JP4783627B2 - Laminated rubber bearing - Google Patents

Description

  The present invention relates to a laminated rubber bearing for base-isolating and supporting a building or a structure, and more particularly to a laminated rubber bearing in which lead struts are loaded in a laminated body.

  Conventionally, in order to reduce the effect of buildings and structures such as buildings, etc. when an earthquake occurs, laminated rubber bearings with a laminate of rubber sheets and thin metal plates have been used. Yes. In addition, laminated rubber bearings to which a vibration damping function is added in addition to the original load support and vibration insulation functions by loading lead or the like in the laminated body have been put to practical use.

  As shown in FIG. 12A, a laminated rubber bearing body (hereinafter also referred to as LRB) 21 in which lead pillars are loaded on the central shaft portion of the laminated body is sandwiched between flanges 26 and 27 as shown in FIG. A cylindrical lead column 25 is disposed in the central axis portion of the laminated body 22 in a state of penetrating the laminated body 22, and when a vertical compressive load or a horizontal shear load acts due to an earthquake or the like, Along with the deformation, the lead strut undergoes plastic deformation, and this plastic deformation absorbs and attenuates the vibration energy of the supported object such as a building or structure. When a load history curve of such a laminated rubber bearing 21 is obtained, it is usually as shown in FIG.

  However, such a laminated rubber bearing is vulcanized with the plug pin inserted into the vertical through hole provided in the central shaft portion of the unvulcanized laminated body, and then the plug pin is pulled out. Since it is manufactured by inserting lead struts into the through holes, it takes time to prepare plug pins and to insert / remove plug pins, and therefore, a laminated rubber bearing body that can omit these steps has been proposed.

That is, lead braces instead of plug pins are inserted in advance in the through-holes of the unvulcanized laminate, set in the mold in this state, and heated and vulcanized while applying pressure from above and below. This eliminates the need for a plug pin and simplifies the manufacturing process without the need to pull out the plug pin after vulcanization (see, for example, Patent Document 1).
JP 2001-343040 A (pages 1 to 5 and FIGS. 1 to 8)

  However, like the above-mentioned laminated rubber bearing, when the lead strut is arranged in a state where the central axis portion of the laminated body is penetrated, when pressure is applied in the vertical direction when vulcanizing the laminated body, The lead strut becomes like a stick, and there is a risk of poor adhesion due to insufficient pressure applied to the rubber sheet and thin metal plate.

  Further, as a means for preventing such adhesion failure, the length of the lead strut is set to a length shorter than the length corresponding to the thickness of the unvulcanized laminate, and the upper mold of the mold and the plastic deformation member In some cases, a clearance is provided in advance to absorb the shrinkage allowance of the laminate due to the pressure of vulcanization so that sufficient pressure acts on the rubber sheet and thin metal plate. In some cases, the rubber of the rubber sheet penetrates into this portion and pressure is not sufficiently applied. In particular, poor adhesion occurs between the upper portion of the plastic deformation member and the rubber of the rubber sheet, and integral molding may not be possible.

  Furthermore, when the lead struts are arranged so as to penetrate the central shaft portion of the laminate, when the laminated rubber support is subjected to a compressive stress in the vertical direction and sheared in the lateral direction, A large stress acts on the overlapping part with the upper extension region of the lower surface, and on the side opposite to the deformation direction of the upper part of the laminate, there is a phenomenon that a part of the lead strut is pushed out and invades the interface between the rubber sheet and the thin metal plate. Arise. On the other hand, in the lower part of the laminated body, a phenomenon occurs in which a part of the lead strut is pushed out into the interface between the rubber sheet and the thin metal plate on the deformation direction side. Therefore, since the volume of the lead strut contributing to the damping is reduced, there is a problem that the damping performance of the laminated rubber bearing body is lowered.

  Therefore, the present invention not only simplifies the manufacturing process by eliminating the need for plug pins, but also improves the adhesion stability between the rubber sheet and the thin metal plate, or a part of the lead strut is thin with the rubber sheet during shear deformation. An object of the present invention is to provide a laminated rubber bearing body having improved surface pressure dependency by preventing extrusion between the metal plate and the metal plate, and having better damping performance.

In order to solve the above-mentioned problems, the laminated rubber bearing body according to claim 1 is a laminate in which flanges made of thick metal plates are disposed at upper and lower ends of a laminate in which rubber sheets and thin metal plates are alternately laminated. In the rubber bearing body, the lead struts are arranged along the vertical direction with a circumferential interval around the central axis in the laminate, and each lead strut is formed lower than the height of the laminate , One end of the lead strut is attached to the upper flange or the lower flange, the other end faces the laminate, and each lead strut is at an intermediate position in the vertical direction within the laminate with respect to the central axis of the laminate. It is characterized by being symmetrically arranged .

  According to the laminated rubber bearing body according to claim 1, the lead strut is formed lower than the height of the laminated body, and at least one end faces the laminated body. Even if it receives pressure in the vertical direction, the lead strut does not act like a replacement rod, and a predetermined pressure can be applied to the entire laminate. Therefore, poor adhesion hardly occurs between the rubber sheet, the thin metal plate, and the lead strut.

  Furthermore, since the lead strut is integrally formed in the laminated body without causing poor adhesion with the rubber sheet, a conventional laminated rubber bearing body having an insertion hole for the lead strut using a plug pin is used. Thus, the surface pressure dependency of the laminate is not reduced. Therefore, when the laminate is subjected to compressive force and undergoes shear deformation, the stress acting on the lead struts is relieved, so that a part of the lead struts is extruded between the rubber sheet and the thin metal plate. Phenomenon is less likely to occur.

  In addition, since at least one end of the lead strut faces the laminated body, a space is provided between the lead strut and the flange, so that the rubber elastic layer is hardened by deformation of the laminated body. Even if it is, buckling is unlikely to occur.

Moreover, about each lead support | pillar, it is desirable to make diameter 5-350mm, height 0.2-0.95 times of laminated body height, and make 2-30 pieces. Thereby, it can respond to a various laminated rubber bearing body from the thing of a low attenuation | damping to the thing of a high attenuation | damping. In addition, this laminated rubber bearing body exhibits the damping performance according to the total amount of lead. For example, increasing the number of lead columns increases the damping force.

Further, laminated rubber bearings of the present invention, in the vertical direction of the intermediate position of each lead strut the stack, it is also a feature which is symmetrically arranged relative to the central axis of the laminate. According to this configuration , the initial rigidity is reduced, and the horizontal elastic function and the restoring function of the laminate can be more effectively exhibited .

Further, in the laminated rubber bearing of the present invention , one end of each lead support is attached to the upper flange or the lower flange, and the other end faces the laminated body so as to be opposed to each other. According to this configuration, the lateral deformation of the laminate, it is possible to restrain in the lead post attached at one end to the upper flange or the lower flange, rigidity is up, is possible to improve the damping performance it can. In addition, this laminated rubber bearing body exhibits the damping performance according to the total amount of lead.

The laminated rubber bearing body according to claim 2 , wherein a plurality of sets of lead struts are arranged symmetrically with respect to the central axis of the laminate, and one lead strut of each set is arranged at an intermediate position in the vertical direction in the laminate. The other lead strut is composed of a pair of upper and lower lead struts, and is extended from the upper and lower flanges so that the inner ends of the laminate are disposed so as to face each other.

According to the laminated rubber bearing body of claim 2 , since it exhibits smooth shear deformation (lateral deformation of the laminated body), the surface pressure dependency is not easily lowered even when a large vertical load is applied. . That is, it is possible to suppress a decrease in horizontal rigidity with respect to a transverse shear deformation due to a vertical load.

The laminated rubber bearing body according to claim 3 is characterized in that an air vent hole communicating with at least one end side of each lead strut is provided in the upper flange, the lower flange, the upper flange or the lower flange, and the laminated body.

According to the laminated rubber bearing body according to claim 3 , when the laminated body is vulcanized by providing an air vent hole that communicates with each of the lead struts, the air between the lead strut and the rubber sheet is the laminated laminate. Since it can discharge | emit to the exterior of a body, an air pocket becomes difficult to produce between the said lead | read | reed support | pillar and the said rubber sheet, and adhesion failure can be prevented.

Since the laminated rubber bearing of the present invention has the above configuration, the following excellent effects can be obtained. That is,
Since the lead struts are built in the unvulcanized state of the rubber sheet of the laminate and vulcanized and integrally molded, the lead struts are inserted into the insertion holes formed using plug pins during vulcanization of the laminate as before. Compared with this, the manufacturing process is simplified and the manufacturing becomes easy.

  Moreover, since the height of the lead struts is lower than that of the laminate and loaded in the laminate, a predetermined pressure can be applied to the entire laminate when vulcanized, and the rubber sheet, the upper and lower flanges, and the thin metal The plate is securely bonded. Furthermore, since the plastic deformation characteristics (plastic hysteresis damping) of the lead strut can be utilized to the maximum, the damping performance is excellent.

If the lead struts are arranged in the laminated body as in the laminated rubber bearing body according to claim 2 , the laminated body is smoothly deformed when the laminated rubber bearing body undergoes shear deformation in the lateral direction due to vertical pressure. , Will exhibit better damping performance.

  Hereinafter, an embodiment of a laminated rubber support according to the present invention will be described with reference to the drawings.

  1 is a central longitudinal sectional view showing a first embodiment of a laminated rubber bearing, FIG. 2 is a sectional view taken along line BB of FIG. 1, FIG. 3 is a plan view of the laminated rubber bearing of FIG. FIG. 2 is a partially enlarged cross-sectional view showing a portion A of FIG. 1 in an enlarged manner.

  As shown in FIGS. 1 to 3, the laminated rubber bearing body (LRB) 1 of this embodiment is integrally provided with flanges 6 and 7 made of thick steel plates above and below the laminated body 2.

  In the laminate 2, a plurality of cylindrical lead plugs 5 are loaded as lead columns. In this example, the height (length) of each lead plug 5 is as short as about 1/2 (50 mm) of the height of the laminated body 2, and the diameter is also the conventional LRB (diameter 300 mm with a diameter of 60 mm in the center). The diameter is reduced to about 1/2 of that of a 125 mm long lead plug (lead strut). However, in this example, the total volume of the nine lead plugs 5 is generally matched to the volume of one conventional LRB lead plug.

  These lead plugs 5 are arranged symmetrically with respect to the central axis s of the laminated body 2, and one of the sets is composed of one lead plug 5 arranged at an intermediate position in the vertical direction in the laminated body 2. The other is made up of a pair of upper and lower lead plugs 5, 5 disposed in the laminated body 2 so as to be opposed to each other. The pair of upper and lower lead plugs 5 are arranged so that one end is fitted in the recesses 6a and 7a provided on the upper and lower flanges 6 and 7 and the other end faces the laminated body 2 so as to face each other. ing.

  The laminate 2 has a structure in which the rubber sheets 3 and the thin steel plates 4 are alternately laminated. The insertion holes 2a, 2b, and 2c are provided in advance at the positions of the rubber sheets 3 and the thin steel plates 4 into which the lead plugs 5 are loaded. Is drilled.

  Also, an air vent hole 8 communicating with the upper end of the insertion hole 2a is formed in the upper flange 6 and the rubber sheet 3 and the thin steel plate 4 above the laminate 2, and an air vent hole 9 communicating with the concave portion 6a of the upper flange 6 is formed in the upper flange 6. Air vent holes 10 communicating with the recesses 7a of the lower flange 7 are formed in the lower flange 7, respectively. In the case of this example, the air vent hole 8 has a diameter of 9 mm, which is larger than the diameter of the other air vent holes 9 and 10 of 3 mm. This is because the air between the lead plug 5 and the rubber of the rubber sheet 3 is discharged so that no air pool is generated. Thereby, the adhesion failure by an air pocket can be prevented.

  As shown in FIG. 1, the periphery of the laminate 2 and the upper and lower flanges 6, 7 are covered with a rubber sheet 11, but as shown in FIG. 4, the lower peripheral edge of the upper flange 6 and the upper and lower sides of each thin steel plate 4 Each of the peripheral portions is formed in a round shape, and in particular, the lower end peripheral portion of the flange 6 is formed in an arc having a cross section of a radius of 3 mm. Although illustration is omitted, the peripheral edge of the upper end of the lower flange 7 is also formed in an arc having a cross section of a radius of 3 mm. This is to avoid stress concentration and prevent the rubber layer such as the coated rubber sheet 11 from cracking.

  When a vertical pressure acts on the laminated rubber support 1 and the laminated body 2 is sheared and deformed in the horizontal direction, the thin steel plate 4 bites into the side surface of the lead plug 5 as shown in FIG. Plastic deformation occurs in the plug 5. Thus, the lead plug 5 is plastically deformed to absorb the energy in the horizontal direction and attenuate the vibration of the supported object.

  In addition, although the seismic isolation bearing body using the elasticity of steel materials as shown in FIG.11 (b) has already been proposed, the mechanism of damping is completely different from the laminated rubber bearing body of the present invention.

  In other words, the seismic isolation bearing body 100 is formed by sandwiching a laminated body 120 of rubber and a thin steel plate between an upper flange 115 and a lower flange 116, and two cylindrical steel materials at the central shaft portion of the laminated body 120. 124 and 125 are loaded. These steel materials 124 and 125 are arranged vertically with one end thereof being relatively bent, and the other end portions are fixed to the upper flange 111 and the lower flange 112, respectively. An attenuation agent layer 129 such as acrylic rubber is provided on the central shaft portion of the laminate 120 so as to cover the outer surfaces of the steel materials 124 and 125. In the seismic isolation bearing 100, connecting flanges 111 and 112 are attached to an upper flange 115 and a lower flange 116, respectively.

  In the case of such a seismic isolation bearing body 100, as shown in FIG. 11 (c), when the laminated body 120 is shear-deformed in the horizontal direction, each thin steel plate 131 moves horizontally and pushes the steel material side surface at its end. Thus, the steel material 125 is elastically deformed. Thus, energy is absorbed by the steel materials 124 and 125 being elastically deformed.

  Therefore, in the case of the seismic isolation bearing body 100, it is meaningless if the thin steel plate 131 bites into the steel materials 124 and 125, while the laminated rubber bearing body of the present invention is intended if the thin steel plate does not bite into the lead plug. A damping effect cannot be obtained.

  Next, a manufacturing method for the laminated rubber bearing body 1 according to this embodiment having the above-described configuration will be described. The unvulcanized rubber sheet 3 and the thin steel plate 4 are alternately laminated to form a laminated body 2, and the lead plug 5 is inserted into the insertion holes 2a to 2c of the laminated body 2, but is inserted into the insertion holes 2b and 2c. One end of the lead plug 5 is fitted into the recesses 6a and 7a of the upper and lower flanges 6 or 7, and the lead plug 5 is inserted with the flanges 6 and 7 attached to the upper and lower sides of the laminate 2.

  In this state, the unvulcanized rubber sheet 11 is wound around the outer periphery of the laminate 2 and the upper and lower flanges 6 and 7 and inserted into a mold (not shown). Then, a pressurizing force is applied from above and below, heated and vulcanized. At this time, excess air escapes from the air vent holes 8 to 10.

  In this way, the lead plug 5 is assembled before the rubber sheets 3 and 11 are vulcanized and formed integrally with the laminate 2, so that the conventional manufacturing method, that is, the insertion formed using the plug pins after vulcanization of the laminate 2 is performed. Compared with fitting in the hole, the manufacturing process is simplified, the time required for manufacturing is shortened, and the work is facilitated.

  Since the manufactured laminated rubber bearing 1 disperses the lead plug 5 in the circumferential direction and the vertical direction around the central axis s of the laminated body 2, a conventional large diameter lead plug is loaded on the central axis of the laminated body. Compared to the laminated rubber support, it is possible to eliminate a large cross-sectional defect in the loaded portion, and it is possible to smoothly deform the laminated body 2 in the horizontal direction. Therefore, an improvement in the surface pressure dependency can be expected when the lead plug is subjected to a compressive force in the vertical direction and is deformed in a shear (horizontal direction).

  In addition, since the concentration of stress on one lead plug can be prevented by dispersing the lead plug, the phenomenon that a part of the lead plug protrudes from the boundary surface between the rubber sheet and the thin metal plate in the laminate during large deformation due to seismic energy, etc. it can.

  FIG. 5 is a diagram in which the load history curve of the laminated rubber bearing body 1 of the above embodiment and the load history curve of the conventional LRB are overlapped. As shown in FIG. 5, the laminated rubber bearing body of the above embodiment is shown. It can be seen that 1 is better.

  FIG. 6 is a central sectional view showing a second embodiment of the laminated rubber bearing body of the present invention. As shown in the figure, the laminated rubber bearing body 1 ′ of the second embodiment has the height of the lead plug 5 laminated. The height is 0.95 times the height of the body 2, the diameter is 20 mm, the number used is six, and the total volume of the lead plug 5 is made substantially equal to the volume of the lead plug of the conventional LRB.

  And the recessed part 6a is provided in the lower surface of the upper flange 6 around the central axis s at equal intervals, the lead plug 5 is fitted to each recessed part 6a and extends downward, and the insertion is provided downward from the upper surface of the laminate 2 It is inserted into the hole 2d. In this state, the unvulcanized rubber sheet 11 is wound, applied pressure is applied from above and below, heated and vulcanized, and the lead plug 5 is integrally loaded in the laminate 2.

  Although not shown, the upper flange 6 and the lower flange 7 are provided with recesses 6a and 7a alternately so as to be symmetrical with respect to the central axis s of the laminate 2, and lead plugs 5 are provided in the recesses 6a and 7a. The lead plug 5 extending downward from the upper flange 6 and the lead plug 5 extending upward from the lower flange 7 are inserted upward and downward from the bottom surface of the laminate 2. It is also possible to vulcanize by inserting into an insertion hole provided in the plate and pressurizing and heating from above and below.

  In addition, as shown in FIG. 7, in the process of forming a lead plug 5 that is low (short) about 1/3 of the height of the multilayer body 2 and assembling the multilayer body 2, They are inserted into the respective insertion holes 2a provided at equal intervals in the circumferential direction around the central axis s so as to be vertically symmetric with respect to the same central axis at the intermediate position. Then, the flanges 6 and 7 are attached to the upper and lower sides of the laminate 2, and the unvulcanized rubber sheet 11 is wrapped around the periphery and covered, and then set in a mold and vulcanized by pressing from above and below. A laminated rubber bearing body 1 ″ in which the plug 5 is integrated with the laminated body 2 can be formed.

  When the laminated rubber bearing body 1 ″ of the third embodiment is sheared and deformed by applying pressure from above and below, the laminated body 2 is provided with the lead plug 5 and the rigid middle portion changes the direction of the lead plug 5. Deformation that slides in the horizontal direction while maintaining the vertical direction occurs.

  When the load history curve at this time is obtained, the result is as shown in FIG. 8, and the spring characteristics such as the horizontal elastic function and the restoring function of the laminate 2 are more effectively exhibited. Recognize. Note that by changing the diameter, length, and number of the lead plugs 5, the total amount of lead that contributes to attenuation can be changed, and the damping force can be adjusted.

  Furthermore, as shown in FIG. 9, the lead plug 5 can also be arrange | positioned. The laminated rubber bearing body 1 '' 'according to the fourth embodiment has a pair of upper and lower lead plugs 5, 5 arranged around the central axis s of the laminated body 2 at regular intervals in the circumferential direction. Each of the pair of lead plugs 5 is disposed in a state in which one end is fitted into the recesses 6 a and 7 a of the upper and lower flanges 6 and 7 and the other end is relatively bent in the laminated body 2. The flanges 6 and 7 are respectively provided with air vent holes 9 and 10 that allow the recesses 6a and 7a to communicate with the outside.

  When this laminated rubber bearing body 1 '' 'is subjected to shear deformation by applying pressure from above and below, the laminated body 2 has an upper end portion and a lower end portion that are provided with lead plugs 5 and have high rigidity. A deformation that slides in the horizontal direction while maintaining the orientation of the lead plug 5 in the vertical direction occurs, and a load history curve that exhibits better damping performance than the laminated rubber bearing body 1 ″ of the third embodiment as shown in FIG. It should be noted that by changing the diameter, length, and number of the lead plug 5, the total amount of lead that contributes to attenuation can be changed, and the damping force can be adjusted.

It is a center longitudinal cross-sectional view which shows 1st Example of the laminated rubber bearing body concerning this invention. It is the BB sectional view taken on the line in FIG. It is a top view of the laminated rubber support body of FIG. It is a partial expanded sectional view which expands and shows the A section of FIG. It is the graph which overlap | superposed the load history curve of the laminated rubber bearing body 1 of 1st Example, and the load history curve of the conventional LRB. It is a center sectional view showing the 2nd example of the lamination rubber bearing object concerning the present invention. It is a center sectional view showing the 3rd example of the lamination rubber bearing object concerning the present invention. It is a load history curve of the laminated rubber bearing body of 3rd Example. It is a center sectional view showing the 4th example of the lamination rubber bearing object concerning the present invention. It is a load history curve of the laminated rubber bearing body of 4th Example. (A) It is explanatory drawing which shows the mechanism of attenuation | damping of the laminated rubber bearing body concerning this invention. (B) is the center longitudinal cross-sectional view of the seismic isolation bearing using the elasticity of steel materials, (b) is explanatory drawing which shows the mechanism of the attenuation | damping. (A) shows the perspective view of the conventional laminated rubber bearing body with a lead support | pillar, and in order to show the internal structure, a part is represented by the cross section. (B) is a graph which shows the hysteresis curve of the conventional laminated rubber bearing body with a lead support | pillar.

Explanation of symbols

1, 1 ', 1 ", 1'" Laminated rubber support body 2 Laminated body 2a, 2b, 2c Insertion hole 3 Rubber sheet 4 Thin metal plate 5 Lead plug 6/7 Flange 6a / 7a Recessed 8, 9, 10 Air vent Hole 11 Rubber sheet

Claims (3)

In a laminated rubber bearing body in which flanges made of thick metal plates are arranged on both upper and lower ends of a laminate in which rubber sheets and thin metal plates are alternately laminated,
While arranging the lead struts around the central axis in the laminate along the vertical direction at intervals in the circumferential direction, each lead strut is formed lower than the height of the laminate ,
One end of each of the lead struts is attached to the upper flange or the lower flange, the other end faces the laminate, and each lead strut is positioned at the center axis of the laminate at an intermediate position in the vertical direction in the laminate. Laminated rubber bearings symmetrically arranged . While arranging a plurality of sets of the lead struts symmetrically to the central axis of the laminate,
One lead strut of each set is arranged at an intermediate position in the vertical direction in the laminate, and the other lead strut is composed of a pair of upper and lower lead struts and is extended from the upper and lower flanges to be inside the laminate The laminated rubber bearing body according to claim 1, wherein the ends are arranged so as to be relatively inclined.   The laminated rubber bearing body according to claim 1 or 2, wherein an air vent hole communicating with at least one end side of each of the lead struts is provided in the upper flange, the lower flange, the upper flange, the lower flange, and the laminated body.

Images