Classifications

• • E—FIXED CONSTRUCTIONS
  • E04—BUILDING
  • E04G—SCAFFOLDING; FORMS; SHUTTERING; BUILDING IMPLEMENTS OR AIDS, OR THEIR USE; HANDLING BUILDING MATERIALS ON THE SITE; REPAIRING, BREAKING-UP OR OTHER WORK ON EXISTING BUILDINGS
  • E04G23/00—Working measures on existing buildings
  • E04G23/02—Repairing, e.g. filling cracks; Restoring; Altering; Enlarging
  • E04G23/0218—Increasing or restoring the load-bearing capacity of building construction elements

Definitions

• the invention relates to a device for reducing the deflection of a component exposed to a load, in particular the longitudinal rib in a condensation tower of a nuclear power plant, the deflection occurring transversely to the longitudinal axis of the component, with a spacer.
• the invention further relates to a method for reducing the deflection of a component exposed to a load, in particular the longitudinal rib in a condensation tower of a nuclear power plant, the deflection occurring transversely to the longitudinal axis of the component, and the component being supported such that the component is at a distance from one another a support structure is kept largely constant.
• the invention relates to a spacer for reducing the deflection of a component exposed to a load, in particular the longitudinal rib in a condensation tower of a nuclear power plant, the deflection occurring transversely to the longitudinal axis of the component.
• a method for lifting bridge and ceiling girders in the middle of the field is known from German patent specification 803 243.
• This procedure during the installation of a bridge or ceiling, i.e. Before applying a downward load, bend the bridge or ceiling upwards. The deflection is generated in that a tensile stress directed towards another structure is generated on the upper side of the bridge or ceiling, while on the lower side of the bridge or ceiling
• Bridge or ceiling over a spacer (pressure piece) with related to the other structure is, for example, a different bridge or a different ceiling.
• German patent application DE 1 959 868 describes an assembly method for beams and a device for bracing a beam.
• the beam is subjected to bending within its elastic range before it is loaded.
• This default deflection is created by tie rods that engage the bottom of the beam and create a deflection that, like the deflection under load, is directed downward.
• the bar is supported on its upper side via a stop element on a surrounding structure. Due to the preset deflection, the change in the deflection caused by a load is less than with a beam without a preset deflection.
• a disadvantage of the assembly method of DE 1 959 868 is that the area of elasticity of the beam must be sufficiently large to be able to carry out the pre-bending.
• a condensation tower also known as a barbota tower
• Water supplies are arranged in sheet metal chambers on several floors.
• the sheet metal chambers are formed, among other things, by a base sheet and a cover sheet, which are supported by parallel longitudinal ribs.
• the longitudinal ribs in turn are fastened at both ends to double T-beams which run perpendicular to the longitudinal ribs and form the basic structure of the condensation tower.
• the sheet metal chambers are designed for a certain pressure prevailing inside.
• the cover plates with the associated longitudinal ribs can now be bent in an impermissible manner. The deflection reaches its maximum value approximately in the middle of the longitudinal ribs.
• the invention is based on the object of specifying a device which reduces the deflection of a component on which a loading force acts and which is in particular a longitudinal rib - carrying a cover plate - and in this way increases the stability of the component.
• a procedure is also to be specified for the same purpose. Both the method and the device should do without pre-bending.
• the object relating to the device is achieved according to the invention in a device of the type mentioned at the outset in that the spacer acts on an end face of the component, the distance between the point of attack and a support structure being largely constant by the spacer under load is durable, and that the point of attack on the end face lies with respect to the neutral fiber on one side on which the component undergoes longitudinal expansion when it is bent.
• the point of attack should in particular be located off-center (eccentrically) on the end face.
• the increase in the stability of the component is therefore not achieved by an improvement in the material properties, such as, for example, the bending strength, but rather in that a constraint is maintained by the spacer on at least one end face of the component.
• the Wir- The described device therefore only unfolds when the component is installed, ie when a support structure is present.
• the neutral fiber is not subject to stretching or compression during deflection.
• the arrangement of the point of attack outside the neutral fiber means that the spacer, in particular by a longitudinal support force, advantageously exerts an additional bending moment on the component which counteracts the bending moment caused by the force which causes the deflection.
• the additional bending moment reduces the overall deflection.
• a bent component is compressed on one side of the neutral fiber and stretched on the other side.
• the compression leads to compressive stress and the expansion leads to tensile stress in the component.
• the stretch is counteracted in a simple manner in that a pressure is exerted on the end face by the spacer.
• the spacer loaded under pressure can therefore advantageously be mounted by clamping or plugging in between the component and the support structure, without a connection withstanding the pressure, e.g. a welded connection between the spacer and the component and between the spacer and the support structure would be necessary.
• the spacer is therefore simple and quick to assemble.
• the force that loads the component can be both a transverse load force that occurs transversely to the longitudinal axis of the component and also a longitudinal load force that also leads to bending or kinking of the component.
• the device described can advantageously improve the stability of the component without additional stabilizing elements being necessary on the long side or on the long sides of the component.
• a particular advantage of the device is that the improvement in stability is achieved by acting on the end face of the component.
• the long sides are not accessible, they have to be kept free, or they are already provided with holding elements at the accessible points that support the component whose deflection is to be reduced.
• the support structure can preferably be a neighboring component of the component type.
• the longitudinal ribs belonging to two adjacent sheet metal chambers are arranged along a common imaginary axis. At the point where they are attached to a common double T-beam, there is a gap between the two longitudinal ribs. In this
• Trap is e.g. the spacer is arranged in the gap and then engages the end faces of both longitudinal ribs.
• a longitudinal support force can be exerted approximately parallel to the longitudinal axis of the component on the point of attack by the spacer, at least under the action of the loading force.
• the longitudinal support force is a constraining force by which the component is held at a constant distance from the support structure at the point of attack.
• Boundary conditions for the deflection of the component changes that the maximum deflection is reduced with the same loading force.
• the spacer preferably comprises two end pieces, which are connected or connected via a threaded rod, and thus can be locked to an adjustable, constant minimum distance.
• a minimum distance is e.g. given when the component is not bent.
• a device designed in this way has the advantage that it can be quickly adapted to various predetermined minimum distances or distances between the component and the support structure.
• the spacer can be inserted into the component and / or into the support structure.
• the spacer can also be clamped. These configurations are particularly suitable for a spacer loaded under pressure. By inserting or clamping, e.g. In the provided recesses in the component and / or in the support structure, complex welded connections are avoided, and the spacer can be easily removed again.
• the object of specifying a method for reducing the deflection of a loaded component is achieved according to the invention in the method of the type mentioned at the outset in that the distance between a point on an end face of the component and the support structure is kept largely constant, and in that the point on the end face with respect to the neutral fiber of the component is selected on a side on which the component undergoes longitudinal expansion when it is bent.
• a spacer is preferably used for the support, the support being carried out by turning a screw nut on a threaded rod of the spacer.
• the device-related object is also achieved according to the invention in a spacer of the type mentioned in that the spacer has two end pieces which are connected via a threaded rod and can thus be locked to an adjustable constant minimum distance.
• the spacer is preferably configured such that it can be inserted or clamped into the component and / or into a support structure.
• the spacer is preferably used to carry out the method according to the invention.
• FIG. 2 shows a component exposed to a force with a device according to the invention, comprising a spacer
• FIG. 3 shows a detail from FIG. 2, in which the spacer according to the invention is shown in detail.
• FIG. 1 shows an elongated component 1, which is attached at its two ends to a support 3, which is indicated by a weld connection 2.
• Component 1 is a longitudinal rib in a condensation tower of an eastern type nuclear power plant. The longitudinal rib serves to support an overlying chamber-forming sheet (not shown). The interior of the water-filled, pressurized sheet metal chamber, of which only the lower part is shown without side walls and without sheet metal, is denoted by 5.
• the carrier 3 together with other carriers, not shown, form the basic structure of the condensation tower.
• a load-bearing force 9 acts on the component 1 perpendicular to the longitudinal axis 7 of the component 1.
• the load-bearing force 9 directed from top to bottom is caused by the pressure caused by the water on all sides within the sheet metal chamber 5 and therefore does not only act punctually - ell to component 1, but distributed over its entire length.
• the component 1 is bent transversely to its longitudinal axis 7.
• the deflection 13 is indicated schematically and exaggerated in the lower part of FIG. 1, the component 1 being represented by two lines, the upper one representing the unloaded component and the lower one the deflected component (course of the deflection w).
• the deflection w reaches its maximum value w 0 approximately in the middle of the component 1.
• a neutral line 11 generally refers to a line or surface in a component 1, which does not experience any elongation or compression in the longitudinal direction when it is bent.
• the neutral fiber 11 can lie off-center in the longitudinal section, as can be seen from FIG. 1.
• Figure 2 shows the component 1 and the carrier 3 as in Figure 1, but with the difference that a spacer 21 engages the two end faces 23 of the component 1.
• Each spacer 21 is supported on a support structure 24 on the side facing away from the component 1.
• the deflection w is reduced compared to the case shown in FIG. 1 with an equally large load force 9.
• the deflection w reaches its maximum value w A approximately in the middle of the component 1. In particular, this maximum value w A is compared to the case reduced, in which no spacer 21 acts on component 1 (w A ⁇ w 0 ).
• the section marked in a circle in FIG. 2 is shown in more detail in FIG. 3, but without the loading force 9 acting on the component 1.
• the load force 9 acts, as shown in FIG. 2, the end face 23 of the component 1 would change its position. This is also a consequence of the limited torsional rigidity of the beam 3.
• no spacer 21 were attached, underneath the neutral fiber 11, i.e. on the side facing away from the load force 9 with respect to the neutral fiber 11, move the end face 23 in the direction of the support structure 24 as a result of the bending and / or longitudinal expansion that occurs. Above the neutral fiber 11, it would move slightly away from the support structure 24 due to the deflection and / or longitudinal compression that occurs.
• the support structure 24 is a neighboring component of the type of component 1, to which — in the event of a load due to the pressure in the interior of the sheet metal chamber 5 — likewise acts a loading force (not shown) from above.
• the support structure 24 is also connected to the carrier 3 in a welded connection 2.
• the end face 25 of the support structure 24 facing the component 1 would therefore change its position in the same way as the end face 23 of the component 1 when a load is applied.
• the spacer 21 counteracts the resultant movement of the end faces 23, 25 of the component 1 or the support structure 24.
• the spacer 21 therefore engages on the end face 23 of the component 1 at an attack point 26 which lies below the neutral fiber 11.
• the spacer 21 engages on the end face 25 of the support structure 24 at an attack point 27 located below the neutral fiber of the support structure 24.
• the spacer 21 exerts a bending moment the component 1 and the support structure 24, which counteracts the deflection.
• the spacer 21 comprises two essentially flat end pieces 28A, 28B or end plates which are kept spatially separated from one another by means of a threaded rod 29.
• the first end piece 28A is welded to the threaded rod 29 via a welded connection 30.
• the second end piece 28B is pushed onto the threaded rod 29 in an opening in the area of the point of attack 26.
• a predeterminable minimum distance between the end pieces 28A, 28B can be set manually by means of a screw nut 31 screwed onto the threaded rod 29.
• the threaded rod 29 is passed through the opening in the second end piece 28B, and the projecting part is sunk in a cavity in the component 1.
• the screw nut 31 presses on the second end piece 28B via a washer 32.
• the spacer 21 is clamped by means of two centering pieces 40 in a respective recess in the component 1 or in the support structure 24. It can be assembled in this way without the need for welded connections between the first end piece 28A and the support structure 24 or between the second end piece 28B and the component 1.

Landscapes

• Architecture (AREA)
• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Electrochemistry (AREA)
• Mechanical Engineering (AREA)
• Civil Engineering (AREA)
• Structural Engineering (AREA)
• Clamps And Clips (AREA)
• Moulding By Coating Moulds (AREA)
• Rod-Shaped Construction Members (AREA)
• Bending Of Plates, Rods, And Pipes (AREA)
• Connection Of Plates (AREA)
• Buildings Adapted To Withstand Abnormal External Influences (AREA)
• Body Structure For Vehicles (AREA)
• Conveying And Assembling Of Building Elements In Situ (AREA)
• Devices Affording Protection Of Roads Or Walls For Sound Insulation (AREA)

Priority Applications (4)

Applications Claiming Priority (2)

Publications (1)

Family

ID=7840682

Family Applications (1)

Country Status (9)

Citations (6)

Family Cites Families (1)

• 1997
  • 1997-08-29 DE DE19737898A patent/DE19737898B4/de not_active Expired - Fee Related
• 1998
  • 1998-08-17 SK SK228-2000A patent/SK286468B6/sk not_active IP Right Cessation
  • 1998-08-17 CZ CZ20000700A patent/CZ301722B6/cs not_active IP Right Cessation
  • 1998-08-17 RU RU2000107805/03A patent/RU2209901C2/ru not_active IP Right Cessation
  • 1998-08-17 UA UA2000021066A patent/UA47532C2/uk unknown
  • 1998-08-17 HU HU0003218A patent/HU227615B1/hu not_active IP Right Cessation
  • 1998-08-17 WO PCT/DE1998/002387 patent/WO1999011889A1/de active Application Filing
• 2000
  • 2000-02-25 BG BG104195A patent/BG64010B1/bg unknown
  • 2000-02-28 FI FI20000451A patent/FI20000451A/fi unknown

Patent Citations (6)

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