WO2016072840A1

WO2016072840A1 - Rotary rubber brace damper

Info

Publication number: WO2016072840A1
Application number: PCT/MY2015/050138
Authority: WO
Inventors: Meldi SUHATRIL; Amir Fateh; Huzaifa BIN HASHIM; Mohammad Hossein MEHRABI; Hamed KHATIBI
Original assignee: Universiti Malaya
Priority date: 2014-11-06
Filing date: 2015-11-06
Publication date: 2016-05-12
Also published as: MY178721A

Abstract

The present invention discloses a damper (1) comprises: a plurality of rigid plates (2), each having a leg member (3) protruding from its periphery; and a plurality of elastic members (4); characterised in that the rigid plates (2) and the elastic members (4) are stacked alternately to form a cylindrical structure, and the different leg members (3) extend from the circumference of the cylindrical structure in a number of different directions.

Description

ROTARY RUBBER BRACE DAMPER

FIELD OF INVENTION The invention relates to a vibration damping apparatus. More particularly, the invention relates to an apparatus for dissipating mechanical energy of a frame structure such as a steel tower, a tall building, a horizontal panel, and floor.

BACKGROUND OF THE INVENTION

There are a few patented technologies over the prior art relating to the vibration- damping system. Of interest in respect to a vibration-damping floor device is US4805359A. The patent discloses a floor vibration-damping device comprising a movable support portion for supporting respective support points of a floor structure and a spring damper portion disposed between said floor structure and a fixed floor, said movable support portion comprising a lower ball receiving steel plate disposed on said fixed portion, a bearing ball disposed on said lower steel plate and an upper ball receiving steel plate secured to said floor structure and placed on said bearing ball, said spring damper portion comprising a damper main body of a shallow and flat vessel shape mounted on and secured to said fixed floor a viscous fluid contained by a predetermined amount in said damper main body, a movable member attached to said floor structure, immersed in said viscous fluid and ensuring a predetermined gap between a lower surface of said movable member and a bottom of said damper main body, a coil spring secured to said fixed floor at one end thereof, a rope-like member not transmitting a compressive force and being connected to the other end of said coil spring at one end thereof and connected to said movable member at the other end thereof, and a reaction force receiving roller attached to said rope-like member and abutted against an inner surface of said damper main body. Another vibration damping apparatus is disclosed in US4545466A. The patent provides a vibration damping apparatus comprising at least two rotatable members disposed opposite to each other while defining a gap therebetween so as to be rotatable relative to each other around substantially a single axis of rotation, four link bars pivoted to each other at their both ends by pins so as to constitute a quadric crank mechanism capable of turning around the axes of the pins, and a resistive body disposed in the gap between said rotatable members, the two link bars disposed opposite to each other among said four link bars being coupled at their middle points to the corresponding points of one of said rotatable members respectively, which points are spaced apart by the same distance from the axis of rotation of said rotatable member, the remaining two link bars disposed opposite to each other being coupled at their middle points to the corresponding points of the other of said rotatable members respectively, which points are spaced apart by the same distance from the axis of rotation of said the other rotatable member.

Although visco-elastic dampers are proven to be effective in suppressing structural motions, the overall lateral stiffness of the structure under dynamic loads is reduced. Therefore, a need exist for the prior apparatus to replace visco-elastic material with natural rubber for a better damping efficiency and improvement in lateral stiffness. This invention provides such an apparatus.

SUMMARY OF INVENTION

The invention provides a damper comprises a plurality of rigid plates, each having a leg member protruding from its periphery, and a plurality of elastic members, characterised in that the rigid plates and the elastic members are stacked alternately to form a cylindrical structure, and the different leg members extend from the circumference of the cylindrical structure in a number of different directions. Preferably, the rigid plates are of a circular shape and the elastic members are of a cylindrical shape. The rigid plates can be made of metal material and the elastic members can be made of rubber material. In one embodiment of the invention, at least two of the leg members extend from the circumference of the cylindrical structure in a same direction and connect to a frame member. The angles formed by the leg members can be equal to each other.

At least one of the preceding objects is met, in whole or in part, by the present invention, in which the embodiment of the present invention describes an apparatus for dissipating mechanical energy of a frame structure when it is under a lateral load comprises a plurality of circular rigid plates, each having a leg member protruding from its periphery, and a plurality of cylindrical elastic members, characterised in that the circular rigid plates and the cylindrical elastic members are stacked alternately to form a cylindrical structure, and the different leg members extend from the circumference of the cylindrical structure in a number of different directions to the elements of the frame structure.

One skilled in the art will readily appreciate that the invention is well adapted to carry out the objects and obtain the ends and advantages mentioned, as well as those inherent therein. The embodiments described herein are not intended as limitations on the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

For the purpose of facilitating an understanding of the invention, there is illustrated in the accompanying drawing the preferred embodiments from an inspection of which when considered in connection with the following description, the invention, its construction and operation and many of its advantages would be readily understood and appreciated.

Figure 1 is a schematic diagram illustrating a damping apparatus which embodies therein the principle features of the invention.

Figure 2 shows a rigid member of the damping apparatus.

Figure 3 shows a cylindrical elastic member of the damping apparatus.

Figure 4 depicts the damping apparatus attached to a frame structure.

DETAILED DESCRIPTION OF THE INVENTION

The invention will now be described in greater detail, by way of example, with reference to the drawings.

Referring to figures 1 to 3, an overall view of a damper (1) illustrated therein comprises one or more circular metal plates (2), each having a rectangular elongated member (3) protruding from its circumference, and one or more cylindrical rubber shims (4), wherein the circular metal plates (2) and the cylindrical rubber shims (4) are stacked alternately to form cylindrical structure with at least two elongated members (3) extend from the circumference of the cylindrical structure in a same direction and connect to a rectangular metal plate member (5) for attachment.

Referring to figure 4, the damper (1) is preferably attached to a centre position of a top horizontal frame (6) member. The damper (1) has two pairs of the elongated members (3) extended to both bottom corners of the frame structure (6) for connection and three of the elongated members (3) extended vertically to connect with the top horizontal frame (6) member. When the frame structure (6) laterally swings due to external lateral force such as earthquake, the movements of the frame members (6) will deform the cylindrical rubber shims (4). The cylindrical rubber shims (4) with the elastic properties will return to their original shape after being deformed.

In one specific example of the invention, a finite element modelling is carried out by a ABAQUS software for evaluating the energy dissipation capability of the damper. The following table 1 shows the material properties used in the finite element modelling. The cylindrical rubber shims are defined as a hypereleastic material by the Neo Hook rule and used the ABAQUS software to test data for rubber property.

Table 1 shows the material properties used in the finite element modelling. Process of the monotonic displacement in the modelling is shown in table 2. The monotonic displacement history was subjected to top nodes of structure. After applying the monotonic analysis in 2D structure, the hysteresis curves for variety models and the maximum failure force whenever the structure subjected to cycle displacement are obtained. Comparing with bare frame, the analysis shows there is an increment in the hysteresis curve area and hence indicates that the energy dissipation capacity is enhanced. Time Displacement (mm)

0 0

0.1 0.5

0.2 -0.5

0.3 1

0.4 -1

0.5 1.5

Table 2 shows the mono tonic displacement of the damper during the modelling.

The present disclosure includes as contained in the appended claims, as well as that of the foregoing description. Although this invention has been described in its preferred form with a degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and that numerous changes in the details of construction and the combination and arrangements of parts may be resorted to without departing from the scope of the invention.

Claims

1. A damper (1) comprising:

a plurality of rigid plates (2), each having a leg member (3) protruding from its periphery; and

a plurality of elastic members (4);

characterised in that the rigid plates (2) and the elastic members (4) are stacked alternately to form a cylindrical structure, and the different leg members (3) extend from the circumference of the cylindrical structure in a number of different directions.

2. A damper (1) according to claim 1, wherein the rigid plates (2) are of a circular shape.

3. A damper (1) according to claim 1 or claim 2, wherein the rigid plates (2) are made of metal.

4. A damper (1) according to any one of claims 1 to 3, wherein the elastic members (4) are of a cylindrical shape.

5. A damper (1) according to any one of claims 1 to 4, wherein the elastic members (4) are made of rubber material.

6. A damper (1) according to any one of claims 1 to 5, wherein at least two of the leg members (3) extend from the circumference of the cylindrical structure in a same direction.

7. A damper (1) according to any one of claims 1 to 6, wherein at least one leg member (3) is connected to a frame (6) member.

8. A damper according to any one of claims 1 to 7, wherein angles formed by the leg members (3) are equal to each other.

9. An apparatus (1) for dissipating mechanical energy of a frame structure (6) when it is under a lateral load comprising:

a plurality of circular rigid plates (2), each having a leg member (3) protruding from its periphery; and

a plurality of cylindrical elastic members (4);

characterised in that the circular rigid plates (2) and the cylindrical elastic members (4) are stacked alternately to form a cylindrical structure, and the different leg members (3) extend from the circumference of the cylindrical structure in a number of different directions to the elements of the frame structure (6).