Dampers for a frame structure

Abstract

Main claim: Damper for a frame structure, comprising: a frame; consisting of two columns and two beams, supports which together with the steel beams and columns form the frame structure; shear stresses due to laterally acting forces, such as wind, earthquakes and special forces, wherein these forces are in contact with the frame structure; a damper which is arranged inside the frame, is connected to the corners of the frame via four mechanical connections and exerts an elastic force on the frame structure in the direction of the reaction force.

Description

Background area

[0001] The invention relates to a frame damper for a steel frame building, designed to prevent frame failure due to critical bending loads and to limit lateral movements of the frame. Description of the relevant state of the art

[0002] Conventional frame damper systems exhibit an insufficiently coordinated response behavior in conjunction with the frame system. Depending on their design, these systems react either too softly or too stiffly to deformations, thus failing to reliably prevent the failure of the entire frame in braced buildings. In large structures such as skyscrapers, the increase in component size and mass due to growing horizontal loads, for example from wind or earthquakes, often leads to the formation of load-bearing structural elements such as shear walls. This reduces the structure's flexibility and simultaneously increases its overall weight, which negatively impacts its dynamic behavior. Consequently, there is a need to improve the response behavior and efficiency of such frame damper systems.

[0003] The underlying technology of the present disclosure relates to classic leaf spring suspension systems, as used particularly in commercial vehicles. In these systems, superimposed spring leaves made of spring steel serve to elastically absorb and transmit shear and vertical forces between axles and the vehicle frame. This functional principle forms the basis for the damper structure further developed in the present invention. Overview

[0004] Leaf spring suspension technology has been used in numerous vehicles and trucks, with the combination of different material properties to absorb thrust forces ensuring stability and flexibility within the support system.

[0005] A frame structure according to the present disclosure can comprise a steel or reinforced concrete structure subjected to shear and bending stresses, wherein four leaf spring assemblies are arranged on each of the four sides of the frame and coupled to the hinge areas of the frame via four mechanical connections. A core element made of reinforced concrete materials, arranged inside the frame, is positioned to absorb the forces occurring in the system.

[0006] The damper can form a cover that closes an open frame within the frame and include an elastic section made of leaf spring assemblies. The elastic section is designed such that a first side of the leaf spring assemblies is attached to connections of the damper mounts, while a second, curved side of the leaf spring assemblies rotatably surrounds an elliptical cylinder in the center of the frame. The elastic section of the leaf spring assemblies is in contact with the outer surface of the cylinder and elastically presses it towards the central frame. The elastic leaf springs include a deformation zone designed such that a first side is supported around a mounting bolt, while a second side of the deformation zone surrounds the cylinder and elastically presses against it according to the deformation caused by lateral vibrations of the frame.

[0007] The stacked leaf springs, forming a leaf spring assembly, can be designed such that the longest leaf spring is coupled to the damper mounts on both sides via mounting bolts. The damper mounts, in turn, can be mechanically or welded to the frame supports. This allows the vibration and thrust forces introduced by the frame to be absorbed elastically by the overall deformation of the leaf springs and transmitted via the cylinder.

[0008] The seating surfaces of the leaf spring packs around the cylinder can be designed in such a way that the outer surface of the cylinder is placed against the leaf springs at the contact points and pressed elastically.

[0009] Each leaf spring assembly consists of several stacked leaves, which can be made of spring steel or reinforced with carbon fibers. A total of four leaf spring assemblies are provided, coupled together via mounting bolts. While the shorter leaves are located on the outer surface of the cylinder, the longest leaves are connected to the damper mounts via the bolts.

[0010] When vibration occurs due to lateral forces acting on the building, the leaf springs arranged in the frame are pushed upwards by the cylinder and elastically deflected. This deflection creates elastic bending stresses in the spring leaves, while frictional forces arise between the individual leaves due to their relative movement, resulting in a damping effect. As soon as the vibration of the entire system subsides, the spring leaves return to their original shape after the force is released. Simultaneously, the frame returns to its original position due to the action of the damper, so that its shape remains unchanged after the vibration has subsided.

[0011] The cylinder can be designed as a non-deformable component within the damper and have a special geometric shape designed so that the cylinder is not deformed by the pressure stresses introduced by the leaf spring packs.

[0012] The cylinder is located in the central area of ​​the frame and is designed so that its outer surface is elastically subjected to compressive stresses from four leaf spring packs from four directions - top, bottom, right and left. Brief description of the drawings Fig. Figure 1 is a perspective view that schematically illustrates a frame system with dampers for a steel structure according to an embodiment of the present disclosure. Fig. Figure 2 is a composite perspective view that schematically illustrates the damper device for a steel frame according to an embodiment of the present disclosure. Fig. Figure 3 is a perspective view that schematically illustrates a damper according to an embodiment of the present disclosure. Fig. Figure 4 is a composite perspective view that schematically illustrates the damper according to one embodiment of the present disclosure. Fig. Figure 5 is a perspective view that schematically illustrates the main design of the damper device for a frame according to an embodiment of the present disclosure. Fig. Figure 6 is a side view that schematically illustrates the main design of the damper device for the frame according to one embodiment of the present disclosure. Fig. Figure 7 is a perspective view that schematically illustrates the connection of the leaf spring suspension of the damper device for the frame according to an embodiment of the present disclosure. Fig. Figure 8 is a side view that schematically illustrates the connection of the leaf spring suspension of the damper device for the frame according to an embodiment of the present disclosure. Fig. Figure 9 is a perspective view that schematically illustrates the connection of the damper device to the frame according to an embodiment of the present disclosure. Fig. Figure 10 is a perspective view that schematically illustrates the functioning of the main design of the damper device for the frame according to an embodiment of the present disclosure. Detailed description

[0013] A damping device for a frame according to embodiments of the present disclosure is described below with reference to the accompanying drawings. In this process, the thickness of the lines or the size of the components shown in the drawings may be exaggerated for the sake of clarity and simplicity.

[0014] Furthermore, the terms described below have been defined taking into account their functions in this disclosure and may be modified according to the intention or practice of a user or operator. Accordingly, such terms should be defined based on the overall content of this description.

[0015] Fig. Figure 1 is a perspective view that schematically illustrates a frame system with dampers for a steel structure according to an embodiment of the present disclosure. Fig. 2 is a composite perspective view that schematically illustrates the damper device for a steel frame according to an embodiment of the present disclosure, Fig. Figure 3 is a perspective view that schematically illustrates a damper according to an embodiment of the present disclosure, Fig. Figure 4 is a composite perspective view that schematically illustrates the damper according to an embodiment of the present disclosure. Fig. Figure 5 is a perspective view that schematically illustrates the main design of the damper device for a frame according to an embodiment of the present disclosure. Fig. 6 is a side view which schematically illustrates the main design of the damper device for the frame according to an embodiment of the present disclosure, Fig. Figure 7 is a perspective view that schematically illustrates the connection of the leaf spring suspension of the damper device for the frame according to an embodiment of the present disclosure, Fig. Figure 8 is a side view that schematically illustrates the connection of the leaf spring suspension of the damper device for the frame according to an embodiment of the present disclosure, Fig. Figure 9 is a perspective view that schematically illustrates the connection of the damper device to the frame according to an embodiment of the present disclosure. Fig. Figure 10 is a perspective view that schematically illustrates the operation of the main configuration of the damper device for the frame according to an embodiment of the present disclosure.

[0016] With reference to the Fig. 1 to 10, the damping device for the steel frame according to one embodiment of the present disclosure can comprise the column base plates 100, frame structures 200, beam-column connections 300 and dampers 400.

[0017] Two steel columns 220, two steel beams 230 with the welded beam-column connection 300, and the damper 400 can be installed in an interior space of the frame structure 210. The damper 400 is designed so that it is located after the welded beam-column connection 300 in the interior space of the frame structure 210 ( Fig. 2] can be mounted.

[0018] The damper bracket 410 can be welded or bolted to the frame 210 from four sides (In Fig. (1 to 10 are the damper mounts 400 welded to the frame support structure 210) .

[0019] Each damper holder 410 has two opposing pairs of holes in the two side plates through which the spring eye 432 (the ring-shaped curved end loop of the uppermost spring leaf 431) can be connected to a fastening bolt 420.

[0020] A leaf spring pack 430 can be connected with the screw connection 450 ( Fig. 3], which consist of a heart bolt 451 ( Fig. 7 and Fig. 8], two washers (one large 452 and one small 453] and a nut 454, are clamped.

[0021] The feather combs 440 ( Fig. 3] are attached laterally to the spring assembly. The clamps 440 enclose the entire leaf assembly 430 and hold the leaves together vertically without impeding the spring movement (bending). The clamps 440 are then screwed in place.

[0022] The elliptical cylinder forms the core element 460 of the damper system, since all design measures (housing, guide, damping devices) are designed for its function as the main load and motion transmission point.

[0023] The core element 460 consists of three components: the steel shell 470, the reinforcement 480 and the concrete 490 ( Fig. 4]. These work together as a central unit for force transmission, guidance and pressure control in the damper system 400 .

[0024] In core element 460, the outer steel shell 470 already consists of a closed tube or casing 470 that completely encloses the concrete 490. The casing 470 rests on the outside of the reinforcement 480. The reinforcement 480 is located inside the concrete 490, and there is no direct metallic connection between these two layers.

[0025] The leaf spring assemblies 430 exert local forces at the midpoint of their length only at the contact points (without additional mechanical connection) with the outer surface of the steel shell 470. The leaf spring assemblies 430 transfer the forces annularly (axially) into the steel shell 470 of the core element 460. The steel shell 470 then transmits the forces radially and axially into the concrete core 490. This prevents local stress concentrations.

[0026] The steel casing 470 acts externally like a tension ring and forms an optimized tension surface around the core concrete 490 (right side of Fig. 4] . The leaf spring assemblies 430 compress the steel jacket 470 radially and axially. Subsequently, the steel jacket 470 prevents spalling of the concrete surface due to the reaction forces, distributes the externally applied forces of the leaf springs in a ring-shaped manner, and transfers the axial compressive forces and shear stresses evenly into the concrete core.

[0027] The reinforcement 480 acts like a pressure vessel for stress distribution, but is embedded in the concrete 490 and prevents the failure of the concrete 490 as a result of tensile stresses.

[0028] The reinforcement 480 can be designed such that an outer elliptical steel shell 481 ( Fig. 4] and an inner ring-shaped steel shell 483 together with several pairs of steel tubes 482 along the circumference of the circle are joined together by welding.

[0029] The reinforcement 480 and the steel casing 470 interact only via the concrete 490. The force transfer from the steel casing 470 occurs continuously through the cross-section of the concrete 490. The reinforcement 480 acts within the concrete 490 and has a direct influence on increasing its strength.

[0030] A frame has a rectangular geometry when at rest; when a horizontal force is applied, the frame's nodes shift laterally. This leads to shear distortion, causing the frame to become parallelogram-shaped rather than rectangular.

[0031] This change in shape is a shear deformation of the frame. It occurs because the displacements between beams and supports (nodes) are not perfectly rigid, but can absorb bending moments and rotate slightly.

[0032] During the vibration process, the damper 400 acts as a stiffening element of the frame 210 against the parallelogram-like deformation.

[0033] The slight reduction in the clear height and width of the frame 210 activates the damper 400, as the horizontal forces ( Fig. 10] elicit a reaction to the rest state of the damper 400.

[0034] In a first phase, the forces introduced by the frame deformation are transferred via the damper holders 410 to the core element 460 and there converted into compressive forces in the opposite direction to the leaf spring packs 430.

[0035] In the second phase, deformations occur in the leaf spring assemblies 430, along with reaction forces resulting from the bending of the individual spring leaves under the load introduced by the core element 460. Each leaf spring assembly 430, consisting of several superimposed spring leaves made of spring steel, behaves mechanically like an elastic bending spring. Simultaneously, the individual leaves slide slightly against each other, generating friction that provides additional damping and causes hysterical behavior of the system.

[0036] The damper 400 then returns the entire frame system 200 to its original position by means of the restoring force generated in the core element 460 as soon as the vibration effect subsides, since the deformation is in the elastic range and is therefore reversible.

[0037] Although the specific embodiments of the present disclosure have been described so far, the meaning and scope of the present disclosure are not limited to the specific embodiments and can be corrected and modified in various ways by a person skilled in the art who is active in the field to which the present disclosure relates, without thereby changing the core of the present disclosure claimed in the claims.

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