EP4056779B1

EP4056779B1 - Connection arrangement

Info

Publication number: EP4056779B1
Application number: EP22158166.3A
Authority: EP
Inventors: Esko Mäkinen
Original assignee: Anstar Oy
Current assignee: Anstar Oy
Priority date: 2021-03-11
Filing date: 2022-02-23
Publication date: 2024-04-10
Anticipated expiration: 2042-02-23
Also published as: FI20215263A1; EP4056779A1; PL4056779T3; EP4056779C0; FI130308B

Description

This invention relates to a connection arrangement for connecting a vertical element, such as a column or a wall element, and a horizontal element, such as a beam, to each other according to claim 1. The invention also relates to a connection comprising a vertical element, such as a column or a wall element, and a beam.
The beam-column connections of concrete-structured frames have been made already for decades by a special hidden bracket technique. By means of the hidden bracket, the connection can be hidden inside the beam and the column, and thus will not hinder the use of the building. Hidden brackets have established themselves as part of the concrete structure element system. The hidden brackets were initially developed for concrete elements only, but their use has also spread to the connections of composite column-composite beam frames, and also to the so-called mixed frame connections in which the material of the beam and the column varies according to building. The significant product development of brackets took place in the 1990s and in the beginning of 2000s, after which they have not much been improved, although frame construction has advanced.
The first hidden bracket achieving a wide market position was based on patent FI83358 which has been utilized in hidden bracket applications of concrete structures. Another hidden bracket which has achieved commercial success was described in patent EP1334244 . A bracket described in patent FI89193 is based on a completely different configuration in which a tongue part of the bracket is inserted from the beam into the column in the installation situation. This bracket did not solve the problems caused by torsional moment of the beam either, and torsional moment was not allowed for the practical application of the bracket. A bracket described in patent FI72369 only transfers the vertical load of the beam, not the torsional moment. There are also other patents relating to hidden brackets, but they have had little success in commercial applications. Document DE4313895 discloses a bracket comprising all the features of the preamble of claim 1.
As a structure, the hidden bracket is very challenging, because it must transfer very high loads from the beam to the column in a very small space. The bracket connection transfers a vertical load of the beam to the column. This load acts in the different construction stages at different magnitudes. The load acts in general in the downward direction but in the installation situation it may momentarily be also directed upwards. The bracket connection is also subject to a horizontal load in the longitudinal direction of the beam, which horizontal load may act in opposite directions. Additionally, a torsional moment tending to rotate the beam acts on the bracket connection. The bending moment of the end of the beam is not in general transferred by hidden brackets, as it constitutes a very challenging structure for which a well-functioning application has not yet been developed.
In the hidden bracket structure there are in general three parts by means of which the connection between the beam and the column is formed. The column in general comprises a column part fastened to the column, which column part transfers and fixes the forces from the beam to the column. A beam part is fastened to the beam, which beam part transfers the loads of the beam to a tongue part of the column part. The tongue part forms the most challenging structure of the connection, because it is subject to the highest loads and it is required to have many functional properties especially in the installation stage of the connection.
There are different load situations acting on the connection during construction and use, such as installation, use, accident and fire situations. The requirements posed by different situations differ from each other and the requirements must be met in all situations. Especially the beam installation situation is very challenging for the structure of the hidden bracket, because in the installation situation, all concrete pouring for the structures has not yet been performed and functioning of the connection therefore differs significantly from the other design situations.
After the beginning of 2000s, the frame systems of buildings have developed considerably and the trend is more and more towards the use of so-called mixed frames. This sets new requirements for the bracket structure, as the bracket must be suitable for frame structures in the connections of which the material of the beam and the column may change even within the building and even at different ends of the same beam. The hidden bracket system must therefore adapt to the requirements of the building frame. Therefore, it has become a general requirement that the beam part of the bracket connection must fit a concrete, composite and steel column without the structure of the beam part being changed. This requirement is not met by the current commercial bracket systems, as they are frame material specific. In the known configurations, the connections must be designed according to the material of the beam or the column and the material of the frame structure cannot be changed without changing the connection structure of the beam or the column. In one embodiment of this invention, a connection arrangement is presented, by means of which connection arrangement a concrete beam or a composite beam may be connected to a composite column or a steel column using the same connection arrangement. The frame material of the building thus no longer poses an obstacle to the use and fitting of the bracket connection together with different frame structure materials.
Below, the functional properties required of the bracket structure due to the loads coming from the beam will be examined. The vertical load of the beam is transferred from an end plate of the beam part by the tongue part of the bracket, wherein the surface of the column is provided with a metallic projection, generally a rectangular-shaped plate, over which the bracket parts of the end plate of the beam are supported. This structure functions in general quite well and transfers the vertical loads reliably to the column. In the known bracket applications the beam is always installed by lowering from above onto the tongue part of the bracket, and the beam is not fastened in any way to the tongue part, but the weight of the beam and the projection parts of the tongue part hold the beam in its place. In new frame structures the continuity of the beams forms a situation where, in the installation situation, the end of the beam is also subject to lifting forces. The lifting force has in general been removed by installation support. In one embodiment of this invention, locking of the bracket also for the force lifting the end of the beam is introduced, whereby the installation support is not needed.
Horizontal forces of the beam are transferred by the projections of the tongue part of the bracket, behind which projections the abutment parts of the beam part are supported. These abutment parts function generally well, but they all have one problem: the beam must move to the extent of the tolerance clearance of the connection before the abutment parts are supported to each other and begin to transfer the horizontal load. In one embodiment of this invention, locking of the bracket immoveable for forces in the longitudinal direction of the beam is introduced. The locking is also used for transferring the lifting force.
The transfer of torsional moment of the beam to the column is the most challenging property of the hidden bracket connection. In the installation situation of the bracket connection there must be an installation clearance between the beam part, the column part and the tongue part. The installation clearance is required because the abutment surfaces of the beam part must fit the tongue part as the beam is installed from above onto the support surfaces of the tongue part. The beams, the columns and the bracket parts generally have small manufacturing variations, whereby the parts are not fully in the designed dimensions. Therefore, between the abutment surfaces of the connection, there must be an installation clearance compensating for these variations and allowing the connection to be installed.
However, the torsional moment of the beam is transferred by these very same abutment connection parts, requiring that the connection parts should be in contact with each other. If some clearance remains in the connection, it may still transfer the torsion, but it causes at the same time harmful rotation in the beam, which is often not allowable or desirable. The requirements are thus mutually exclusive, because transfer of the torsional moment requires contact between the connection parts, while installation of the connection requires a clearance between the same parts. In one embodiment of this invention, a solution is presented, by which solution the clearance for the abutment parts of the connection and the transfer of the torsional moment are solved in such a way that there is a sufficient installation clearance in the connection in the installation situation, but at the end of installation the connection parts come into contact against each other as needed for transferring the torsional moment, such that a small clearance is provided between them. Thereby no harmful rotation is caused in the connection in the end situation, and it is also locked for the torsional moment.
The transfer of all of these three forces has not been solved in the known brackets in the same connection. If torsional moment is not allowed for the bracket connection during installation of the beam, or the bracket connection rotates too much due to the torsional moment because of the clearance of the connection, the beams must be installed by using temporary installation support. The installation support is an expensive operation which slows down the construction and thus causes additional costs. Constructors want to remove this additional cost. In the embodiments of this invention, a bracket structure is formed, by which bracket structure the beam-column connection may be made with a hidden bracket which does not need installation support removing the torsional moment and at the same time it transfers the torsional moment without harmful rotation of the beam.
Below, the ways in which the transfer of torsion in the connection has been solved in the known brackets will be examined. Patent FI83358 discloses a rectangular-shaped tongue part, wherein between the tongue part and a slot of the end plate of the beam part there are vertical abutment surfaces, according to the patent transferring the torsional moment. This is true, but only theoretically, if the abutment surfaces of the beam part and the support surfaces of the tongue part are in tight contact with each other. However, the installation tolerance problem has not been solved in the patent, i.e. how the abutment surfaces of the slot of the beam part and the tongue part can be installed tightly against each other, when there is manufacturing variation in the structures.
In a commercial bracket application of patent F183358, there was a clearance between the vertical, torsion-transferring abutment surfaces of the tongue part and the end plate of the beam part. The harmful rotation effect caused by the clearance in the beam was removed by installation support and wedging of the connection. The wedging method between the vertical abutment surfaces of the tongue and beam part did not work reliably, however, because vertical surfaces cannot be wedged with a tapering wedge tightly and non-rotationally in a reliable way. The torsion-transfer capability described in the patent could thus not be solved in the practical application without supporting the beam for torsion in the installation situation. In the final use situation, the vertical abutment surfaces of the connection were able to receive the torsional moment, because rotation of the beam was not critical anymore after casting the concrete. Because of the shortcomings of the patent, the torsional moment could not be transferred reliably in the most critical installation situation without installation support of the beam. The practical application of patent FI83358 did therefore not reliably solve the problem of torsion/rotation of the bracket.
Patent EP 1334244 discloses a rectangular-shaped tongue part (like patent FI83358 ), but this bracket has not been designed for transferring torsional moment. The commercial applications of the patent and its bracket do not allow torsional moment for the bracket, and no abutment surfaces receiving the torsional moment have been formed in it due to large clearances of the connection surfaces of the bracket. The commercial application of the patent uses installation support that removes the torsional moment.
DE 4313895 A1 a connection arrangement for a vertical element, such as column, and a beam to each other. The connection arrangement comprises a beam part to be fastened to the end of the beam and comprising an end plate having a downwardly open slot, at the bottom of which there is an abutment surface. The connection arrangement further comprises a column part to be fastened to the vertical element, which column part comprises a tongue part having a support surface against which the abutment surface of the slot is arranged to be supported to receive a vertical load.
The object of this invention is to provide an improved connection arrangement for connecting a vertical element, such as a column, and a horizontal element, such as a beam, to each other.
The object according to the invention is achieved by the connection arrangement according to patent 1, comprising a beam part to be fastened to an end of the beam, which beam part comprises an end plate in which there is a downwardly open slot, at the bottom of which there is an abutment surface, and a column part to be fastened to the vertical element, which column part comprises a tongue part having a support surface against which the abutment surface of the slot is arranged to be supported in order to receive a vertical load when the beam part has been installed onto the column part. In an upper part of the slot, on opposite sides, there are upper abutment surfaces, and in a lower part of the slot there are, on opposite sides, lower abutment surfaces, the horizontal distance between which lower abutment surfaces is greater than between the upper abutment surfaces. In an upper part of the tongue part there are, on opposite sides, upper support surfaces, against one of which the upper abutment surface of the slot is arranged to be supported when the beam part has been installed onto the column part and a torsional moment acts on the beam part. In a lower part of the tongue part, on opposite sides, there are lower support surfaces, the horizontal distance between which is greater than between the upper support surfaces and against one of which the lower abutment surface of the slot is arranged to be supported when the beam part has been installed onto the column part and a torsional moment acts on the beam part.
The lower abutment surfaces of the slot are partly vertical and the lower support surfaces of the tongue part are partly vertical. The column part comprises a fastening part provided with an internal thread and the beam part comprises a horizontal plate provided with a screw hole, through which a screw is turned onto the thread of the fastening part to prevent horizontal and vertical movement between the column part and the beam part. Moreover, the beam part comprises a U-shaped housing, the ends of its sides being fastened to the back surface of the end plate on either side of the slot, and the horizontal plate is arranged in a space defined by the housing and the end plate and fastened to the housing and to the back surface of the end plate.
The invention provides significant advantages. In the connection arrangement according to the invention, there are normal installation clearances required during installation. At the end of installation the connection arrangement can be locked by the connection surfaces transferring the torsional moment without harmful rotation occurring in the beam.
One embodiment of the invention specifically relates to a bracket connection between composite and steel columns and composite beams. The connection may also be used for connecting concrete beams. In this embodiment a new kind of tongue part of the column part is used, onto which tongue part the beam part is lowered. Additionally, the slot of the end plate of the beam part and the internal structure of the beam part have been formed in such a way that the requirements relating to the installation clearances and to the torsional moment may be reliably satisfied. In this embodiment the tongue part and the beam part of the connection are shaped in such a way that different beam and column materials may be connected by means of the connection. The implementation of the tongue part and the end plate of the beam part thus allows different frame materials got the beam and the column with one and the same configuration of the tongue part.
The installation tolerances and clearance of the connection in the installation situation, i.e. in a situation where the connection arrangement has not been locked immovable, are achieved such that the shape of the tongue part of the column part and the shape of the slot of the beam part form the clearance of the connection which is required at the beginning of installation as the beam part is installed from above onto the column part. The width of the lower part of the slot of the beam part is greater than the width of the upper part of the tongue part, whereby the tongue part has space in the horizontal direction inside the slot at the beginning of installation. When the beam part has been lowered onto the tongue part, the clearances of the connection are removed due to the shape of the tongue part and the shape of the slot of the beam part, and at the end of installation the support surfaces of the tongue part and the abutment surfaces of the slot come against each other or to a distance of the installation clearance from each other, thus allowing the transfer of torsional moment and preventing rotation of the beam part about the longitudinal axis of the beam.
The tongue part comprises a support surface onto which the beam part is supported. The support surface receives the vertical load of the beam. In one embodiment of the invention the side surfaces of the tongue part are partly vertical and partly inclined in such a way that the upper part of the tongue part is narrower than the lower part, whereby the width of the tongue part increases in the downward direction. In the end plate of the beam part there is a slot, the shape of which corresponds to the shape of the sides of the tongue part, whereby the width of the slot increases in the downward direction. This design forms a spacious structure in the beginning of installation when the beam is lowered in the downward direction. The torsional moment transferring support surfaces of the tongue part and the abutment surfaces of the slot of the beam part are not supported to each other until the beam part has been lowered onto the tongue part. This way, additional play does not need to be formed in the connection for installation tolerances, but this play is provided by the downwardly widening structural design of the tongue part and the slot of the beam part.
The transfer of torsional moment requires that the connection has two vertical abutment surfaces located in the horizontal direction on opposite sides of the connection. In addition, the surfaces must be located at a different height in the vertical direction. It is always more advantageous for the transfer of torsional moment the more there is height difference between the abutment surfaces in the vertical direction. In the upper part of the tongue part there is a vertical upper support surface for transferring the torsional moment. Likewise in the lower part of the tongue part there is a vertical lower support surface for transferring the torsional moment. For structural symmetry, there are two of such surfaces located symmetrically in the upper part and in the lower part on both sides of the tongue part, of which surfaces only those located on opposite sides of the tongue part transfer the torsional moment at the same time. It is furthermore new in this invention that the horizontal distance between the symmetrical abutment surfaces of the upper part is smaller than the horizontal distance between the abutment surfaces of the lower part. With this design a necessary installation clearance and torsional resistance are obtained for the connection. In addition, in one embodiment of the invention these surfaces need not be exactly vertical but may have slight symmetrical inclination, providing a tight contact between the connection surfaces at the end of installation.
In one embodiment of the invention, all connection parts of the beam part are connected together by means of the same housing structure. The housing of the beam part may be manufactured from a steel plate bent into a U-shape, which steel plate has been manufactured for example by rolling, which provides very small manufacturing tolerances. A U-shaped housing is also from the manufacturing point of view the most economical solution, the like of which there is none in the prior art.
In one embodiment of the invention, between the vertical side of the column and the end plate of the beam part there is, in the installation situation, a clearance in the longitudinal direction of the beam as required for installation. This clearance is needed because of the installation tolerances of the frame of the building. This clearance for displacement in the longitudinal direction of the beam and at the same time an upwardly directed force may be locked by providing the tongue part with a vertical screw connection, the screw of which prevents a horizontal and vertical displacement of the beam part after installation.
The invention will now be described in more detail by way of examples with reference to the accompanying drawings, in which

Fig. 1 illustrates a connection arrangement according to one embodiment of the invention as a side view cut from a plane of a side surface of a tongue part,
Fig. 2 illustrates a column part of the connection arrangement of Fig. 1 as a front view,
Fig. 3 illustrates a beam part of the connection arrangement of Fig. 1 as seen from the direction of the beam and cut at a rear part of a housing of the beam part,
Fig. 4 illustrates a beam part and a tongue part of the connection arrangement of Fig. 1 as seen from the direction of the beam and cut at a rear part of a housing of the beam part,
Fig. 5 illustrates a beam part and a tongue part of the connection arrangement of Fig. 1 as seen from above and cut from a plane of the upper surface of the tongue part.

Fig. 1-5 illustrate a connection arrangement according to one embodiment of the invention for connecting a vertical element, such as a column 2 or a wall element, and a beam 3 to each other. The connection arrangement is a so-called hidden bracket in which the connection is disposed inside the beam 3 and the column 2. The beam 3 may be a composite beam comprising an enclosure-like space 4 defined by steel plates 3, which space is filled with concrete. The beam 3 is typically a composite beam, but it may in another embodiment be also a concrete beam. The column 2 may be a composite column comprising steel plates 2, an enclosure-like space 1 defined by which steel plates is filled with concrete. The column 2 may also be a steel column without concrete filling.
The connection arrangement comprises a beam part fastenable to an end of the beam. The beam part comprises an end plate 12 in which there is a downwardly open slot 11. The slot 11 extends through the end plate 12 along the thickness thereof. A housing 13, for example a U-shaped housing, is fastened to a back surface of the end plate 12, i.e. to the surface to be arranged towards the end of the beam 3. One side of the housing may be open. The housing 13 comprises two side walls and a back wall, which are formed for example from a steel profile bent to a U-shape. The ends of the side walls of the housing 13 are symmetrically fastened to the end plate 12 on opposite sides of the slot 11. The housing 13 is downwardly open. The housing 13 protects the parts of the connection arrangement inside the beam from concrete and forms a space for lowering the beam part onto a column part.
The beam part comprises a horizontal plate 14 provided with a screw hole 71. The screw hole 71 is round or oval-shaped. The horizontal plate 14 is arranged inside the space defined by the housing 13 and the end plate 12. The horizontal plate 14 is fastened to the housing 13, for example to an inner surface of the housing 13, and to the back surface of the end plate 12, i.e. to the surface of the end plate 12 to be arranged towards the end of the beam. The back surface of the end plate 12 is fastened by welding to the structures or to the surface of the end of the beam 3.
As shown in Fig. 3, the slot 11 of the end plate 12 is shaped in such a way that in an upper part of the slot 11 the opposite sides form upper abutment surfaces 19. The upper abutment surfaces 19 may be the uppermost surfaces of the sides of the slot 11. The opposite upper abutment surfaces 19 are vertical. Alternatively the upper abutment surfaces 19 may be slightly inclined in such a way that the upper abutment surfaces are symmetrical with respect to the vertical central axis of the slot 11.
In a lower part of the slot 11 the opposite sides of the slot 11 form inclined lower abutment surfaces 20. The lower abutment surfaces 20 may be the lowermost surfaces of the sides of the slot 11. The lower abutment surfaces 20 are inclined relative to the vertical central axis of the slot 11. The horizontal distance between the opposite lower abutment surfaces 20 and the width of the slot 11 increases towards the open lower part of the slot 11. The lower abutment surfaces 20 may also comprise vertical portions. The lower abutment surfaces 20 and/or the upper abutment surfaces 19 of the opposite sides of the slot 11 are symmetrical with respect to the vertical central axis of the slot 11. The width of the slot 11 is greater at the lower abutment surfaces 20 than at the upper abutment surfaces 19. The lower abutment surfaces 20 may be inclined without vertical portions. Thus, the horizontal distance between the lower abutment surfaces 20 increases in the downward direction. Alternatively the lower abutment surfaces 20 may be partly inclined and/or partly vertical. Alternatively the lower abutment surfaces 20 may be vertical without inclined portions, or the lower abutment surfaces 20 may be oriented at an angle of no more than 3-5 degrees to the vertical direction. Along the thickness of the end plate 12 the upper abutment surfaces 19 and the lower abutment surfaces 20 are parallel to the longitudinal axis of the beam 3. At the bottom or end of the slot 11 there is an abutment surface 21 to be supported onto a support surface 22 of a tongue part 8 in order to receive a vertical load when the beam part has been laid onto a column part.
The connection arrangement comprises a column part fastenable to the column 2. The column part comprises a tongue part 8, a back surface of which is arranged against a vertical surface of the column. In addition, the column part comprises a fastening part 5 for fastening the column part to the column. The fastening part 5 is fastened to the tongue part 8, for example to the back surface of the tongue part 8. The fastening part 5 extends to the concrete in the column and thus transfers a load from the tongue part 8 to the column. The fastening part 5 may comprise plate-like parts manufactured from example from a steel plate.
The tongue part 8 comprises a support surface 22 against which the abutment surface 21 of the slot 11 is supported when the beam part has been laid onto the column part. The support surface 22 is on an upper surface of the tongue part. An end support 9 is fastened for example by welding to a front surface of the tongue part 8, which end support is for example a plate preventing the end plate 12 of the beam part from falling from the tongue part 8 when the beam part moves in the longitudinal direction of the beam. The end support 9 extends higher than the support surface 22 of the tongue part 8. The support surface 22 of the tongue part 8 is longer than the support surface 21 of the slot 11, i.e. the extent of the support surface 22 of the tongue part in the longitudinal direction of the beam is greater than that of the abutment surface 21 of the slot 11. Thus, the abutment surface 21 of the slot is able to move along the support surface 22 of the tongue part in the longitudinal direction of the beam.
The connection arrangement comprises a screw 15 for fastening the beam part to the column part and for preventing a horizontal and vertical movement of the beam part. The column part comprises a fastening part 10 provided with an internal thread, into which fastening part the screw 15 is turned. The fastening part 10 is fastened for example by welding to the front surface of the tongue part 8 or to the end support 9, typically to a front surface of the end support 9. The fastening part 10 may be a socket into which the screw 15 is turnable. The screw 15 is inserted through the screw hole 71 of the horizontal plate 14 of the beam part and turned into the fastening part 10. The horizontal plate 14 is located higher than the tongue part 8 when the beam part has been installed onto the column part.
The tongue part 8 is shaped in such a way that in an upper part of the tongue part 8 the opposite sides form upper support surfaces 16. The opposite upper support surfaces 16 are parallel. The opposite upper support surfaces 16 are vertical. The upper support surfaces 16 may be the uppermost surfaces on the sides of the tongue part 8. In a lower part of the tongue part 8 the opposite sides form inclined lower support surfaces 18. The lower support surfaces 18 may be the lowermost surfaces on the sides of the tongue part 8. The lower support surfaces 18 are inclined relative to the vertical central axis of the tongue part 8. The horizontal distance between the opposite lower support surfaces 18 and thereby the width of the tongue part 8 increases towards the lower part of the tongue part 8. Between the upper support surfaces 16 and the lower support surfaces 18 there may be inclined connecting surfaces 17. The upper support surfaces 16 and/or the lower support surfaces 18 of the opposite sides are symmetrical with respect to the vertical central axis of the tongue part 8. The width of the tongue part 8 is greater at the lower support surfaces 18 than at the upper support surfaces 16. The lower support surfaces 18 may be inclined without vertical portions. Thus, the horizontal distance between the lower support surfaces 18 increases in the downward direction. Alternatively the lower support surfaces 18 may be partly inclined and/or partly vertical. Alternatively the lower support surfaces 18 may be vertical without inclined portions, or the lower support surfaces 18 may be oriented at an angle of no more than 3-5 degrees to the vertical direction. Along the thickness of the tongue part 8 the upper support surfaces 16 and the lower support surfaces 18 are parallel to the longitudinal axis of the beam 3.
The shape and orientation of the upper abutment surfaces 19 of the slot 11 of the end plate 12 correspond to the shape and orientation of the upper support surfaces 16 of the tongue part 8. When the beam part has been installed onto the column part there is, between both upper support surfaces 16 and upper abutment surfaces 19, an installation clearance of 0.5-3 mm, typically 1-2.5 mm. A combined installation clearance between both upper support surfaces 16 and upper abutment surfaces 19 is thus 1-6 mm, typically 2-5 mm. Thus the width of the tongue part 8 at the upper support surfaces 16 is smaller than the width of the slot 11 at the upper abutment surfaces 19 to the extent of the combined installation clearance, i.e. 1-6 mm, typically 2-5 mm. Correspondingly, when the beam part has been installed onto the column part there is, between both lower support surfaces 18 and lower abutment surfaces 20, an installation clearance of 2-5 mm, typically 3-4 mm. A combined installation clearance between both lower support surfaces 18 and lower abutment surfaces 20 is thus 4-10 mm, typically 6-8 mm. Alternatively, the lower support surfaces 18 and the lower abutment surfaces 20 may be provided without the installation clearance, whereby the lower support surfaces 18 are against the lower abutment surfaces 20 when the beam part has been installed onto the column part.
The shape and orientation of the lower abutment surfaces 20 of the slot 11 correspond to the shape and orientation of the lower support surfaces 18 of the tongue part 8. The width of the slot 11 at a lower point of the lower abutment surfaces 20 is greater than the width of the slot 11 at the upper abutment surfaces 19. The width of the slot 11 at a lower point of the lower abutment surfaces 20 is greater than the width of the tongue part 8 at the support surface 22 and/or at the upper support surfaces 16. Typically, the width of the slot 11 at a lower point of the lower abutment surfaces 20 is at least 1 cm, for example 2-2.5 cm greater than the width of the tongue part 8 at the support surface 22 and/or at the upper support surfaces 16. Due to this difference in width, there is initially space in the slot 11 for lowering the beam part from above onto the tongue part 8. The connection does not sit tightly until the beam part has been lowered to its place onto the column part. Then the upper abutment surface 19 of the slot 11 comes to a distance of the installation clearance from the upper support surface 16 of the tongue part 8.
When using the connection arrangement the column part is fastened to the vertical element, for example to the column 2, and the beam part is fastened to the end of the beam 3. After this, the beam part is brought over the column part in such a way that the slot 11 of the end plate 12 is located above the tongue part 8. The beam 3 is lowered down, whereby the slot 11 descends over the sides and the top of the tongue part 8. When the beam 3 has been lowered to its place, the abutment surface 21 of the slot is supported against the support surface 22 of the tongue part 8. The lower abutment surfaces 20 of the slot 11 are at a distance of the installation clearance from the lower support surfaces 18 of the tongue part 8 or the lower support surfaces 18 are against the lower abutment surfaces 20. The upper abutment surfaces 19 of the slot 11 are at a distance of the installation clearance from the upper support surfaces 16 of the tongue part 8. The end support 9 prevents the end plate 12 from falling from the tongue part 8 if the beam 3 moves in the longitudinal direction.
A torsional moment tending to rotate the beam 3 about the longitudinal axis is transferred from the end plate 12 to the tongue part 8 via support between the upper abutment surface 19 and the upper support surface 16 as well as the lower abutment surface 20 and the lower support surface 18. Thus the upper abutment surface 19 of the slot 11 is supported against the upper support surface 16 when the beam part has been installed onto the column part and a torsional moment tending to cause rotation about the longitudinal axis of the beam acts on the beam part. Additionally, the lower abutment surface 20 of the slot 11 is supported against the lower support surface 18 when the beam part has been installed onto the column part and a torsional moment tending to cause rotation about the longitudinal axis of the beam acts on the beam part. The upper support surface 16 and the lower support surface 18 of the tongue part, to which surfaces the upper abutment surface 19 and the lower abutment surface 20 of the slot are supported, are located on opposite sides of the tongue part 8. If the direction of the torsional moment tending to rotate the beam is opposite, the other upper abutment surface 19 of the slot is supported against the other upper support surface 16 of the tongue part and the other lower abutment surface 20 against the other lower support surface 18. The longitudinal axis of the beam 3 is parallel to the normal of the back surface of the end plate 12.
When the beam part has been installed in its place onto the column part, the beam part is able to move in the longitudinal direction of the beam as allowed by the length difference between the support surface 22 of the tongue part 8 and the abutment surface 21 of the end plate 12, when the beam part has not been locked to the column part with the screw 15. The screw 15 is turned into the fastening part 10 through the screw hole 71 in the horizontal plate 14. The horizontal plate 14 is disposed between the head of the screw 15 and the fastening part 10. The screw 15 prevents the beam part from moving in the horizontal and vertical directions. In addition, a force lifting the beam 3 is transferred to the column part by means of the screw 15.
In one embodiment of the invention the upper abutment surfaces 19 and the lower abutment surfaces 20 of the slot 11 are vertical, and on both sides of the slot 11 there is an inclined connecting surface between the upper abutment surface 19 and the lower abutment surface 20. The upper support surfaces 16 and the lower support surfaces 18 of the tongue part 8 are vertical, and on both sides of the tongue part 8 there is an inclined connecting surface 17 between the upper support surface 16 and the lower support surface 18. Between the inclined connecting surfaces 17 of the tongue part 8 and the inclined connecting surfaces of the slot 11 there is a clearance when the beam part has been installed onto the column part. This may be implemented for example such that the height of the vertical upper abutment surfaces 19 is unequal to, typically smaller than, the height of the vertical upper support surfaces 16, and the height of the vertical lower abutment surfaces 20 is unequal to, typically greater than, the height of the vertical lower support surfaces 18. Thus the inclined connecting surfaces of the slot 11 are at a distance from the inclined connecting surfaces 17 of the tongue part 8 when the beam part has been installed onto the column part.
It is obvious to a person skilled in the art that the invention is not limited to these solutions only. The invention and its embodiments may thus vary within the scope of the claims.

Claims

A connection arrangement for connecting a vertical element (2), such as a column or a wall element, and a beam (3) to each other, the connection arrangement comprising:
- a beam part to be fastened to an end of the beam (3), which beam part comprises an end plate (12) in which there is a downwardly open slot (11), at the bottom of which there is an abutment surface (21), and

- a column part to be fastened to the vertical element (2), which column part comprises a tongue part (8) having a support surface (22) against which the abutment surface (21) of the slot (11) is arranged to be supported in order to receive a vertical load,
wherein- in an upper part of the slot (11), on opposite sides, there are upper abutment surfaces (19), and in a lower part of the slot (11) there are, on opposite sides, lower abutment surfaces (20), the horizontal distance between which lower abutment surfaces (20) is greater than between the upper abutment surfaces (19),
- in an upper part of the tongue part (8) there are, on opposite sides, upper support surfaces (16), against one of which the upper abutment surface (19) of the slot (11) is arranged to be supported when the beam part has been installed onto the column part and a torsional moment tending to cause rotation about the longitudinal axis of the beam acts on the beam part, and

- in a lower part of the tongue part (8), on opposite sides, there are lower support surfaces (18), the horizontal distance between which is greater than between the upper support surfaces (16) and against one of which the lower abutment surface (20) of the slot (11) is arranged to be supported when the beam part has been installed onto the column part and a torsional moment tending to cause rotation about the longitudinal axis of the beam acts on the beam part, characterized in that

- the lower abutment surfaces (20) of the slot (11) are partly vertical and the lower support surfaces (18) of the tongue part (8) are partly vertical,

- the column part comprises a fastening part (10) provided with an internal thread and the beam part comprises a horizontal plate (14) provided with a screw hole (71), through which screw hole (71) a screw (15) is turned onto the thread of the fastening part (10) to prevent horizontal and vertical movement between the column part and the beam part,

- the beam part comprises a U-shaped housing (13), the ends of its sides being fastened to the back surface of the end plate (12) on either side of the slot (11), and

- the horizontal plate (14) is arranged in a space defined by the housing (13) and the end plate (12) and fastened to the housing (13) and to the back surface of the end plate (12).
The connection arrangement according to claim 1, characterized in that the lower abutment surfaces (20) of the slot (11) are inclined in such a way that the horizontal distance between the lower abutment surfaces (20) increases in the downward direction, and the lower support surfaces (18) of the tongue part (8) are inclined in such a way that the horizontal distance between the lower support surfaces (18) increases in the downward direction, or the lower abutment surfaces (20) and the lower support surfaces (18) are vertical without inclined portions.
The connection arrangement according to any one of the preceding claims, characterized in that the upper abutment surfaces (19) of the slot (11) are vertical and the upper support surfaces (16) of the tongue part (8) are vertical.
The connection arrangement according to any one of the preceding claims, characterized in that between the upper support surface (16) of the tongue part (8) and the upper abutment surface (19) of the slot (11) there is an installation clearance and/or between the lower support surface (18) of the tongue part (8) and the lower abutment surface (20) of the slot there is an installation clearance when the beam part has been installed onto the column part.
The connection arrangement according to claim 4, characterized in that the installation clearance between the upper support surface (16) and the upper abutment surface (19) is 0.5-3 mm and/or the installation clearance between the lower support surface (18) and the lower abutment surface (20) is 2-5 mm.
The connection arrangement according to any one of the preceding claims 1-3, characterized in that the lower support surfaces (18) of the tongue part (8) and the lower abutment surfaces (20) of the slot (11) are provided without the installation clearance, whereby the lower support surfaces (18) are against the lower abutment surfaces (20) when the beam part has been installed onto the column part.
The connection arrangement according to any one of the preceding claims, characterized in that an end support (9) extending higher than the support surface (22) is fastened to a front surface of the tongue part (8).
The connection arrangement according to claim 1 and 7, characterized in that the fastening part (10) is fastened to the end support (9) or to the front surface of the tongue part (8) and the horizontal plate (14) is fastened to a back surface of the end plate (12).
The connection arrangement according to any one of the preceding claims, characterized in that the upper abutment surfaces (19) and the lower abutment surfaces (20) are vertical, and the slot (11) comprises an inclined connecting surface between the upper abutment surface (19) and the lower abutment surface (20), and the upper support surfaces (16) and the lower support surfaces (18) are vertical, and the tongue part (8) comprises an inclined connecting surface (17) between the upper support surface (16) and the lower support surface (18), and there is a clearance between the inclined connecting surfaces (17) of the tongue part (8) and the inclined connecting surfaces of the slot (11) when the beam part has been installed onto the column part.
The connection arrangement according to claim 9, characterized in that the height of the vertical upper abutment surfaces (19) is unequal to, typically smaller than, the height of the vertical upper support surfaces (16), and the height of the vertical lower abutment surfaces (20) is unequal to, typically smaller than, the height of the vertical lower support surfaces (18).
A connection comprising a vertical element (2), such as a column or a wall element, and a beam (3), characterized in that the beam (3) is connected to the vertical element (2) with a connection arrangement according to any one of the preceding claims 1-10, a column part thereof being fastened to the vertical element (2), and a beam part thereof being fastened to an end of the beam (3), and the beam part is installed onto the column part in such a way that an abutment surface (21) of a slot (11) of the beam part is supported onto a support surface (22) of a tongue part (8), an upper abutment surface (19) of the slot (11) is supported against an upper support surface (16) of the tongue part (8) and a lower abutment surface (20) of the slot (11) is supported against a lower support surface (18) of the tongue part (8) when a torsional moment tending to cause rotation about the longitudinal axis of the beam acts on the beam part.