elements 5 are shown as plate-shaped concrete slabs 5, and the second building elements 9 are shown as plate-shaped concrete wall elements 9. Each slab 5 and wall element 9 is provided with reinforcement R as will be discussed below.
The concrete slab has a length L5, a width W5 and a thickness T5. Similarly, the concrete wall element 9 has a length L9, a width W9 and a thickness T9. It should be noted that in figures 1 to 7 and figures 10a to 13c only a portion of each slab 5 and wall element 9 is shown. Normally, the lengths L5 and L9 are larger than the width W5 and W9 of the slab 5 and wall element 9, respectively, as shown in fig. 8a.
It should be noted that the width W5 of the slab 5 may be different from the width W9 of the wall element 9, although shown identical in figures 1, 4, 5a and 6.
In a first embodiment shown in figures 1 to 8b, the connecting means 1 comprises a first joint element 11 integrally connected to the end portion 3 of the concrete slab 5, i.e. the first joint element constitute a part of the end portion of the concrete slab 5. The first joint element 11 has a length substantially corresponding to the thickness T5 of the concrete slab 5, i.e. a longitudinal axis of the first joint element 11 extends between a top surface and a bottom surface of the concrete slab 5.
The connecting means 1 further comprises a second joint element 13 integrally connected to the end portion 7 of the wall element 9, i.e. the second joint element 13 constitute a part of the end portion 7 of the wall element 9. The second joint element 13 has in the first embodiment a longitudinal axis running in parallel with a longitudinal axis extending between the end portions 7 of the second building elements 9.
In figures 1 to 5a the concrete itself is shown transparent, but the reinforcement is shown.
In the first embodiment, the connecting means 1 further comprises an elongate member 20 for interlocking with at least one, i.e. one or two, first joint element 11 and at least one, i.e. one or two, second joint element 13. The elongate member 20 has a length exceeding the length of the first joint element 11 , i.e. exceeding the thickness T5 of the slab 5.
In the first embodiment shown in figures 1 , 4, 5a and 5b, the elongate member 20 is a girder 20 having an H-girder section comprising girder flanges 22 spaced apart by a girder web 24 as shown in fig. 5b. As an alternative to an H-girder section shown in fig. 5b, the elongate member 20 may have an I-girder section as shown in larger scale in fig. 5c.
The first joint element 11 is provided with a recess 111 for receiving a portion of one of the girder flanges 22 of the girder 20, and a slot 113 for receiving a portion of the girder web 24. The recess 111 and the slot 113 are open-ended, so that the girder 20 may slide with respect to the first joint element 11. See for example fig. 4.
An advantage with an elongate member 20 having H- or I-girder section is that the elongate member 20 may connect two first building elements 5 aligned and abutting each other on top of a second building element 9.
The first joint element 11 is in the first embodiment shown in fig. 2, further provided with a top flange 115 and a bottom flange 117 connected, for example by means of a weld, at end portions of the first joint element 11. The top flange 115 and bottom flange 117 extend in parallel with a top and bottom surface, respectively, of the slab element 5. The primary purpose of the flanges 115, 117 is to provide a rigid connection between the first joint element 11 and the slab 5. Rods 119 are connected to inner end portions of the flanges 115, 117 by means of a weld. One purpose of the rods 119 is to serve as stiffeners for keeping the flanges 115, 117 in correct position with respect to the surfaces of the concrete slab 5. Another purpose of the rods 119 is to serve as a binding agent between the concrete and the first joint element 11 , thereby reducing the risk of pulling out the first joint element 11 when subject to, for example, bending moment.
The flanges 115, 117 may further be provided with a plurality of friction- or engagement increasing means, such as protrusions (not shown) extending into the concrete slab element 5.
In a situation where only one first building element 5 is to be connected to a second building element, for example when a slab 5 is to be connected to an outer wall element 9 of a building, the H-or I-girder 20 may be replaced by for example an RHS-girder (RHS- Rectangular Hollow Section). The slot 113 in the first joint element may then be superfluous.
The second joint element 13 comprises in the embodiment shown for example in fig. 3, a cavity 131 for receiving and supporting an end portion of the elongate member 20. In the embodiment shown, the cavity 131 is defined by a rectangular hollow section 133 configured to provide support for the girder flanges 22. A longitudinal axis of the rectangular hollow section 133 runs in parallel with a longitudinal axis extending between end portions 7 of the second building element 9. At an outer end portion, the rectangular hollow section 133 is provided with RHS flanges 135 extending rectangularly outwards from the rectangular hollow section 133 so that the RHS flanges 135 is planar with an end surface 7 of the second building element 9. The purpose of the RHS flanges 135 is similar to that of the flanges 115, 117 of the first building element 5.
The second joint element 13 may, as mentioned above, be provided with a bottom plate (not shown) for supporting an end face of the elongate member 20, and for preventing flow of uncured concrete into the cavity during manufacturing of the second building element 9.
In order to transfer forces from the concrete reinforcement R to the first joint element 11 and the second joint element 13, said joint elements 11, 13 are in the embodiment shown connected to the reinforcement R for example my means of welds.
Fig. 1 shows an "exploded" view of the first embodiment of the connecting means 1 according to the present invention wherein two concrete slabs 5 are to be supported by a wall element 9. After installation of the two concrete slabs 5, a further wall element 9 is to be put on top thereof. To provide a rigid connection capable of transferring bending moment, the elements 5, 9 are interconnected by means of the H-girder 20.
The H- or I-girder 20 may be connected in at least three alternative steps.
In a first alternative, after the slabs 5 has been arranged on top of the lower wall element 9, the H-girder 20 is slid into engagement with the recesses 111 and slots 113 of the first joint elements 11 of the slabs 5, and then into the cavity 131 of the lower second joint element 13. Thereafter, upper wall element 9 is lowered onto the slabs 5 such that the H- or I-girder 20 slides into the cavity 131 in the second joint element 13. The first alternative is indicated in figures 4 and 5a.
In a second alternative, the H- or I-girder 20 may be inserted into the cavity 131 of the lower second joint element 13 prior to installing the slabs 5 onto the wall element 9. Then, each of the slabs 5 is successively connected to the H- or I-girder 20 by “threading" the first joint element 11 into a top portion of the H- or I-girder 20 and then slide the slab 5 until it abuts the top portion 7 of the lower wall element 11. Thereafter, the upper wall element 9 is lowered onto the slabs 5 such that the H- or I-girder 20 slides into the cavity 131 in the second joint element 13.
In a third alternative, the H- or I-girder 20 may be inserted into the cavity 131 of the second joint element 13 of the upper wall portion 9 and connected thereto. The upper wall portion 9 is then lowered such that the H- or I-girder 20 slides simultaneously into engagement with the first joint ele ments 11 of the slabs 5 resting on the lower wall element 9 and further into engagement with the cavity 131 of the lower second joint element 13.
Independently of the alternatives described above, the upper and lower wall elements 9 may be prevented from vertical movement by means of a locking device. In the figures, the locking device is shown as a bolt 26 inserted through a bore 28 running through the wall element 9, the second joint element 13 and a bore 29 running through the H- or I-girder 20, as shown in principle in figures 6 and 7.
In figures 1 to 5a and in fig. 7, the slabs 5 and walls 7 are for illustrative purposes shown as transparent concrete elements with reinforcement generally denoted R.
Fig. 5b and fig. 5c show an elongate member 20 in the form of an H-girder 20 and an I-girder 20, respectively. The web 24 of the I-girder 20 shown in fig. 5c is supported by means of angle irons 30 (four shown) bolted to a portion of the first joint element 11.
Figures 8a, 8b, 9a and 9b show principle drawings of a suitable reinforcement. Reinforcement in the wall element 9 is not shown in fig. 8b.
Figures 8a, 8b and 9a show a lattice girder 140 extending in zigzag both in the width and in the height between the first end portions 3 of the slab 5. For clarity, a reinforcement in the wall portion is not shown in fig. 8b.
An upper mesh reinforcement 142, as best seen in figures 9a and 9b, is fixed by means of weld connections to an upper portion 140' of the lattice girder 140. Correspondingly, a lower mesh reinforcement 144 is fixed by means of weld connections to a lower portion 140" of the lattice girder 140.
The lattice girder 140 comprises a lower chord 146, an upper chord 148 and diagonal members 150 extending in zigzag between the lower chord 146 and the upper chord 148 along the length L5 of the slab element 5.
In fig. 9a, the lattice girder 140 is shown in a first, three-dimensional variant. The lattice girders 140 are shown arranged alternatingly in a A-shape and a V-shape.
The lattice girder 140 in a A-shape (three shown in fig. 9a) is provided, in its lower portion 140", with two lower chords 146 arranged in parallel and in a spaced-apart manner. In its upper portion 140', the lattice girder 140 is provided with one upper chord 148. The diagonal members 150 are "wrapped" in zigzag around the longitudinal axes of the chords 146, 148.
The lattice girder 140 in a V-shape (two shown in fig. 9a) is provided, in its lower portion 140", with one lower chord 146. In its upper portion 140', the lattice girder 140 is provided with two upper chords 148 arranged in parallel and in a spaced-apart manner. Here, too, the diagonal members 150 are wrapped in zigzag around the longitudinal axes of the chords 146, 148.
In fig. 9b, the lattice girder 140 is shown in a second two-dimensional variant, in which the lower chord 146 consists of one wire, and the upper chord 148 consists of one wire. The diagonal members 150 are wrapped in zigzags along the longitudinal axes of the chords 146, 148.
s The wall elements 9 may be provided with a similar arrangement of the reinforcement.
In one embodiment, the concrete slab 5 is provided with a reinforcement arrangement shown in fig.
9a, while the wall element 9 is provided with a reinforcement arrangement as shown in fig. 9b.
In figures 1 to 7 only one lattice girder 140 is indicated in each slab 5, while two lattice girders of the type indicated in fig. 9b is shown. This for clarity reasons. However, the slab 5 and the wall ia element 9 are provided with a plurality of lattice girders 140, as best seen in figures 8a, 9a and 9b.
Turning now to figures 10a to 15 showing an alternative embodiment of the first embodiment of the connecting means 1 shown in figures 1 to 7 and also indicated in figures 8a and 8b. This alternative embodiment will be denoted the second embodiment.
The main difference between the first embodiment and the second embodiment shown in figures is 10a to 15 is that while the elongate member 20 of the first embodiment is in the form of a member, such as an H- or I-girder, having a length exceeding the length of the first joint element 11 , the elongate member 20 of the second embodiment is in the form of a bolt or a plurality of bolts 20 configured for slidable engagement with at least one of for example the first joint element 11 and the second joint element 13.
2o The first joint element 11 and the second joint element 13 are typically made from metal, such as steel.
As shown in the second embodiment, the first joint element 11 comprises a box section 111 integrated in and forming part of the end portion 3 of the first building element 5, see for example fig.
13c and fig. 15. The box section 111 is provided with apertures 112 for receiving elongate mem-25 bers 20 in the form of bolts 20.
The second joint element 13 shown in the second embodiment comprises a plate member 132 forming part of the end portion 7 of the second building element 9. The plate member 132 is in the embodiment shown provided with apertures 112<'>(see fig. 14a) for mating with the apertures 112 in the box section 111. However, in an alternative embodiment (not shown) the plate member may be 30 provided with bolts fixedly connected, typically by means of a weld, to an outer portion of the plate member 132 so that the bolts protrude from said portion and can be slid into the apertures 112 of the box section 111.
Fig. 10a shows the first building element 5 in the form of a reinforced concrete slab 5 prior to assembly with two second building elements 9 in the form of outer wall elements 9. One of the outer wall elements 9 is going to form a support for the slab 5, while the other one is going to be supported by the slab 5. The wall elements 9 are made from reinforced concrete. In the embodiment shown, the reinforcement of the slab 5 and wall elements 9 are similar to that shown in fig. 9b.
The lowermost of the two wall elements 9 shown, is to be supported by a foundation F known per se provided with bolts 20F protruding from a top portion of the foundation F.
The box section 111 of the first joint element 11 and the plate member 132 of the second joint element 13 are further provided with protruding members 120 extending into the concrete of the slab 5 and wall elements 9, respectively.
In the embodiment shown, the protruding members 120 are in the form of angular steel members 120 fixedly connected, for example by means of a weld, to each of the box section 111 and the plate member 132. The protruding members 120 are connected to the box section 111 of the first joint element 11 and the plate member 132 of the second joint element 13 prior to arranging the first joint element 11 and second joint element 13 in a formwork. The protruding members 120 can therefore be connected to a portion of the reinforcement 146, 148, for example by a wire or preferably by means of a weld. The advantage of welding the protruding members 120 to the reinforcement 146, 148 is that forces carried by the reinforcement 146, 148, 150 is transferred directly to the angular steel elements 120 and to the box section 111 of first joint element 11 and the plate member 132 of second joint element 13, respectively. When connected, the connection will be capable of transferring bending moments between one or more wall element(s) 9 and one or more slab element(s) 5.
Such a solution is of particular importance in the present invention since the aggregate of the concrete comprises or consists of particulate expanded polystyrene, i.e. since the slab 5 and wall element 9 are made from EPS concrete, wherein tension and compression forces are carried substantially by the reinforcement R only, and the EPS concrete provides support for reinforcement being in compression and thus prevents buckling of the compression reinforcement.
It should be noted that the protruding members 120 may as an alternative to angular steel, be made from for example steel rods. However, protruding members 120 made from angular steel are preferred as such angular steel members 120 will provide a connection being much stiffer than a connection made from steel rods. A stiff connection is particularly desirable when there is a desire for a connection capable of transferring bending moments between one or more wall element(s) 9 and one or more slab element(s) 5.
In the embodiment shown in figures 10a and 10b, an end portion of the box section 111 of the first joint element 11 forming part of an end face of the slab end portion 3, is provided with a detachable end plate 111<'>. The end plate 111<'>is shown detached in fig. 10a, and connected to the box section 111 in fig. 10b. The purpose of the detachable end plate 11 Γ is to get access to an inside of the box section 111 such that nuts can be connected to bolts 20 extending from the second joint elements 13 and slid through the apertures 112 in the box section 111 during erection of a building structure comprising the connection means 1. Similarly, the detachable end plate 111<'>makes it possible to get access to the joint if there is a need for dismantling a building structure comprising the connecting means 1. The first joint element 11 may be provided with further stiffening devices, such as for example stiffening ribs connected to one or more of the walls and possibly also to the detachable end plate 111<'>, to increase the load bearing capacity of the first joint element 11.
Fig. 13b is a view from section B-B in fig. 10a and shows four end plate supports 111<">for supporting the end plate 111<'>connected by means of screws (not shown). A detached end plate 111<'>is indicated to the right of the box section 111 in fig. 10a.
In fig. 10a, the bolts 20 constituting the elongate member for slidable engaging the first joint element 11 and the second joint element 13, are pre-installed through the apertures 112<'>in the plate member 132 of the second joint element 13 during manufacturing of the wall elements 9, i.e. prior to pouring concrete into a formwork.
A lower end portion of the wall element 9 below the slab 5 is provided with cut-outs 9<'>indicated by dotted lines. The purpose of the cut-outs 9<'>is to get access for connecting nuts to the bolts 20F protruding from the foundation F. After tightening of the bolt and nut connection, the cut-outs 9<'>may be sealed by a suitable sealing means.
Fig. 10b shows in a larger scale the same elements as shown in fig. 10a after assembling a building structure by means of the connecting means 1.
Fig. 11a shows the first building element in the form of two reinforced concrete slabs 5 prior to assembly with second building elements in the form of inner wall elements 9. The lower inner wall element 9 is going to form a support for the slabs 5, while the upper wall element 9 is going to be supported by the slabs 5.
The building structure connecting means 1 shown in fig. 11a has several features in common with that shown in fig. 10a. For example, the angular steel 120 protruding from each of the the box sections 111 and the plate members 132, are connected thereto and to the reinforcement 146, 148 in the same way as described above.
The box section 111 of the first joint element 11 is provided with a partly open top portion instead of the detachable end plate 111<'>shown in fig. 10a. The partly open top portion which is best seen in figures 14a and 14c, is denoted by reference numeral 114. The purpose of the partly open top portion 114 of the box section 111 is to get access to the internal portions of the two box sections 111 for connecting nuts to the bolts 20 extending into the box sections 11 from the lower wall element 9, and to the "horizontal" bolts shown. The partly open top portion 114 is available only prior to lowering the upper wall element 9 onto the slabs 5.
The top portion of the box section 111 is provided with bolt-supporting lips 20<'>(four shown in fig.
14c) for supporting bolts (not shown) to be slid into engagement with the plate member 132 of the upper wall element 9 which is to be supported by the slab 5.
s The bolts 20 are connected to the supporting lips 20<'>typically by means of threaded connections.
The lower wall element 9 shown in fig. 11a is in the embodiment shown identical to the lower wall element 9 shown in fig. 10a.
The lower end portion of the wall element 9 above the slab 5 is provided with a cut-out 9<'>similar to the cut-out shown in fig. 10a for the lower end portion of the wall element 9 below the slab 5. The ia purpose of the cut-outs 9<'>is to get access for connecting nuts to the bolts 20 protruding from the supporting lips 20<'>of the box sections 111 of the first joint elements 11. After tightening of the bolt and nut connection, the cut-outs 9<'>will typically be sealed with a suitable sealing means.
It should be noted that the lower end portion of the wall element 9 above the slab 5, as shown in fig. 10a, may be similar to that shown in fig. 11a, i.e. the bolts 20 may be slid from an inside of the is box section 111 shown in fig. 10a and into the apertures 112<'>(see fig. 14a) of the plate member 132 of the upper wall element 9 being above the slab 5.
Fig. 11b shows the same elements as shown in fig. 11a after assembling a building structure by means of the connecting means 1.
From the above, a person skilled in the art will appreciate that the assembling procedure for the 2o building elements 5, 9 shown in figures 10a and 10b, is different from the assembling procedure for the building elements 5, 9 shown in figures 11a and 11b.
In the embodiment shown in figures 10a and 10b, the internal portion of the box section 111 of the first joint element 11 is accessible at all times until the detachable end plate 111<'>is fixed to the box section 111. Thus, the tightening of the bolts by means of the nuts, may, but does not have to, be 25 carried out after the upper wall element 9 rests on the slab 5 which rests on the lower wall element 9.
In the embodiment shown in figures 11 a and 11b, the internal portion of the box section 111 of the first joint element 11 is accessible only until the upper wall element 9 is lowered onto the slabs 5 so that the end portion 7 of the upper wall element 9 covers the partly open top portion 114 of the box 30 section 111. Thus, the bolts 20 connecting the slabs 5 to the lower wall element 9 and the end portions of each of the box sections 111 (the bolts 20 arranged horizontally) must be provided with nuts and tightened prior to lowering the upper wall element 9 onto the slabs 5. Thereafter, the bolts 20 for connecting the upper wall element 9 to the slabs 5 must be provided with nuts, and tightened.
It should be noted that In some embodiments, the horizontal bolts 20 (see fig. 11b) connecting the end portions of each of the box sections 111, may be superfluous. Alternatively, said horizontal bolts 20 may be replaced by suitable engagement means, such as for example hooking devices arranged for interconnecting with each other when sliding the end portion of one of the slabs 5 provided with a hooking device, with respect to the end portion of the other of the slabs 5 also provided with a hooking device.
Turning now to figures 12a to 12c showing inter alia an alternative embodiment of the elongate members 20, i.e. the bolts, shown in figures 10a to 11b.
In figures 12a to 12c, each of the elongate members 20 having a longitudinal axis extending vertically, has a length exceeding the length of the first joint element 11. By the term "length” of the first joint element 11 is meant the height of the box section 111 which substantially corresponds to the thickness of the slab 5.
The elongate members 20 shown in figures 12a to 12c are shown as bolts 20 extending from the plate member 132 of the lower wall element 9 in the same way as described above. Due to their length exceeding the length of the box section 111 of the slab 5 (figs. 12a and 12b) or slabs (fig.
12c), each one of the elongate members or bolts 20 will provide a continuous connection between both of the wall elements 9 and the slab element(s) 5. Thus, the bolts may also transfer vertical loads between the upper and lower wall elements 9.
The elongate members 20 will thus provide a slidable engagement with at least one of the first joint element and the second joint element such that relative horizontal movement between the first joint element 11 and the second joint element 13 is prevented even before the bolt 20 is provided with a nut.
The lower end portion of the wall element 9 above the slab(s) 5 is provided with a cut-out 9<'>similar to the cut-out 9<'>shown in fig. 11a to allow engagement of a nut to the end portion of the bolt 20.
The elongate members or bolts 20 shown in figures 12a and 12b may make the detachable plate 11 Γ superfluous. The box section 111 may thus be provided with a welded end portion. As no access to the internal of the box section 111 is required in this embodiment, further loadbearing means, such as for example one or more stiffening ribs, may be provided in the internal portions of the box section 111.
If the horizontal bolts 20 disclosed in fig. 11 b are superfluous, or if said horizontal bolts 20 are replaced by suitable engagement means, as discussed above, the partly open top portion 114 of the box section 111 shown for example in figs. 11a, 11b and 14c, may be replaced with a solid portion provided with apertures for the bolts 20 only. Bolt guiding means, such as for example tubes (not shown) may extend between the apertures 112 of the box sections 111.
Fig. 13a shows a cut through A-A in fig. 10a. Reinforcement 146, 148 is welded (not shown) to the upper and lower protruding members 120. A diagonal reinforcement member 150 extends between the protruding members 120, and a portion of the diagonal reinforcement member 150 may be welded to the protruding members 120. The first joint element 11 is shown by means of dashed lines.
Fig. 13b shows the first joint element 11 and the end portion 3 the first building element seen from B-B in fig. 10a.
Fig. 13c shows a cut through C-C in fig. 10a. Reinforcement 146, 148 is welded (not shown) to the protruding members 120 and extends there between.
Figs. 14a, 14b show only the first joint elements 11 and second joint elements 13 utilized in the building elements shown in figures 11a and 11b, respectively.
Fig. 15 shows a principle, perspective view of a first building element 5 connected between two second building elements 9 similar to the embodiment shown in fig. 10b. The building elements 5, 9 are shown transparent. The bolts 20 extending from the lower second building element 9 into the box section 111 of the first building element 5 have been provided with nuts, while nuts for the bolts 20 extending downwardly from the upper second building element 9 are shown prior to engagement with the bolts 20. Reinforcement R is welded (not shown) to the protruding members which in the shown embodiment are in the form of angle steel.
It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. Use of the verb "comprise" and its conjugations does not exclude the presence of elements or steps other than those stated in a claim. The article "a" or "an" preceding an element does not exclude the presence of a plurality of such elements.
The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.