JPH10168822A - Structural elastic supporting body and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lead plug contained elastic supporting body excellent in durability as well as in base isolation by adjusting the functions of the lead plug and a high damping rubber which are in anitnomic functional relation with their capability and durability. SOLUTION: This structural elastic supporting body is composed by integrally laminating a rubber layer 21 and a reinforcement plate and providing a lead plug 23 by piercing it through the elastic body and the reinforcement plate in the axial direction with respective upper and lower fitting members integrally fitted on the top and the bottom of the elastic supporting body. In this case, the rubber layer 21 is composed of a linearity-sided high damping rubber material having the material mixed so that it may be more linearity than the nonlinearity of the normal high damping rubber and a single or a plurality of lead plugs 23 compensating the lowered damping capacity thereby caused are fitted in the center of the elastic supporting body.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an elastic bearing for a structure used for elastically movably supporting a bridge girder or other structures.

[0002]

2. Description of the Related Art An elastic bearing in which a hard plate such as a steel plate and a soft plate having a viscoelastic property such as rubber are laminated has been widely used as a bearing member which is required to have a vibration-proof property and a vibration-absorbing property. .

As a general structure of such an elastic bearing body, as shown in FIG. 5, a rubber layer 1 of soft natural rubber or high damping rubber and a plurality of thin reinforcing plates 2 are laminated and integrated. Further, one or a plurality of lead plugs 3 are provided through the rubber layer 1 and the reinforcing plate 2 to form an elastic support main body 4, and an upper mounting member 5 and a lower mounting member are provided above and below the elastic support main body 4. 6 are integrally mounted. The upper and lower ends of the lead plug 3 are inserted into plug insertion holes 7 formed in the upper and lower mounting members 5, 6, and the plug insertion holes 7 are connected to the upper and lower mounting members 5, 6 using fixing bolts 8. It is closed by the fixed lid plate 10. The upper structural member such as a bridge is mounted on the upper mounting member 5, and the lower structural member such as a pier is mounted on the lower mounting member 6.

The lead plug-containing elastic bearing body is manufactured through the steps shown in FIGS. That is, as shown in FIG. 7, a guide projection 12 for forming a plug insertion hole is erected from above a support base 12 placed on a base 11, and the plug projection hole 12 is formed on the guide projection 12 in order from the bottom. A lower mounting member 6 having a rubber layer 1;
The upper mounting member 5 having the plug insertion hole 7 is further laminated on the uppermost portion. An adjusting plate 15 is placed on the upper surface of the upper mounting member 5, an outer peripheral split mold 16 is arranged outside these, and a pressing plate 17 is placed on the adjusting plate 15 to assemble a mold. By pressing the pressing plate 17, heat and pressure are applied to the laminated rubber layer 1, and the final shape of the laminated rubber is made.

After that, the above-mentioned mold is disassembled, the elastic supporting body is released from the mold, and the lead plug 3 is pressed into the central plug through hole 14 as shown in FIG.
The lid plate 10 is mounted on the upper and lower mounting plates 5 and 6 to complete the elastic support body containing the lead plug.

The lead plug-containing elastic bearing has the following characteristics. That is, FIGS. 9 and 10 show hysteresis curves of the 1st cycle and the 2nd cycle in the vibration test of the elastic support body containing the lead plug. This test is a hysteresis loop in which a specimen, which is an elastic bearing of the type shown in FIG. 6, is forcibly pulled back at a constant vertical load and vibration rate. As can be seen particularly from the difference between the first cycle and the second cycle, it is well known that the elastic bearing body into which the lead plug is press-fitted has a predetermined damping performance due to its dynamic characteristics (history characteristics).

By the way, a laminated rubber bearing containing lead plugs (L
・ R ・ B) is the rubber material is NR material JIS K6 38
The A06 to A13 structural performance characteristics of No. 6 are damping shoes utilizing recrystallization of lead plugs. The relationship between the lead plug and the damping performance is large when the area of lead occupying the rubber bearing plane is large (for example, 4% to 12%, and the center is around 6%). When the area of lead occupying the rubber bearing plane is small (4% or less), there is a relationship that the damping performance is small. In general, the number of lead plugs in L, R, and B used for bridges is generally four, and the number of lead plugs in L, R, and B used for construction is generally one. .

The relationship between the amount of lead plugs and the durability is such that as the area and the number of lead plugs increase, the temperature inside the bearing increases due to heat storage due to thermal energy conversion due to repetitive shearing of the plastic region. Has a bad relationship. That is,
The lead plug bites into the rubber portion, the reinforcing steel plate bends and warps, and the adhesive peels off from the rubber and the lead plug itself is damaged. For example, the shear deformation rate γ ± 100% to 150% to 2
By continuous repetition of 00% N = 50 to 100 times,
Damage from the lead plug itself is inevitable. More specifically, in FIG. 11 to FIG. 17, a rubber layer 1 and a plurality of thin reinforcing plates 2 are laminated and integrated, and a plurality of Lead plugs 3 are provided therethrough, and the upper and lower mounting members 5,
6 shows an example in which an elastic bearing is configured by being attached. When vibration is applied to the elastic bearing in the vibration direction of the horizontal arrow, the upper portion of the elastic bearing repeats rightward movement shown in FIGS. 13 and 14 and leftward movement shown in FIGS. It comes to rest in the initial state of FIGS. In this case, γ = ± 100% to 150% to 200%, N = 5
0 to 100 times.

When the horizontal vibration is applied to the lead plug-containing elastic bearing body, the shearing is repeated, so that the force is constantly transmitted at the boundary between the lead plug, the reinforcing steel plate and the rubber portion. For this reason, as shown in FIG. 17 (c), the reinforcing plate portion (part B in FIG. 13) which is not divided by the lead plug through hole 14 in the vibration direction has no damage, whereas FIG.
As shown in (A) and (B), a portion (a portion in FIG. 13) divided by the lead plug through hole 14, that is, a reinforcing plate end portion 18, has a warp, a rubber cut around the through hole, and a part thereof. Peeling or the like occurs, and a part of the location is close to a location where a stress of about twice the average stress is generated due to a bearing mechanism of a rubber bearing, which causes a problem in terms of long-term durability deterioration.

[0010] That is, the seismic isolation rubber bearing (L, R, B) containing the lead plug has the upper and lower limit performance values of the amount of the lead plug in the rubber bearing, that is, the diameter of the lead plug. The number corresponds to the design, such as bilinear characteristics, compound force, and energy absorption capability. The characteristic values (particularly, damping function and equivalent steel properties) depend on the deformation of the plastic region due to the recrystallization property of lead. Although durability is obtained by repetition, heat energy conversion by inevitably raising the temperature inside the elastic bearing body is inevitable due to conversion of thermal energy by the number of repetitions, and its performance characteristics are inconsistent with its performance characteristics.

Also, a plurality of lead plugs (generally four)
A seismic isolation shoe designed and manufactured for use is liable to suffer positional damage on a durable surface due to repeated deformation, as easily imagined from the planar structure shown in FIG.

In view of the above-mentioned damage tendency, it is originally desirable that the number of lead plugs be one at the center in order to slightly increase the durability (however, in consideration of the number of leads, the lead diameter and height are not preferable). Then, there is also a constraint that 1.25 ≦ Hp / D ≦ 5.
p is height (total thickness of rubber) D is diameter of lead). LR
As for the performance characteristics of B, the total amount of lead plugs is dominant from the damping characteristics, and the number of lead plugs is 4 for bridge use.
Books must be mainstream.

[0013]

In view of the various problems as described above, the conventional elastic bearing with a lead plug has a structure in which the performance characteristics of lead are minimized, The amount of plug used is 1/2 to 1/3 of the conventional amount.
An object of the present invention is to provide an elastic bearing for a structure, which has a structure for preventing a reduction in proof stress due to repetition of a reinforcing plate in a peripheral portion, and in which the above-mentioned disadvantages are improved.

[0014]

According to the present invention, a rubber layer and a reinforcing plate are laminated and integrated, and a lead plug is provided through the elastic body and the reinforcing plate in the axial direction. In a structural elastic support body in which a main body is configured and upper and lower mounting members are integrally mounted on upper and lower sides of the elastic support main body, respectively, the rubber layer is more linear than normal non-linearity of high damping rubber. It is composed of a high-damping rubber material blended with a material (molecular design), and a lead plug, which compensates for a slight decrease in damping performance due to it, is inserted into the center of the elastic support body in principle. . Further, in the method for manufacturing an elastic bearing for a structure according to the present invention, a lead plug is erected on an upper surface of a lower mounting member placed on a support base, and each of the lead plugs has a plug insertion hole, A high-damping rubber material blended with a material (molecular design) and a reinforcing plate are alternately laminated so as to be closer to the linearity than the nonlinearity of a normal high-damping rubber, and press-fit into the lead plug through a small gap. Then, the upper part of the lead plug protruding from the upper part of the laminate is brought into contact with the lower surface of the upper mounting member to form a gap L between the upper surface of the laminate and the lower surface of the upper mounting member. The method is characterized in that the linear plugged high damping rubber material is heated and pressurized and vulcanized while pressurizing the lead plug in the axial direction via the mounting member.

According to the present invention, in a lead plug-containing elastic bearing, the non-linearity of the conventional ordinary high-damping rubber and its disadvantages are improved by the high-damping rubber material closer to linearity.
In addition, since lead plugs are used to compensate for the decrease in damping performance due to this configuration, the characteristics of high-damping rubber and lead plugs, which are essentially trade-offs between performance and durability, are harmonized and utilized. It provides the most ideal seismic isolation function of a lead-plugged elastic bearing with excellent damping and durability.

Further, according to the method of manufacturing an elastic bearing for a structure of the present invention, after vulcanization of the rubber bearing, pressurization and contact in the manufacturing process can be performed without press-fitting a lead plug in a conventional post-process. Can be achieved. In addition, this support functions as a composite shoe with a lead plug bearing and rubber material (molecular design), and does not require a lead plug lid due to shrinkage strain (generally, a flanged lid is required, Arbitrary design of the level of the damping constant as a damping shoe is also easy.

[0017]

Embodiments of the present invention will be described below. In the present invention, the rubber material of the elastic support body containing the lead plug is made of natural rubber as a substrate, using a molecularly designed high-damping rubber material, and considering the durability, the nonlinear performance of the high-damping rubber is slightly more linear. A high-damping rubber compound is used, and the damping performance is slightly reduced by that amount. However, one or two lead plugs are designed to fit in the center of the elastic bearing to compensate for the reduced amount, and at a predetermined shear deformation rate Is based on the idea of securing a damping constant value as a damping shoe.

As a result, the disadvantages of a pure high damping rubber material (having a large hysteresis loss, inevitably a large residual strain in the shear direction, and a poor durability in comparison with a natural rubber material) are improved. The functional performance (damping constant) of the lead plug is enhanced by the lead plug, and the area occupied by the lead of the elastic support containing the lead plug is reduced to な い し or ３. As with the high damping rubber bearing, the elastic support containing the lead plug is used. There is a trade off between the damping effect and the durability of the body lead, but by reducing the amount of lead plug used, the effect of increasing the durability performance is higher than the elastic support body with lead plug only, like the high damping rubber sole shoe. Be expected.

Further, according to the present invention, based on the above-described structure, as a composite shoe made of a lead plug and rubber, a composite shoe completed with a lead plug inserted at the time of manufacturing a rubber bearing (highly damped with a molecular design closer to linearity) Rubber material is used and lead plugs are included from the beginning). On the other hand, the conventional elastic support with lead plug is usually inserted with lead plug (press fit).
For this purpose, as described in the conventional example, a lead plug prepared in advance into a hole (core portion) having a lead plug diameter plus a small amount of margin in advance is press-fitted in a later step. In other words, a predetermined vertical force is applied to the lead plug in order to fill the concave portion caused by the contraction of the core rubber portion with lead, and the outer diameter is elastically or plastically deformed due to the stress distortion (stress and elongation) characteristics of lead. The purpose of this is to adjust the deformation speed, so that the lead plug adheres to the periphery of the rubber hole by transition creep. Therefore, in this lead plug press-fitting method, the press-fitting process is complicated, the structure is complicated, and it is difficult to set a desired value of the damping constant.

In contrast, the present invention is configured as follows. Referring to FIGS. 1 to 5, a rubber layer 21 of a highly linear damping rubber and a plurality of thin reinforcing plates 22 will be described.
And the rubber layer 21 and the reinforcing plate 22
And one or a plurality of lead plugs 23 are provided to form an elastic support main body 24.
The upper mounting member 25 and the lower mounting member 26 are integrally mounted on the upper and lower sides. Upper and lower mounting members 25,
The upper and lower ends of the lead plug 23 are fitted into and fixed to the plug fitting concave portions 27 formed on the inner side surface of the plug 26. Also,
An upper structure such as a bridge is mounted on the upper mounting member 25, and a lower structure such as a pier is mounted on the lower mounting member 26.

The lead plug-containing elastic bearing body is manufactured through the steps shown in FIGS. That is, as shown in FIG. 2, the lower mounting member 26 is mounted on the support base 12 mounted on the base 11, and the lower end of the lead plug 23 is fitted and fixed in the plug fitting concave portion 27 at the center of the inner surface. Have been. Next, a plurality of rubber layers 21 of high-attenuation rubber and a thin steel plate 22 are alternately laminated while the respective plug through holes 28 are fitted to the lead plugs 23. At this time, the inner diameter of the plug through hole 28 of each of the rubber layer 21 and the reinforcing plate 22 is slightly larger than the outer diameter of the lead plug 23, and a small gap 29 is formed between the two.
3 so that the rubber layer 21 and the reinforcing plate 22 can be easily fitted to each other.

After the rubber layer 21 and the reinforcing plate 22 have been completely stacked, the upper end of the lead plug 23 projecting from the upper portion is fitted into the plug fitting recess 27 on the lower surface of the upper mounting member 25 and fixed. At this time, an L gap is formed between the uppermost rubber layer 21 and the upper attachment member 25.

Next, as shown in FIG.
An adjusting plate 15 is placed on the upper surface of the device 5, and an outer peripheral split mold 16 is disposed outside the adjusting plate 15. By pressing the adjusting plate 15 with a pressing plate 17, heat and pressure are applied to the laminated rubber layer 21. Hang it to make the final shape of the laminated rubber. By pressing with the pressing plate 17, the lead plug 23 is compressed in the axial direction corresponding to the L gap between the uppermost rubber layer 21 and the upper mounting member 25, and its diameter increases, so that the outer periphery of the lead plug 23 The rubber layer 21 and the inner peripheral surface of the plug through hole 28 of the reinforcing plate 22 are in close contact with each other, and the gap 29 between them is eliminated.

After that, the mold is disassembled, and the elastic support is removed from the mold to complete the lead plug-containing elastic support.

According to the above method, after vulcanization of the rubber bearing, the labor saving of the process can be achieved by omitting the press-fitting of the lead plug as in the prior art, and the ductility (ductility) of the lead by the press-fitting of the lead plug is reduced to the minimum pressure t. , A natural stress strain can be generated and adhesion can be achieved. In addition, as a lead-containing composite shoe with a lead-integrated structure directly under the shear, there is no need for a lid for the lead plug after the lead plug is inserted (generally, a flanged lid is required, and the lid is fixed with a countersunk screw). The magnitude of the damping constant of the damping shoe can be arbitrarily designed.

Further, due to the synergistic effect of the lead plug and the linearly high-damping rubber, the rigidity in the small shear deformation region is utilized as it is, and the trigger mechanism is reproduced.

[0027]

As described above, according to the present invention, in the elastic support body containing lead plugs, the nonlinearity of the conventional ordinary high damping rubber and its disadvantages are improved by the linear damping high damping rubber material. In addition, since lead plugs are used to compensate for the decrease in damping performance due to this configuration, the characteristics of high-damping rubber and lead plugs, which originally have a trade-off relationship between performance and durability, are harmonized. Therefore, there is an effect that an elastic bearing body containing a lead plug having excellent damping properties and durability can be obtained. Furthermore, according to the manufacturing method of the lead plug-containing elastic bearing body of the present invention, in addition to the above-described effects, labor saving by eliminating the need for press-fitting of the lead plug,
There is an effect that it is possible to easily design a large and small damping constant with close integration with the laminated rubber.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a lead plug-containing elastic bearing according to an embodiment of the present invention.

FIG. 2 is a first process diagram of manufacturing the lead plug-containing elastic bearing body of FIG. 1;

FIG. 3 is a second process drawing.

FIG. 4 is a third process drawing.

FIG. 5 is a view showing each of the steps in a flowchart.

FIG. 6 is a longitudinal sectional view of a conventional elastic support body containing a lead plug.

FIG. 7 is a first process diagram of manufacturing the lead plug-containing elastic bearing body of FIG. 6;

FIG. 8 is a second process drawing.

FIG. 9 is a diagram of a first hysteresis loop of a lead plug-containing elastic bearing body.

FIG. 10 is a diagram of a second history loop.

FIG. 11 is a plan view of a conventional lead plug-containing elastic bearing body at rest for illustrating a vibration experiment.

FIG. 12 is a longitudinal sectional view of FIG.

13 is a plan view of the lead plug-containing elastic bearing body of FIG. 11 when it is moved to the left.

FIG. 14 is a longitudinal sectional view of FIG.

FIG. 15 is a plan view of the lead plug-containing elastic bearing body of FIG. 11 when moved to the right.

FIG. 16 is a longitudinal sectional view of FIG.

17 (A) and 17 (B) are longitudinal cross-sectional views of part A of FIG. 13 under different vibration conditions, and FIG. 13 (C) is a sectional view of FIG.
It is a longitudinal cross-sectional view of the part B of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rubber layer 2 Reinforcement plate 3 Lead plug 4 Elastic bearing main body 5 Upper mounting member 6 Lower mounting member 7 Plug insertion hole 8 Fixing bolt 10 Cover plate 11 Base 12 Support base 13 Guide projection 14 Plug through hole 15 Adjustment plate 16 Perimeter split type REFERENCE SIGNS LIST 17 pressure plate 18 end of reinforcing plate 21 rubber layer 22 reinforcing plate 23 lead plug 24 elastic support body 25 upper mounting member 26 lower mounting member 27 plug fitting recess 28 plug through hole 29 gap

Claims (2)

[Claims] 1. A rubber layer and a reinforcing plate are laminated and integrated,
A structure in which a lead plug is provided to penetrate the elastic body and the reinforcing plate in the axial direction to form a resilient support body, and upper and lower mounting members are integrally mounted on the upper and lower sides of the resilient support body, respectively. In the elastic bearing member for use, the rubber layer is made of a linearly high-damping rubber material blended with a material (molecular design) so as to be more linear than the non-linearity of a normal high-damping rubber, and the damping performance thereby. An elastic bearing body for a structure, characterized in that one or two lead plugs, which compensate for the drop, are fitted into the center of the elastic bearing body. 2. A lead plug is erected on the upper surface of a lower mounting member placed on a support base, and each of the lead plugs has a plug insertion hole, and is more linear than normal nonlinearity of high damping rubber. A high-damping rubber material and a reinforcing plate, which are blended so as to be close to each other, are alternately laminated, fitted into the lead plug through a small gap, and the upper part of the lead plug protruding from the upper part of the laminate is attached to the upper part. A gap L is formed between the upper surface of the laminate and the lower surface of the upper mounting member in contact with the lower surface of the member, and the linearity is reduced while pressing the lead plug in the mold via the upper mounting member in the axial direction. A method for manufacturing an elastic bearing body for a structure, comprising heating and pressurizing a high-damping rubber material to vulcanize the material.