JP5960492B2 - Laminated rubber - Google Patents

Description

  The present invention relates to a laminated rubber.

  A laminated rubber in which a plurality of layers made of a rubber plate and a rigid plate are laminated is used for a support portion of a structure such as a building. In addition, there is one in which a plug having a damping performance formed of a mixture of iron powder and an elastomer composition (viscous material) is loaded at the center of such a laminated rubber (for example, Patent Document 1).

  By the way, in the manufacturing process, since the plug is molded by pressing from both ends toward the center, the concentration of iron powder constituting the plug is different between the both ends and the center of the plug, and both ends of the plug are The shear rigidity may be lower than that at the center of the plug. Here, at the time of shear deformation of the laminated rubber, since the shear rigidity of the plug affects the shear strain amount of the surrounding rubber plate, in the above case, the inclination angle of the rubber plate at both ends in the lamination direction of the laminated rubber Is larger than the inclination angle of the rubber plate in the central portion in the lamination direction, and the inclination angle of each rubber plate of the laminated rubber is not uniform in the lamination direction. If the inclination angle of each rubber plate of the laminated rubber becomes non-uniform in the laminating direction, the limit characteristics of the laminated rubber, particularly the limit characteristics of breakage, are deteriorated.

JP 2009-133481 A

  An object of the present invention is to provide a laminated rubber in which the inclination angle of each rubber plate in the laminated rubber is uniform in the lamination direction when the laminated rubber is subjected to shear deformation.

The laminated rubber according to claim 1, wherein the laminated rubber is formed by mixing iron powder and a viscous material, and a rubber plate formed with a through hole into which a plug having a lower shear rigidity is loaded at both ends than at the center. A plurality of layers composed of rigid plates are laminated, and the ratio (tr / ts) between the thickness tr of the rubber plate and the thickness ts of the rigid plate constituting the layers at both ends in the laminating direction is set to the central portion in the laminating direction. of the layer in size than Kusuru the ratio between the thickness ts of the rigid plate and the thickness tr of the rubber plate forming (tr / ts) and the shear deformation of the horizontal direction of the rubber plate in the stacking direction at both ends The amount of shear deformation in the horizontal direction of the rubber plate at the center in the stacking direction is set to be smaller .

In the laminated rubber according to claim 1, a plurality of layers including a rubber plate and a rigid plate in which a through-hole into which a plug having a damping performance is loaded are stacked, and the rubber plate constituting the layer is formed. The ratio (tr / ts) between the thickness tr and the thickness ts of the rigid plate is larger at both ends in the stacking direction than at the center in the stacking direction. The larger the thickness ratio (tr / ts), the larger the proportion of the rubber plate in one layer, and the smaller the shear deformation amount of the rubber plate.
In addition, since the plug is composed of a mixture of iron powder and rubber, the burden on the environment can be reduced as compared with the case where a lead plug or the like is used.

  The laminated rubber according to claim 2 is the laminated rubber according to claim 1, wherein the ratio (tr / ts) of the thickness tr of the rubber plate and the thickness ts of the rigid plate constituting the layer is determined as described above. It is characterized in that it is varied in the laminating direction according to the shear rigidity of the rubber plate and the shear rigidity in the height direction of the plug.

  In the laminated rubber according to claim 2, the ratio (tr / ts) of the thickness tr of the rubber plate and the thickness ts of the rigid plate constituting the layer is determined in accordance with the shear rigidity of the rubber plate and the height direction of the plug. It is changed in the stacking direction according to the shear rigidity. Thereby, even if the rubber plates of the respective layers constituting the laminated rubber have different shear rigidity, the thicknesses of the rubber plate and the rigid plate are determined according to the shear rigidity of each rubber plate and the shear rigidity in the height direction of the plug. By changing the ratio (tr / ts), the inclination angle of each rubber plate of the laminated rubber can be made uniform in the laminating direction at the time of shear deformation of the laminated rubber.

The laminated rubber according to claim 3 is the laminated rubber according to claim 1 or 2 , wherein the thickness ts of the rigid plate constituting the layers at both ends in the laminating direction is set to the layer at the center in the laminating direction. The rigid plate is formed thinner than the thickness ts.

  Since this invention set it as said structure, the laminated rubber from which the inclination | tilt angle of each rubber plate in laminated rubber becomes uniform in a lamination direction can be provided.

It is a partially broken perspective view of the laminated rubber according to the first embodiment. It is sectional drawing which shows the state which integrated and vulcanized | stacked the laminated rubber which concerns on 1st Embodiment. It is sectional drawing which shows the laminated rubber which concerns on 1st Embodiment attached to the structure. It is sectional drawing which shows the state which the laminated rubber which concerns on 1st Embodiment attached to the structure is carrying out the shear deformation. It is sectional drawing of the laminated rubber which concerns on 2nd Embodiment attached to the structure. It is sectional drawing which shows the state which the laminated rubber which concerns on 2nd Embodiment attached to the structure is carrying out the shear deformation.

  Hereinafter, the laminated rubber according to the first embodiment will be described with reference to the drawings. As shown in FIG. 1, the laminated rubber 10 according to the present embodiment has a cylindrical shape, and a plurality of layers 16 composed of a rubber plate 12 and a rigid plate 14 are laminated and vulcanized and bonded together. Although the number of the layers 16 constituting the laminated rubber 10 varies depending on the seismic isolation conditions given to the structure supported by the laminated rubber 10, in the present embodiment, eight layers are taken as an example. The outer peripheral surface of the laminated rubber 10 is covered with a covering rubber 18 to suppress the deterioration of the laminated rubber 10.

  A through hole 20 that penetrates the rubber plate 12 and the rigid plate 14 in the laminating direction is formed at the center of the laminated rubber 10. The through hole 20 is loaded with a plug 22 having damping performance. The plug 22 is formed of a mixture of iron powder and an elastomer composition, and the outer diameter of the plug 22 is about one fifth of the outer diameter of the laminated rubber 10.

  A disk-like lower flange 24 is vulcanized and bonded to the lower surface of the laminated rubber 10 at the lower end in the laminating direction of the laminated rubber 10. The lower flange 24 is formed to have a larger diameter than the laminated rubber 10, and a plurality of bolt holes 26 penetrating the lower flange 24 are formed on the outer periphery of the lower flange 24. Bolts 28 are inserted into the bolt holes 26 and fixed to the lower structure 30 positioned below the laminated rubber 10 (see FIG. 3).

  A disc-shaped upper flange 32 is vulcanized and bonded to the upper surface of the laminated rubber 10 at the upper end of the laminated rubber 10 in the lamination direction. A plurality of bolt holes 26 are formed in the outer peripheral portion of the upper flange 32, and bolts 28 are inserted into the bolt holes 26 and fixed to the upper structure 34 positioned above the laminated rubber 10 (FIG. 3). reference). Thus, the plurality of laminated rubbers 10 are disposed between the lower structure 30 and the upper structure 34 to support the upper structure 34.

  Next, an example of the vulcanization process of the laminated rubber 10 according to the present embodiment will be described. As shown in FIG. 2, first, the through hole 20 formed at the center of the upper flange 32 is inserted into a columnar metal column 36 erected from the pedestal 38. Next, the through hole 20 formed in the center of the rubber plate 12 and the rigid plate 14 is inserted into the metal support 36, and the rubber plate 12 and the rigid plate 14 are alternately stacked on the metal support 36.

  After a predetermined number of unvulcanized rubber plates 12 and rigid plates 14 are inserted into the metal columns 36, the lower flange 24 is placed on the rubber plate 12. When the rubber plate 12, the rigid plate 14, and the upper flange 32 are positioned, the outer peripheral surfaces of the rubber plate 12 and the rigid plate 14 are covered with the covering rubber 18.

  Next, the rubber plate 12, the rigid plate 14, the upper flange 32, and the lower flange 24 are surrounded by the mold 40. Thereafter, the pressure block 42 is pressed from above the mold 40, and pressure is applied to the lower flange 24 in the vertical direction for a certain time by a press machine (not shown) connected to the pressure block 42. At the same time, the heater 44 provided inside the base 38 and the pressure block 42 is operated to heat the upper flange 32, the lower flange 24, and the mold 40. By this pressure and heat, the rubber plate 12 and the rigid plate 14 are vulcanized and bonded, and the lower flange 24 and the rubber plate 12, and the upper flange 32 and the rubber plate 12 are also vulcanized and bonded.

  When the vulcanization adhesion is completed, the pressure block 42 is pulled upward, the mold 40 is disassembled, and the laminated rubber 10 integrated by the vulcanization adhesion is taken out from the mold 40. Thereafter, the metal support 36 is removed from the laminated rubber 10, and the plug 22 molded in another process is press-fitted into the through hole 20 of the laminated rubber 10.

  Next, a detailed configuration of the laminated rubber 10 will be described. As shown in FIG. 3, the concentration of iron powder in the plug 22 loaded on the laminated rubber 10 is higher in the center than at both ends of the plug 22. This is due to the molding process of the plug 22, and when the plug 22 is compression molded, the iron powder moves through the plug 22, whereby the concentration of the iron powder in the plug 22 varies. Here, the shear rigidity of the plug 22 greatly depends on the concentration of the iron powder in the plug 22, and both ends of the plug 22 have a lower shear rigidity than the central portion, so the shear rigidity is low. . In addition, the distribution of the iron powder in the drawing is drawn with exaggerated variation in concentration for convenience of explanation.

  When the eight layers 16 constituting the laminated rubber 10 are sequentially designated as a layer 16A, a layer 16B,..., A layer 16H from the lower end in the laminating direction, the layer 16D and the layer 16E located at the center in the laminating direction are rubber plates. 12 and the rigid plate 14 are set to have the same thickness. In the present embodiment, as an example, trD, trE, tsD, and tsE are all set to 6 mm, and the layer thicknesses of the layer 16D and the layer 16E are each 12 mm. For this reason, the ratio (tr / ts) of the thicknesses of the rubber plate 12 and the rigid plate 14 of the layers 16D and 16E is 1.

  On the other hand, the layer 16A, the layer 16B, and the layer 16C at the lower end in the stacking direction of the laminated rubber 10 are set to have a layer thickness of 12 mm. The ratio of the thickness of the rubber plate 12 and the rigid plate 14 is determined by the shear of the rubber plate 12. Depending on the rigidity and the shear rigidity of the plug 22, it changes in the stacking direction. That is, the rubber plate 12 constituting the lowermost layer 16A has higher shear rigidity than the rubber plate 12 constituting the other layer 16, and the shear rigidity of the plug 22 located in the lowermost layer 16A is lower than the central portion. The thickness ratio (trA / tsA) between the rubber plate 12 and the rigid plate 14 is set to be large. In the present embodiment, the thickness trA of the rubber plate 12 is 9 mm, and the thickness tsA of the rigid plate 14 is 3 mm. For this reason, the ratio of the thickness of the rubber plate 12 and the rigid plate 14 (trA / tsA) is 3/1.

Hereinafter, a method for setting the thickness trA of the rubber plate 12 and the thickness tsA of the rigid plate 14 of the lowermost layer 16A will be described. In the present embodiment, the respective thicknesses are designed so that the shear strain γ _A of the rubber plate 12 of the lowermost layer 16A is equal to the shear strain γ _D of the rubber plate 12 of the layer 16D located in the center in the stacking direction. .

First, when a predetermined shearing force is applied to the laminated rubber 10, the same shearing force is generated in the layer 16 </ b> A and the layer 16 </ b> D, and therefore the following equation (1) is established. In Equation (1), the shear stiffness of the plug 22 located in the lowermost layer 16A is G _p1 , the shear stiffness of the plug 22 located in the layer 16D is G _p2 , and the shear stiffness of the rubber plate 12 is G _r . Also, the horizontal cross-sectional area of the plug 22 to _{A p,} the horizontal cross-sectional area of the rubber plate 12 and _{A r.}
・ ・ ・ ・ ・ ・ ・ (1)

Here, as described above, in the present embodiment, since the thickness of the rubber plate 12 and the rigid plate 14 of the layer 16D are equal, trD = tsD. Further, since the shear strain γ _A and the shear strain γ _D are designed to be equal, γ _A = γ _D. Substituting these into equation (1) and calculating leads to the following equation (2).
・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ (2)

Since the shear rigidity G _p1 and G _p2 of the plug 22 according to the present embodiment are G _p1 = 2 and G _p2 = 3, respectively, (trA / tsA) is 3 / 1. Based on the thickness ratio thus calculated, the thickness trA of the rubber plate 12 of the layer 16A and the thickness tsA of the rigid plate 14 are set.

Next, the thickness ratio (trB / tsB) between the rubber plate 12 and the rigid plate 14 constituting the second layer 16B from the lowermost layer 16A is set to be slightly larger than that of the lowermost layer 16A. This is because the shear rigidity of the plug 22 located in the layer 16B is slightly higher than the shear rigidity of the plug 22 located in the lowermost layer 16A. In the present embodiment, when the shear rigidity G _pB of the plug 22 positioned in the layer 16B is 2.4, the rubber plate 12 has a thickness trB of 7.5 mm, the rigid plate 14 has a thickness tsB of 4.5 mm, and the rubber The thickness ratio (trB / tsB) between the plate 12 and the rigid plate 14 is set to 5/3.

  Further, since the lowermost layer 16 to the third layer 16C have a slightly higher shear rigidity than the second layer 16B, when the shear rigidity of the plug 22 here is 2.7, the thickness trC of the rubber plate is set. The thickness tsC of the rigid plate 14 is 5.33 mm, and the thickness ratio (trC / tsC) is set to 5/4.

  Furthermore, the layers 16H, 16G, and 16F at the upper end in the stacking direction of the laminated rubber 10 have the same configuration as the layers 16A, 16B, and 16C at the lower end in the stacking direction, and the rubber plates that constitute the layers 16H, 16G, and 16F The thicknesses trH, trG, trF of 12 are set to 9 mm, 7.5 mm, and 6.67 mm.

  As described above, the thickness ratio (tr / ts) between the rubber plate 12 and the rigid plate 14 is set so as to gradually decrease from both end portions in the stacking direction of the laminated rubber 10 toward the center portion in the stacking direction. A rubber plate 12 for vulcanization adhesion is laminated between the layer 16H and the upper flange 32.

In the present embodiment, the lower flange 24 and the upper flange 32 are vulcanized and bonded to the laminated rubber 10, but may be bonded to the laminated rubber 10 by other bonding methods. For example, you may adhere | attach with an adhesive agent etc. In this case, even if there is no rubber plate 12 between the layer 16H and the upper flange 32, it can be bonded.
Moreover, although the plug 22 according to the present embodiment is formed by mixing iron powder and an elastomer composition, other metal may be used instead of the iron powder, and other viscosity may be used instead of the elastomer composition. A material may be used.

  Furthermore, in the present embodiment, the ratio of the thicknesses of the rubber plate 12 and the rigid plate 14 that are three layers from the bottom layer (layer 16A, layer 16B, layer 16C) and three layers from the top layer (layer 16H, layer 16G, layer 16F). However, the present invention is not limited to this. For example, only the ratio of the rubber plate 12 and the rigid plate 14 of the lowermost layer 16A and the uppermost layer 16H may be changed. Further, the thickness ratio may be changed in all layers 16 constituting the laminated rubber 10.

  Next, the operation of the laminated rubber 10 according to this embodiment will be described. As shown in FIG. 4, when an earthquake occurs, the lower structure 30 is moved relative to the upper structure 32 in the direction of arrow A by the seismic force, and the laminated rubber 10 is shear-deformed in the horizontal direction. In this way, the laminated rubber 10 undergoes shear deformation, thereby suppressing vibration from being transmitted to the upper structure 32.

  Here, since the shear rigidity of both ends of the plug 22 loaded in the laminated rubber 10 is lower than the shear rigidity of the central part of the plug 22, if the thickness of the rubber plate 12 is the same in the lamination direction, the shear The shear deformation amount at both ends in the laminating direction with low rigidity increases.

  On the other hand, the thickness ratio (tr / ts) of the rubber plate 12 and the rigid plate 14 constituting the layers 16A, 16B, and 16C at the lower end in the stacking direction of the laminated rubber 10 is the shear rigidity of the rubber plate 12 in each layer 16. According to the shear rigidity in the height direction of the plug 22, the thickness ratio (tr / ts) of the rubber plate 12 and the rigid plate 14 constituting the layers 16D and 16E in the central portion in the stacking direction is larger. As a result, in the layers 16A, 16B, and 16C at the lower end in the stacking direction, the shear deformation amount decreases as the ratio of the thickness of the rubber plate 12 to the thickness of each layer increases. For this reason, the increase in the amount of shear deformation due to the decrease in shear rigidity is offset.

  Similarly, the layers 16F, 16G, and 16H at the upper end in the laminating direction of the laminated rubber 10 have a smaller shear deformation amount because the ratio of the thickness of the rubber plate 12 to the layer thickness of each layer is larger. For this reason, the increase in the amount of shear deformation due to the decrease in shear rigidity is offset, and the amount of shear deformation becomes equal. That is, the inclination angle θ of each rubber plate 12 of the laminated rubber 10 is uniform in the laminating direction. Here, the inclination angle θ is an angle determined by tan θ = (shear deformation amount of rubber plate 12 / ts).

  In the present embodiment, the ratio (trA / tsA) of the thickness trA of the rubber plate 12 of the lowermost layer 16A and the thickness tsA of the rigid plate 14 is 3/1, but the rubber plate 12 occupies the layer thickness of each layer. The ratio of the thickness is appropriately set according to the shear rigidity of the plug 22 and the shear rigidity of the rubber plate 12.

  In this embodiment, the thickness of all the layers 16 constituting the laminated rubber 10 is unified at 12 mm. However, if the ratio of the thicknesses of the rubber plate 12 and the rigid plate 14 changes in the laminating direction, each layer It is not necessary to unify the layer thickness.

  Furthermore, in the present embodiment, the thickness of the rubber plate 12 is increased from the central portion in the stacking direction toward both ends in the stacking direction so that the thickness ratio (tr / ts) is greater than 1. The thickness of the rubber plate 12 may be reduced toward the central portion in the stacking direction so that the thickness ratio (tr / ts) becomes smaller than 1.

  Next, the laminated rubber 50 according to the second embodiment of the present invention will be described. In addition, the same code | symbol is attached | subjected about the structure same as 1st Embodiment, and description is abbreviate | omitted. As shown in FIG. 5, the laminated rubber 50 according to the present embodiment is configured by laminating eight layers 16 composed of a rubber plate 12 and a rigid plate 14 as in the first embodiment. An upper flange 32 and a lower flange 24 are vulcanized and bonded to the rubber plate 12 on the upper and lower surfaces of the laminated rubber 50. Further, the laminated rubber 50 is loaded with a plug 22 formed by mixing iron and an elastomer composition.

  In the three layers (layer 16A, layer 16B, layer 16C) at the lower end in the stacking direction of the laminated rubber 50 and the three layers (layer 16F, layer 16G, layer 16H) at the upper end in the stacking direction, the thickness of the rubber plate 12 is rigid. The thickness is twice that of the plate 14. In the present embodiment, as an example, the thickness of the rubber plate 12 is 6 mm, and the thickness of the rigid plate 14 is 3 mm. That is, the thickness ratio (tr / ts) is set to 2/1.

  The layers 16D and 16E in the center in the stacking direction of the laminated rubber 50 have the same thicknesses of the rubber plate 12 and the rigid plate 14. In this embodiment, as an example, both are set to 3 mm. That is, the thickness ratio (tr / ts) is set to 1.

  As shown in FIG. 6, when an earthquake occurs, the lower structure 30 moves relative to the upper structure 32 in the direction of arrow B by the seismic force, and the laminated rubber 50 is shear-deformed in the horizontal direction. In this way, the laminated rubber 50 undergoes shear deformation, and thus vibrations are prevented from being transmitted to the upper structure 32.

  Further, the shear stiffness at both ends of the plug 22 loaded in the laminated rubber 50 is lower than the shear stiffness at the center of the plug 22, and the shear stiffness of the rubber plates 12 at both ends in the lamination direction of the laminated rubber 50 is laminated. Since it is lower than the shear rigidity of the rubber plate 12 at the center in the direction, if the thickness of the rubber plate 12 is the same in the stacking direction, the amount of shear deformation at both ends of the plug 22 in the stacking direction becomes large.

  On the other hand, the thickness ratio (tr / ts) of the rubber plate 12 and the rigid plate 14 in the layers 16 (layer 16A, layer 16B, layer 16C, layer 16F, layer 16G, layer 16H) at both ends in the lamination direction of the laminated rubber 50. Is larger than the ratio (tr / ts) of the thickness of the rubber plate 12 and the rigid plate 14 in the layer 16 (layer 16D, layer 16E) in the center in the stacking direction. Thereby, the difference in shear deformation due to the difference in shear rigidity in the lamination direction of the laminated rubber 50 and the difference in shear rigidity in the height direction of the plug 22 is offset, and the rubber plates 12 of the laminated rubber 50 at the time of shear deformation are offset. The inclination angle θ can be made uniform in the stacking direction.

  In addition, the laminated rubber 50 according to the present embodiment is composed of only three kinds of the rigid plate 14 having a thickness of 3 mm, the rubber plate 12 having a thickness of 6 mm, and the rubber plate 12 having a thickness of 3 mm. Can be reduced. Further, when the number of layers 16 to be laminated is large, the present embodiment in which the rubber plate 12 has only two thicknesses can reduce the time required for assembly as compared with the laminated rubber 50 of the first embodiment.

  In this embodiment, the thicknesses of the rubber plates 12 of the three layers (layer 16A, layer 16B, layer 16C) at the lower end in the stacking direction and the three layers (layer 16F, layer 16G, layer 16H) at the upper end in the stacking direction are set. Although changed, the region where the thickness of the rubber plate 12 is changed is appropriately set according to the shear rigidity of the laminated rubber 50 and the shear rigidity of the plug 22. For example, the laminated rubber 50 may be configured by changing the thickness of the rubber plate 12 only in the lowermost layer 16A and the uppermost layer 16H.

  The first embodiment and the second embodiment of the present invention have been described above. However, the present invention is not limited to such an embodiment, and can be implemented in various modes without departing from the gist of the present invention. Of course. For example, the outer dimensions of the plug 22 may be further increased according to the required attenuation performance.

10 Laminated rubber 12 Rubber plate 14 Rigid plate 16 Layer 16A Layer 16B Layer 16C Layer 16D Layer 16E Layer 16F Layer 16G Layer 16H Layer 20 Through-hole 22 Plug 24 Lower flange (flange)
32 Upper flange (flange)
50 Laminated rubber 60 Laminated rubber

Claims (3)

A plurality of layers consisting of a rubber plate and a rigid plate, which are formed by mixing iron powder and a viscous material and are formed with through-holes that are loaded with plugs whose shear rigidity is lower at both ends than at the center, are laminated. And the ratio (tr / ts) of the thickness tr of the rubber plate constituting the layer at both ends in the laminating direction and the thickness ts of the rigid plate is determined by the ratio of the rubber plate constituting the layer at the central portion in the laminating direction. than the size Kusuru that the ratio between the thickness ts of the the thickness tr rigid plates (tr / ts), the horizontal of the rubber plate in the stacking direction central portion of the horizontal shear deformation of the rubber plate in the stacking direction at both ends Laminated rubber that is smaller than the amount of shear deformation in the direction .   The ratio (tr / ts) between the thickness tr of the rubber plate constituting the layer and the thickness ts of the rigid plate (tr / ts) is determined in the stacking direction according to the shear stiffness of the rubber plate and the shear stiffness of the plug in the height direction. The laminated rubber according to claim 1, wherein the laminated rubber is changed. 3. The laminated rubber according to claim 1, wherein a thickness ts of the rigid plate constituting the layer at both end portions in the laminating direction is formed thinner than a thickness ts of the rigid plate constituting the layer at the central portion in the laminating direction.