EP2888419B1 - Beam assembly and construction erected therewith - Google Patents

Description

The invention relates to a carrier arrangement with a substantially rectilinear carrier arranged between two bearings, which extends along a longitudinal direction and is composed of at least three longitudinally successive segments connected to one another via two top plate joints, namely a middle segment and two outer segments, wherein Bearings are hampered by the displacement in the longitudinal direction. The invention further relates to a constructed with such a carrier assembly construction, in particular a steel structure.

Steel girders often can not be made in one piece in the length required for the intended use and transported to the jobsite. Rather, prefabricated segments of lesser length are connected to each other on site at the construction site. This is often done via so-called head or face plate joints, in which the front side of the actual support profiles molded or attached head plates are bolted together. As a rule, such head plates are aligned perpendicular to the longitudinal direction of the carrier.

Steel structures in nuclear facilities, but also in other fields of application, especially heavily loaded main beams are often interpreted against high forced impacts resulting from temperature influences. On the other hand, they must be designed and stored so that all external loads such as payloads and induced vibrations, eg. B. from earthquakes, as evenly as possible can be removed. This is often in conflict with the desire for a constrained as possible storage to compensate for thermal expansion. In general, the reduction of stiffness is also associated with a reduction in carrying capacity.

Thus, thermal constraining forces have been taken into account in the past mainly by implementing an axial displaceability of the connection (restraint-free storage) using floating bearings or floating support bearings. This type of connection lacks sufficient axial rigidity for external dynamic stresses to distribute the loads homogeneously in the system. As a result, these constructions are economically unsatisfactory.

JP 952 94008 U discloses a carrier assembly according to the preamble of claim 1.

The invention has for its object to provide an alternative support arrangement, which allows a controlled reduction of thermal constraining forces while maintaining the load-bearing function and with a uniform distribution of external forces within the structure.

This object is achieved according to the invention by the features of independent claim 1.

• das Mittelsegment an seinen beiden Enden jeweils eine Mittelsegment-Kopfplatte aufweist und jedes der beiden Außensegmente an seinem zum Mittelsegment hin gerichteten Ende eine Außensegment-Kopfplatte aufweist,
• die jeweilige Außensegment-Kopfplatte derart komplementär zu der ihr gegenüberliegenden Mittelsegment-Kopfplatte ausgerichtet ist, dass sie zusammen einen Kopfplattenstoß bilden,
• die beiden Kopfplatten jedes Kopfplattenstoßes über Verbindungsschrauben oder Verbindungsbolzen miteinander verbunden sind, die durch Ausnehmungen in den Kopfplatten hindurch geführt sind,
• die Ausnehmungen in zumindest einer der Kopfplatten jedes Kopfplattenstoßes als Langlöcher ausgeführt sind, und
• beide Kopfplattenstöße derart gegensinnig gegenüber einer Normalebene auf der Längsrichtung geneigt sind und die Langlöcher derart angeordnet und ausgerichtet sind, dass bei einer thermischen Ausdehnung oder Kontraktion der Segmente eine seitliche Verschiebung des Mittelsegments relativ zu den beiden Außensegmenten, sprich quer zur Längsrichtung, möglich ist.

Accordingly, a carrier assembly of the type mentioned is provided, wherein

• the middle segment has a middle segment head plate at its two ends and each of the two outer segments has an outer segment head plate at its end directed towards the middle segment,
• the respective outer segment top plate is aligned in such a way that it is complementary to the middle segment top plate opposite it, that together they form a topplate impact,
• the two head plates of each headstock joint are interconnected via connecting bolts or connecting bolts passed through recesses in the head plates,
• the recesses in at least one of the head plates of each headstock impact are designed as slots, and
• both topplates are inclined in opposite directions relative to a normal plane in the longitudinal direction and the slots are arranged and aligned such that at a thermal expansion or contraction the segments a lateral displacement of the central segment relative to the two outer segments, that is transverse to the longitudinal direction, is possible.

The underlying problem is solved with a simple and economical steel construction. Only plates, rolled sections and screws in a slot connection are required, no special components. By simple combination of the above-named components, a reduction-reducing storage is achieved under the influence of temperature and at the same time maintaining the load capacity for external loads. The axial extent of the segments under thermal stress is compensated by lateral deflection of the structure perpendicular to the longitudinal direction. The high constraining forces overcome the static friction between the top plates, which is realized by a partial prestressing of the screw connection. The lateral deflection of the central segment of the carrier due to external static and / or dynamic loads, however, is not possible for structural reasons. After completion of the action of temperature, the segments contract again, whereby a laterally directed restoring force is automatically generated, which pushes the middle segment back to the starting position.

The rule of the design will be that the segments of the carrier lie in a line / flight at normal ambient temperature, and that the middle segment shifts sideways when there is a significant increase in temperature. But it can also be based on a system design, which responds in a corresponding manner to temperature drops and thus to contractions of the segments, and in a sense the shifted state is the ground state. If the connecting bolts or connecting bolts are in the ground state approximately in the middle of the slots and the middle segment is pushed out accordingly a little out of alignment, there is - depending on the nature of the temperature change - freedom of movement in both directions.

Advantageously, the inclination axis of the respective center segment head plate - and thus also the inclination axis of the head plate joint opposite outer segment head plate - aligned perpendicular to the longitudinal direction. Further, the pitch axes of the two center-segment top plates are preferably aligned parallel to each other, and the two center-segment top plates preferably have an equal tilt angle to a normal plane in the longitudinal direction. This angle of inclination is preferably in the range between 30 ° and 60 ° and is preferably 45 °. Thereby, the described, self-acting lateral displacement of the central segment due to thermal expansion of the segments is optimally supported, while the carrying capacity is maintained in the best possible way. Smaller deviations from the direction and angle specified above but are possible, for example by a slight twisting or torsion of the tilt axes or by slightly different inclination of the top plate joints.

The effective in the lateral displacement of the middle segment as a guide rails for the connecting screws or connecting bolts of each headstock impact slots are of course arranged and aligned in such a way in the corresponding top plate that this displacement is given. Suitably tuned to the geometry described above, the slots are aligned perpendicular to the pitch axis of the respective center segment top plate.

In a preferred variant, the recesses in the middle segment head plates of a top plate joint are designed as oblong holes and in the outer segment top plates as round holes. But it can also be the other way around. The connecting bolts or connecting bolts are expediently guided through both recesses, ie through both head plates of the top plate joint, and secured laterally from outside through the edges of the recesses, and by screw heads resting on the top plates and / or nuts. In one possible modification, however, the connecting bolts can also be formed or joined (for example welded) on at least one of the two head plates of a top plate joint, inserted through the land holes in the other top plate and secured from the outside by a nut.

Advantageously, the elongated holes are closed over the entire circumference, that is surrounded on all sides by the top plate, and not open to the outer border out. In this way, the lateral displacement of the central segment is limited, and the central segment can not fall laterally out of the carrier. The maximum lateral displacement of the middle segment is in a structurally realizable area. This ensures that the stability and load-bearing capacity of the carrier is not lowered below a critical value.

As already indicated, the two head plates of a headstock joint are expediently clamped or clamped against each other during the mounting of the carrier by releasable frictional connection elements. For this purpose, preferably connecting bolts are used, in particular in the form of bolts or threaded bolts and / or in the form of cap screws or similar, suitable for forming a screw elements with substantially cylindrical shaft, in the usual way by means of associated nuts - possibly in combination with washers - Or alternatively secured by means of dowel pin or the like and thereby loaded on train. Advantageously, the two head plates are braced against each other, for example by appropriately tightening the screws or nuts that the lateral displacement of the central segment is maintained under the influence of temperature (partial bias).

In an expedient embodiment, the carrier is a steel carrier whose individual segments are produced, for example, as rolled profiles with end plates molded or attached, in particular welded head plates. Alternatively, the carrier or at least some of its components can also be made of other materials, in particular of modern composite materials (composite materials) or the like. The individual carrier segments can in turn be segmented in a conventional manner, that is to say composed of originally separate subsegments - for example with head plate joints oriented perpendicular to the longitudinal direction. In principle, it is also possible, for example, a composite of five segments carrier in which the second and fourth segments seen in the longitudinal direction are designed for lateral displacement in the manner described. In this case, since the combination of the first to third segments or the combination of the third to fifth segments can be regarded as a single segment, such a configuration is covered by the wording of the claims.

The top plates preferably have flat contact surfaces, which allow a tilt-stable and torsionally rigid support and connection with their respective connection partner, and which form in the lateral displacement of the central segment of the wearer sliding surfaces. In an alternative embodiment, the contact surfaces may also have a step, which is aligned along the direction of displacement, so that a guide rail for the lateral displacement is realized. The head plates may, in particular in the case of solid beams or with closed box profiles have laterally beyond the support profiles flanges to facilitate the attachment of the fasteners and access to them during installation and maintenance. Alternatively, with closed and / or solid profiles, corresponding access openings can also be made in the material.

The support arrangement described is expediently part of a steel construction or a structure, in particular a steel platform or a supporting framework, for example in a nuclear facility or in any other industrial plant.

The inventive concept is suitable for new construction of steel structures and also for the upgrading of existing steel structures. The geometry of the structure is virtually unaffected, and extensive prefabrication of the support connection in the workshop is possible.

The advantages achieved by the invention are in particular that, by the segmented design of a carrier whose individual segments by partially prestressed top plate joints with slot screw connections and with dedicated connection geometry are connected to each other, a controlled reduction of stresses from thermal constraints by lateral evasion while maintaining the bending capacity for external loads in thermally, statically and dynamically loaded constructions is feasible, namely with simple, steel construction principles without special components.

• eine biegesteife, lasttragende Verbindung in der Arbeits- bzw. Einbauposition,
• eine zusätzliche konstruktive Möglichkeit zum Abbau von Zwangsbeanspruchungen in Stahlkonstruktionen,
• eine wirtschaftlichere Auslegung als bislang aufgrund von Materialersparnis in der Gesamtkonstruktion, und
• eine Vereinigung von Ausdehnung unter thermischer Beanspruchung und zugleich Erhalt der Tragfähigkeit für äußere Lasten in einer einzigen Konstruktion.

It turns out that way

• a rigid, load-bearing connection in the work or installation position,
• an additional constructional option for reducing forced loads in steel structures,
• a more economical design than hitherto due to material savings in the overall construction, and
• a union of expansion under thermal stress while preserving the load capacity of external loads in a single construction.

FIG. 1

einen Längsschnitt durch einen erfindungsgemäßen Träger in einer ersten Konfiguration bei Umgebungstemperatur,

FIG. 2

einen Schnitt durch den Träger gemäß FIG. 1 entlang der dort mit A-A bezeichneten Schnittlinie,

FIG. 3

einen Schnitt durch den Träger gemäß FIG. 1 entlang der dort mit B-B bezeichneten Schnittlinie,

FIG. 4

einen Längsschnitt durch den Träger gemäß FIG. 1 in einer zweiten Konfiguration bei erhöhter Temperatur, und

FIG. 5

einen Schnitt durch den Träger gemäß FIG. 4 entlang der dort mit C-C bezeichneten Schnittlinie.

An embodiment of the invention will be explained in more detail with reference to drawings. In each case, in a simplified and schematic representation:

FIG. 1

a longitudinal section through a carrier according to the invention in a first configuration at ambient temperature,

FIG. 2

a section through the carrier according to FIG. 1 along the section line labeled AA there,

FIG. 3

a section through the carrier according to FIG. 1 along the section line labeled BB there,

FIG. 4

a longitudinal section through the carrier according to FIG. 1 in a second configuration at elevated temperature, and

FIG. 5

a section through the carrier according to FIG. 4 along the section line labeled CC.

Identical parts are provided with the same reference numerals in all figures.

The in FIG. 1 in a longitudinal section at ambient temperature (.DELTA.T = 0) shown support 2 is designed as an elongated, straight steel beam, which is clamped in the example in vertical alignment between an upper bearing 4 and a lower bearing 6 here. The total length of the carrier 2 in the longitudinal direction 8 is denoted by L. The two bearings 4, 6 are hindered from displacement in the longitudinal direction 8, for example by an adjacent construction or anchoring. In particular, it may be fixed storage. In other constructions, the carrier 2 could also be arranged horizontally or obliquely.

The carrier 2 is constructed of three originally separate, prefabricated in a workshop and assembled at the site of construction and interconnected segments 10, 12, 14, namely a middle segment 10, an upper outer segment 12 and a lower outer segment 14. Each of the three segments 10th , 12, 14 has a carrier element 16 formed, for example, from a symmetrical double T-profile. The profile of the carrier 2 is substantially constant over the entire extension length. Of course, other profiles can be used. Optionally, the three segments 10, 12, 14 may also have different and / or varying profiles in the longitudinal direction.

To accomplish the connections, the middle segment 10 is provided at each end with a flat mid-segment top plate 18 welded to the support member 16. The two outer segments 12, 14 have in appropriate presentation, in each case on its middle segment 10 towards the end facing an outer segment head plate 20, so that in the final assembly state, two head plate joints 22 are formed. In each of the two top plate joints 22, the outwardly directed contact surfaces of the connection partners involved are flat over the entire lateral extent.

In order to allow a possible zwängungsfreie storage of the carrier 2 between the two bearings 4, 6 while maintaining a high Biegetragfähigkeit, the top plate joints 22 are designed with a specific inclination. Specifically, the two middle segment head plates 18 are inclined in opposite directions to a respective imaginary tilt axis 24 relative to the horizontal arranged / tilted. Both inclination axes 24 parallel to each other and perpendicular to the longitudinal direction 8, here in FIG. 1 perpendicular to the image plane and through the symmetry axis of the carrier profile. Each of the two mid-segment head plates 18 occupies an inclination angle α of 45 ° with respect to the horizontal (and thus also with respect to the vertical), or more generally expressed in relation to a normal plane in the longitudinal direction 8. Due to the opposing inclination, the two middle segment head plates 18 in the sectional view according to FIG. 1 to make a lying V, if extended to the left accordingly. The outer segment top plates 20 are inclined in a complementary, complementary manner. The support elements 16 of the three segments 10, 12, 14 are cut correspondingly inclined at the end-side connections (similar to mitred corner joints), and the top plates 18, 20 are welded to the front edges of the support members 16. The middle segment 10 therefore has in FIG. 1 the outline of an isosceles, symmetrical trapezoid.

A permanent connection of the head plate in the respective thrust 22 opposite each other head plates 18, 20 carried by screwing. For this purpose, the top plates 18, 20 as shown in FIG FIG. 2 and FIG. 3 provided with suitably positioned recesses 26 and holes provided through the threaded bolt 28, preferably with two opposing threaded portions in the two end regions, inserted through and secured from both sides by screwing, the recesses laterally overlapping and resting on the top plates nuts 30 are secured. Alternatively, the use of cap screws is possible, which are each tightened by a single nut.

Specifically, in the present embodiment, the recesses 26 in the respective outer segment head plate 20 as round holes 32 with slightly larger Diameter than the diameter of each inserted through threaded bolt 28 or screw shaft executed ( FIG. 2 ). The recesses 26 in the respective middle segment head plate 18 are designed as elongated holes 34, the width of which is also dimensioned slightly larger than the diameter of the respective threaded bolt 28 to be inserted or screw shank, whose length, however, is significantly greater than the width ( FIG. 3 ).

The longitudinal direction 36 of the elongated holes 34 in the respective middle segment head plate 18 extends in the final assembly position perpendicular to the axis of inclination 24, here parallel to the image plane of FIG. 1 , The elongated holes 34 are positioned in relation to the round holes 32 such that at the in FIG. 1 illustrated configuration, in which the three segments 10, 12, 14 in the longitudinal direction 8 seen in a line / run, the threaded bolts 28 or Schraubenschafte tend to be positioned on the long base side of the trapezoid zugendenten end of the slots 34, in FIG. 2 so at the right end.

The construction described has the consequence that at a temperature increase (.DELTA.T> 0) by the concomitant expansion efforts of the three segments 10, 12, 14 in the longitudinal direction 8 and the fixed clamping of the two outer segments 12, 14 between the two bearings 4, the sixth the middle segment 10 experiences a resultant force transversely to the longitudinal direction 8, towards the long base side of the trapezoid - in this case to the right.

In accordance with the set bias of the screw this leads to the fact that when exceeding a required to overcome the static friction between the head plates 18, 20 of the two head plate joints 22 minimum temperature difference .DELTA.T compared to FIG. 1 underlying initial state, the middle segment 10 shifts in the direction mentioned, so evades the side. The contacting contact surfaces of the head plates 18, 20 cause on the one hand the force deflection transverse to the longitudinal direction 8, and on the other hand they form mutually sliding surfaces. The elongated holes 34 in the middle segment head plates 18 provide the required translational degree of freedom and also form a guide rail for the relative to her in the direction of in FIG. 2 marked free space, here to the left, sliding threaded bolt 28 or Schraubenschafte.

The higher the temperature difference ΔT, the greater the lateral displacement of the middle segment. The displacement is limited by the finite longitudinal extent of the sealed at both ends slots 34th

The state of maximum displacement is in FIG. 4 represented (ΔT >> 0). The threaded bolts 28 or Schraubenschafte are now on the short base side of the trapezoid facing the ends of the slots 34, the remaining material webs between the slots 34 and the outer border of the middle segment head plates 18 act as end stops ( FIG. 5 ). The total combined length of the three segments 10, 12, 14, measured at the symmetry axis of the beam profile, has increased from the original L1 + L2 + L3 to (L1 + ΔL1) + (L2 + ΔL2) + (L3 + ΔL3). The difference between these two measures is in FIG. 4 denoted by f _a . Due to the lateral displacement of the central segment 10 by the path fq, the overall length L of the carrier 2 has remained the same. In this special case, L1 = L3 and thus at least approximately ΔL1 = ΔL3, but this symmetry is generally not absolutely necessary.

Only at a further increase in temperature, a significant restraining of the carrier 2 would occur, which could lead to a corresponding crushing or bending deformation of the carrier 2 or yielding of the bearings 4, 6 or shearing the threaded bolt 28 or Schraubenschafte.

The displacement of the middle segment 10 is reversible. You can also see the in FIG. 4 illustrated configuration as the initial state for a subsequent temperature reduction and corresponding contraction of the segments 10, 12, 14 on which then to the in FIG. 1 configuration shown leads.

LIST OF REFERENCE NUMBERS

2

carrier

4

upper bearing

6

lower camp

8th

Longitudinal direction (of the carrier 2)

10

middle segment

12

Upper outer segment

14

lower outer segment

16

support element

18

Middle segment headstock

20

Outer segment headstock

22

Headstock shock

24

tilt axis

26

recess

28

threaded bolt

30

mother

32

round hole

34

Long hole

36

Longitudinal direction (the slots 34)

α

tilt angle

Claims (13)

1. A beam assembly comprising a substantially straight beam (2), which is arranged between two bearings (4, 6) and extends in a longitudinal direction (8) and is composed of at least three segments (10, 12, 14), which are arranged one behind the other in the longitudinal direction (8) and which are connected to each other by means of two head-plate joints (22), namely a middle segment (10) and two outer segments (12, 14), wherein the bearings (4, 6) are prevented from moving in the longitudinal direction (8) and wherein

   • the middle segment (10) has a middle-segment head plate (18) at each of its two ends and each of the two outer segments (12, 14) has an outer-segment head plate (20) at its end facing towards the middle segment (10),

   • each outer-segment head plate (20) is oriented complementarily to the middle-segment head plate (18) which is opposite to it, in such a way that together, they form a head-plate joint (22),

   • the two head plates (18, 20) of each head-plate joint (22) are connected to each other by means of connecting bolts (28), which are inserted through openings (26) in the head plates (18, 20),

   characterized in that

   • the openings (26) in at least one of the head plates (18) of each head-plate joint (22) are designed as elongated holes (34), and

   • both head-plate joints (22) are inclined in opposite directions with respect to a plane normal to the longitudinal direction (8) in such a way, and the elongated holes (34) are arranged and oriented in such a way, that a lateral displacement of the middle segment (10) in relation to the two outer segments (12, 14) is possible in the event of a thermal expansion or contraction of the segments (10, 12, 14).
2. The beam assembly of claim 1, wherein the axis of inclination (24) of each middle-segment head plate (18) is oriented vertically to the longitudinal direction (8).
3. The beam assembly of claim 2, wherein the axes of inclination (24) of the two middle-segment head plates (18) are oriented in parallel to each other.
4. The beam assembly of claim 3, wherein the two middle-segment head plates (18) have an identical angle of inclination (α) against a normal plane in the longitudinal direction (8).
5. The beam assembly of claim 4, wherein the angle of inclination (α) lies in the range between 30° and 60° and is preferably 45°.
6. The beam assembly of any of claims 3 to 5, wherein the elongated holes (34) are oriented vertically to the axis of inclination (24) of each middle-segment head plate (18).
7. The beam assembly of any of claims 1 to 6, wherein the openings (26) in the middle-segment head plates (18) are designed as elongated holes (34) and in the outer-segment head plates (20), as round holes (32).
8. The beam assembly of any of claims 1 to 7, wherein the elongated holes (34) are closed over the entire circumference.
9. The beam assembly of any of claims 1 to 8, wherein each connecting bolt (28) is designed as a threaded bolt or as a cap screw.
10. The beam assembly of any of claims 1 to 9, wherein the two head plates (18, 20) of a head-plate joint (22) are braced against each other in the final assembly state in such a manner that the lateral displaceability of the middle segment (10) is maintained under the influence of temperature.
11. The beam assembly of any of claims 1 to 10, wherein the beam (2) is a steel beam.
12. The beam assembly of any of claims 1 to 11, wherein the beam (2) is oriented vertically.
13. A structure, in particular a steel platform, having a beam assembly of any of claims 1 to 12.

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