JPH11200546A - Damping slabs and structures - Google Patents

Abstract

(57) [Abstract] [Problem] To provide attenuation to a structure without being restricted by a building plan. SOLUTION: A joint 2 is formed in a part of a slab 1 in a thickness direction of the slab 1 at a depth of at least a part of a total thickness, and the joint 2 is filled with an attenuating material 3 having a damping property. Then, the slab 1 itself is given a damping function.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a damping slab having a slab itself provided with a damping function, and a damping structure including the same.

[0002]

2. Description of the Related Art Methods of imparting damping to a structure include a viscoelastic body, a brace or the like, between adjacent layers in the structure through a seismic element such as a brace, or the like. There is a method of arranging dampers etc. that cause friction, but in any case, these damping devices are incorporated in the framework of the structure and installed vertically, so it is easy to be restricted by architectural planning, and May not be practical.

[0003] Even if it is possible to install the damping device itself, for example, when using a damping device that obtains a damping effect of the entire structure by being incorporated in a fixed position for each layer, for example, it is necessary to use a building plan. If restrictions restrict the position and number of damping devices that can be incorporated, the desired damping effect cannot be obtained in the entire structure.

In view of the above background, the present invention proposes a damping structure which is not restricted by a building plan.

[0005]

According to the present invention, a joint is formed in a part of a slab in a thickness direction of the slab at a depth of at least a part of a total thickness, and the joint has a damping property. Filling the slab with in-plane deformation performance and damping performance by filling the damping material, and applying the damping performance to the slab itself enables the implementation of a damping structure regardless of building plan restrictions, Extend the scope of the application.

The joint reduces the in-plane rigidity of the slab so that the slab is easily deformed in the plane. The damping material generates a damping force when the slab is deformed in the plane, and suppresses the deformation of the slab. Reduces the vibration of the connecting skeleton. The in-plane deformation of the slab is caused by a relative horizontal deformation between both sides of the joint, and as a whole occurs as a shear deformation.

The damping material does not straddle different structural members and is incorporated in the same member, the slab, so that there is no restriction in terms of layout and architectural planning unlike conventional damping devices, Has the freedom to respond to any architectural plan.

A normal slab has a very high in-plane rigidity and a small in-plane deformation, so that a rigid floor assumption is established. For example, it is assumed that a horizontal force due to a large earthquake acts on a building structure of a square plane having two spans in each of an x direction and a y direction on a plane. In this case, because the slab has high in-plane rigidity, the plane shape moves horizontally while maintaining the square,
The shear force accompanying the horizontal deformation acts on the columns of each frame horizontally.

On the other hand, the damping slab according to claim 1 in which the joint formed on a part of the slab is filled with the damping material has a property of being easily deformed in-plane by a horizontal force. Columns and beams with damped slabs, or frames consisting of walls, are deformed by the horizontal force generated during an earthquake according to the rigidity and mass of each frame. Therefore, as shown in FIG. 4 and FIG. Deformation occurs and the damped slab undergoes shear deformation.

For example, in the structure shown in FIGS. 1 and 2, the end in the X direction of each of the plane frames constituting the plane in the X direction is determined from the ratio of the load of the slab borne by the columns of each plane frame. Columns located at positions other than the end bear more load than columns located at the end, and therefore columns other than the end are more likely to be deformed than columns at the end due to horizontal force in the Y direction.

For this reason, the damping slabs connected to the columns of the two-sided frame members facing each other in the Y direction tend to shear due to the horizontal force in the Y direction. At this time, the damping material generates a damping force according to a relative speed difference between the two portions sandwiching the damping material due to relative horizontal deformation. Reduce the vibration of the plane skeleton that constitutes.

The damping force of the damping slab generated by the horizontal force in the Y direction is, in a structure in which three or more X-direction plane frames having two or more spans are arranged in the Y direction.
It is also generated by the same mechanism by the horizontal force in the X direction.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The damping slab according to the first aspect of the present invention is shown in FIGS. The joint 2 formed is filled with the damping material 3. The slab 1 includes a floor slab, a roof slab, and a foundation slab.

For the damping material 3, for example, a polymer material such as silicon, a metal material such as aluminum or lead, or a rubber having a damping property such as a high damping rubber is used. Regardless.

The joint 2 is formed from the upper surface side or the lower surface side of the slab 1 to a part of the total thickness or to the entire thickness. FIG. 3 shows a case where the joint 2 is formed over the entire thickness of the slab 1 and the damping material 3 is filled in a plurality of layers in the width direction of the joint 2.

In the case of FIG. 3, the damping material 3 is sandwiched between separators 4 made of a harder steel material or the like, and is filled with the separator 4 bonded or joined thereto. Fig. 3- (a)
(B) is a case where the slab 1 is made of reinforced concrete, (b) is a case where the slab 1 is made of reinforced concrete integrated with a discarded formwork of the deck plate, and (c) is a case where it is made of precast concrete.

In the case of FIGS. 3 (a) and 3 (b), the joint 2 is formed by embedding a joint member in advance at the time of placing concrete, and in the case of FIG. Are connected by the damping material 3 or the damping material 3 and the separator 4.

In the drawings, the joints 2 are formed to be long in one direction and arranged at intervals in a direction intersecting the joints. However, the joints 2 are formed by deformation of a plane frame to which the slab 1 is connected by a horizontal force, as described later. It is sufficient that the slab 1 is formed in a state where the horizontal rigidity of the slab 1 is adjusted so that the slab 1 can be deformed in-plane. The depth, length, and arrangement of the joints 2 are not limited to the shapes shown in the drawings.

Due to the formation of the joint 2, the slab 1 is deformed in-plane with the deformation of the plane frame, and a relative horizontal deformation is generated between the portions on both sides of the joint 2. At this time, the damping material 3 generates a damping force according to the relative speed difference between the two parts, thereby suppressing the deformation of the slab 1 and reducing the vibration of the plane frame.

FIGS. 1 and 2 show a construction in one direction, and FIG.
The plane frame having the above span is in the span direction (X direction).
Are arranged in three rows in a direction (Y direction) intersecting with the vertical frame, and the adjacent columns 5, 5 of the plane skeleton in the X direction and the adjacent columns 5, 5 of the plane skeleton in the X direction opposed to the plane skeleton are claimed. An example of a structure to which the damping slab of item 1 is connected is shown. Here, a case is shown in which the structure has a three-layer structure in both the X and Y directions and has a two-span rigid frame structure. However, the plane frame does not necessarily need to have the rigid frame structure.

In this structure, of the three plane frames I, II, and III constituting the plane in the X direction in FIG. 1, the plane frame II located at the center in the Y direction is determined from the dominant area of the column 5 in the X direction. When a horizontal force is applied, the horizontal frames I and III bear a greater horizontal load than the planar frames I and III located on both sides, and each of the planar frames I and III on both sides bears about half the horizontal load of the central planar frame II.

Since the slab without joints 2 assumes the rigid floor assumption, a horizontal displacement occurs uniformly when a horizontal force is applied in the X direction. Therefore, the central plane frame II and the plane frames I and III on both sides thereof are Although the slab 1 of claim 1 is deformed horizontally by the same amount, the rigid floor assumption is not established due to the formation of the joints 2, the slab 1 is easily deformed in the plane, and the horizontal load of each plane frame I, II, III bears. Due to the difference in size, as shown in FIG. 4, the plane skeleton II in the center and the plane skeletons I and III on both sides show different vibration characteristics, and the deformation of the plane skeleton II is larger than the deformation of the plane skeletons I and III. Become.

At this time, a shearing force acts in the plane of the slab 1 as shown by an arrow between the portions on both sides of the joint 2 of each slab 1, and the rectangular slab 1 is caused by the shearing force.
Is sheared into a parallelogram. The damping material 3 generates a damping force according to the relative speed difference at the time of deformation, and this damping force acts on both sides of the joint 2, so that the vibration of each of the plane frames II, I, and III is Decays as it occurs.

FIG. 5 shows a state where a horizontal force in the Y direction acts. In this case as well, the situation is the same as when the horizontal force in the X direction is applied, and the plane structure is formed in the Y direction, and the plane frame V located at the center in the X direction and the plane frames IV and VI on both sides have different vibrations. do. Since a damping force is generated between the portions on both sides of the joint 2 at that time due to the shearing deformation, the vibrations of the plane frames V, IV, and VI are generated together with the generation as in the case of the horizontal force action in the X direction. Decay.

Therefore, in the drawing, the joints 2 of each slab 1 are formed to be long in the Y direction and are arranged at intervals in the X direction. However, in order to reduce the vibration of the frame, the arrangement direction of the joints 2 is horizontal. It will not be related to the direction of force application.

FIG. 6 shows a vibration model of the structure shown in FIGS. As described above, when the entire plane skeleton of the structure is divided into the center plane skeleton II forming the plane in the X direction and the plane skeletons I and III on both sides, the center plane skeleton II is divided into the plane skeleton I on both sides. , III, the mass M to be borne is also larger than the mass m, borne by the plane frames I, III,
The mass M is about twice the mass m from the relation of the dominant area of the column 5 described above.

The slab 1 connecting the plane skeleton II and the plane skeleton I and the slab 1 connecting the plane skeleton II and the plane skeleton III are easily deformed in the plane. Therefore, the plane skeleton II and the plane skeletons I and III are respectively formed. Vibrates independently of each other in accordance with the natural period, and the plane frame II and the plane frames I and III constitute different vibration systems.

Further, since the damping material 3 is interposed in the slab 1 connecting the plane skeleton II and the plane skeleton I and the slab 1 connecting the plane skeleton II and the plane skeleton III, the structure shown in FIGS. The object is a plane frame II and a plane frame I of different vibration systems
This is the same as the connection of the damping device between the frames and between the plane frames II and III, and a vibration model as shown in FIG. 6 is established.

In the vibration model shown in FIG. 6, since the plane frame I and the plane frame III are the same vibration system, both can be combined into one vibration system, and the vibration model of FIG. This is simplified to the vibration model of the two-mass system shown.

The mass M 'and the horizontal rigidity K1 of the vibration system obtained by combining the plane frame I and the plane frame III are obtained by simply doubling the mass m and the horizontal rigidity of the plane frame I shown in FIG. M ′ is substantially the same as the mass M of the plane skeleton II, and the horizontal stiffness K1 is twice the horizontal stiffness K2 of the vibration system of the plane skeleton II.

FIG. 8 shows a resonance curve of the vibration model shown in FIG. In a certain vibration model, the damping constant, which is a parameter of the resonance curve, is arbitrarily selected (for example, when the damping constant is 0 and when the damping constant is ∞). As shown, if a damping constant is set such that this intersection point becomes the maximum value, the damping constant becomes an optimum damping constant in the vibration model. From the resonance curve shown by the solid line in FIG. 8, it can be seen that h = 1/2 · {(f2-f1) / f0}
A decay constant of 10% is obtained. f1 and f2 are the resonance frequencies of the resonance curve shown by the broken lines.

[0032]

According to the first aspect of the present invention, the joints formed on a part of the slab are filled with an attenuating material having a damping property, and the slab itself is given a damping performance. Therefore, there is no restriction from the aspect, and it is possible to cope with any architectural plan and extend the range of application to structures.

According to the second aspect, the damping slab according to the first aspect is applied to a part or the whole of each floor slab of a structure having a frame including columns, beams, or walls, so that the floor slab intersects at least in the span direction. The damping slab is shear-deformed by the horizontal force in the direction, and the damping material generates a damping force according to the relative speed difference between both sides of the damping material during the deformation, so that the vibration of the structure can be effectively reduced .

[Brief description of the drawings]

FIG. 1 is a plan view showing an example of a structure to which a damping slab is applied.

FIG. 2 is a longitudinal sectional view of FIG.

FIG. 3 is a cross-sectional view showing an example of filling a slab with a damping material.

FIG. 4 is a plan view showing a state of deformation of a plane skeleton and a damping slab when a horizontal force in the X direction acts on the structure of FIG. 1;

FIG. 5 is a plan view showing a state of deformation of a planar skeleton and a damping slab when a horizontal force in a Y direction acts on the structure of FIG. 1;

FIG. 6 is a diagram modeling the structure of FIGS. 1 and 2;

FIG. 7 is a simplified diagram of the vibration model of FIG. 6;

8 is a graph showing a resonance curve obtained from the vibration model of FIG.

[Explanation of symbols]

1 ... slab, 2 ... joint, 3 ... damping material, 4 ... separator, 5 ... pillar.

Claims (2)

[Claims] Claims 1. A part of a slab, in a thickness direction of the slab,
A damping slab in which a joint is formed at least at a part of the depth of the entire thickness, and the joint is filled with a damping material having a damping property. 2. A damping structure in which a part or all of each floor slab is the damping slab according to claim 1, in a structure having a frame composed of columns, beams, or walls.