JP2007262712A - Expansion joint for bridge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an expansion joint for a bridge, which has a high-hardness rubber formed therein in one body and a cushioning mechanism built therein. <P>SOLUTION: The expansion joint 10 for the bridge is formed of a pair of side plate cored bars 11 secured to floor slabs by anchor bolts, respectively, and a bottom plate cored bar 12 extending in an expansion gap. Each side plate cored bar 11 is secured to a bottom surface of a shearing rubber layer 131, and the bottom plate cored bar 12 is secured to a bottom surface of a shearing rubber layer 132. The side plate cored bars 11, the bottom plate cored bar 12, and a shear deformation 13 are formed of a first rubber member in one body as a whole. Further a cushioning section 16 formed of a high-hardness second rubber member, which is formed in one body with the first rubber member, is arranged on a lower side of the bottom plate cored bar 12 under the shear rubber layer 132. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a telescopic device installed between bridges or between a bridge and an abutment. In particular, the present invention relates to an expansion joint that is attached to a gap between bridges such as road bridges and viaducts.

  An expansion joint is generally installed between the bridges. For example, on a road bridge, a load-supporting expansion joint is often used because the vehicle travels on the expansion joint. As a load-supporting expansion joint, the bottom plate core metal is bridged between the gaps, both ends of the bottom plate core metal are held by the shear rubber layer, and the side plate core metal mounted on the shear rubber layer is anchored to the floor slab. A rubber joint type expansion joint for fixing is known. In rubber joint type expansion joints, the load applied to the gap is supported by both bridges via the bottom metal core spanned between the gaps, and fluctuations between the bridges across the gap are absorbed by the deformation of the shear rubber layer. The

2. Description of the Related Art In a rubber joint type expansion joint, a configuration is known in which two shear rubber layers are connected in series to both ends of a bottom metal core in order to increase the amount of expansion and contraction. However, in such a configuration, since the shear rubber layer to which the bottom plate core is connected is not fixed to the floor slab, the bottom plate core is struck against the floor slab when passing through the vehicle and a running sound is generated. Therefore, conventionally, rubber is laid under the bottom metal core connected to the shear rubber layer to reduce running noise (Patent Document 1).
Japanese Patent Laid-Open No. 5-86604

  However, in the configuration described in Patent Document 1, it is necessary to secure a space for the cushioning rubber, and it is necessary to take measures to prevent the cushioning rubber from dropping into the idler portion. Is disadvantageous in terms of

  An object of the present invention is to provide a bridge expansion joint with a built-in buffer mechanism.

  The expansion joint for a bridge according to the present invention is an expansion joint for a bridge that is installed between the bridges, and the second rubber member for buffering is integrally formed with the first rubber member constituting the expansion joint body. It is characterized by.

The hardness of the first rubber member is 45 degrees to 65 degrees, and the hardness of the second rubber member is 70 degrees to 90 degrees. The second rubber member has a flow (Q) under the test conditions of 150 ° C. constant temperature method, die φ1 mm × L2 mm, preheating 150 ° C. × 3 minutes, surface pressure 80 kgf / cm ² , Q = 15 × 10 ⁻ It is a rubber of ³ cm ³ / s or more, and in the measurement of a vulcanization curve according to JIS K6300-2, the vulcanization start point tc (10) is preferably 7 minutes or more.

  The expansion joint for bridges is provided with a gap construction part installed between the gaps, and a shear deformation part at both ends of the gap construction part, which deforms as the gap expands and contracts. A buffer portion formed of the second rubber member is integrally formed on the bottom surface of the shear deformation portion.

  The shear deformation portion includes a first shear rubber layer fixed to the floor slab, and a second shear rubber layer fixed to the bottom metal core embedded in the idler laying portion, and the buffer portion is the second shear rubber The layer is integrally formed below the bottom plate core.

  As described above, according to the present invention, it is possible to provide a bridge expansion joint with a built-in buffer mechanism.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a side sectional view of a bridge expansion joint 10 according to an embodiment of the present invention.

  The expansion joint 10 for a bridge according to the present embodiment includes a pair of side plate cores 11 fixed to a floor slab with anchor bolts, a bottom plate core 12 that is disposed substantially at the center of the bridge expansion joint 10 and spans a gap. The bottom plate core metal 12 and the side plate cores 11 on both sides are connected to each other, and are composed of a pair of shear deformation portions 13 that expand and contract the bridge expansion joint 10 by deformation of the rubber layer. The shear deformation portion 13 is integrally formed of the first rubber member as a whole.

  Moreover, the shear deformation part 13 is comprised from a pair of shear rubber layers 131 and 132, respectively, and the shear rubber layers 131 and 132 are connected by the top-plate metal core 14 embedded in the 1st rubber member. That is, as shown in FIG. 1, the bottom surface of the shear rubber layer 131 is fixed to the side metal core 11, and the bottom surface of the shear rubber layer 132 is fixed to the bottom metal core 12. On the other hand, the top metal core 14 is installed on the upper side of the shear rubber layers 131 and 132, and the load applied between the two shear rubber layers 131 and 132 is supported by the shear rubber layers 131 and 132.

  Both ends of the bottom metal core 12 are connected to the bottom surface of the shear rubber layer 132, respectively, but the center rises upward to form a flat portion and is laid between the play. The bottom metal core 12 is embedded in the first rubber member of the idler laying portion 15. In the shear rubber layer 132, the lower side of the bottom metal core 12 is formed by the second rubber member and constitutes the buffer portion 16. Accordingly, the load applied to the bottom plate core 12 is supported by the buffer portion 16.

  Grooves are provided between the shear rubber layer 131, the shear rubber layer 132, and the free span framing portion 15, and the shear rubber layers 131 and 132 can be subjected to shear deformation. That is, the expansion joint 10 for a bridge can be expanded and contracted freely by expansion and contraction by deformation of the shear rubber layers 131 and 132.

  FIG. 2 is an enlarged side sectional view showing a state in which the bridge expansion joint 10 is installed on the floor slab, and only the right half of the bridge expansion joint 10 in FIG. 1 is shown. The same applies to the left half.

  A step 21 for installing the bridge expansion joint 10 is provided at the end of the floor slab 20, and the side plate core 11 and the shear deformation portion 13 of the bridge expansion joint 10 are located on the step 21. Is mounted via a reinforcing plate 22. An anchor member 23 is embedded in the stepped portion 21, and the side plate core 11 is fixed to the anchor member 23 using a fixing means such as a bolt, whereby the side plate core 11 and the shear rubber layer 131 are floor slabs. 20 is fixed.

  On the other hand, the bottom surface of the buffer portion 16 constituting the lower side of the shear rubber layer 132 is slidable with respect to the reinforcing plate 22 only by being placed on the reinforcing plate 22. That is, the shearing rubber layers 131 and 132 are deformed by the buffer portion 16 sliding on the reinforcing plate 22 in accordance with expansion and contraction during play.

  Further, since the bottom surface of the buffer portion 16 is not constrained by the reinforcing plate 22, even when the bottom plate core 12 is struck against the floor slab 20 by traveling of the vehicle, the shock is absorbed by the buffer portion 16 and the noise is reduced. As well as improving the durability of the expansion joint 10 for bridges.

  In the present embodiment, the buffer portion 16 is formed integrally with the shear rubber layer 132. The shear rubber layers 131 and 132 and the free span erection portion 15 are formed of the first rubber member. However, since the shear rubber layers 131 and 132 need to be deformed following the expansion and contraction of the free space, the first rubber is used. For the member, rubber having a hardness of 45 to 65 degrees (more preferably, a hardness of 50 to 55 degrees) is used. In the present specification, the hardness is a value based on JIS K6253-1997 Type A.

  On the other hand, the second rubber member of the buffer portion 16 is made of high hardness rubber having a hardness of 70 to 90 degrees (preferably, a hardness of 90 degrees), for example, from the viewpoint of impact buffering and durability. However, generally, as the hardness of the rubber increases, the flow of the rubber becomes worse and the time to the vulcanization start point tc (10) tends to be shorter. Therefore, as in the present embodiment, it has been difficult in the past to integrally form the first rubber member and the second rubber member having greatly different hardness due to problems such as the occurrence of a lack of thickness. In particular, since the buffer portion is the portion that contacts the hot plate earliest in molding, the time difference until the vulcanization start point tc (10) between the first rubber member and the second rubber member is further increased. It was extremely difficult to form the part 16 integrally with the shearing part 13.

  In this specification, the vulcanization start point tc (10) is based on JIS K6300-2 2001, and the torque of the vulcanization curve is (maximum value−minimum value) × 10% + minimum value. It's time.

  In the present embodiment, by selecting a high-hardness rubber having the characteristics described below as the second rubber member, the buffer portion 16 is formed integrally with the first rubber member without causing problems such as the occurrence of a lack of thickness. Made it possible to do.

That is, the second rubber member has a flow (Q) under the test conditions of 150 ° C. constant temperature method, die φ1 mm × L2 mm, preheating 150 ° C. × 3 minutes, surface pressure 80 kgf / cm ² , Q = 15 A rubber of × 10 ⁻³ cm ³ / s or more is used. Further, the vulcanization start point tc (10) of the second rubber member is 7 minutes or more.

  As described above, according to this embodiment, a rubber member having a high hardness can be integrally formed on the rubber member constituting the expansion joint body for a bridge, and an expansion joint for a bridge having a built-in buffer mechanism can be obtained. Can do.

It is a sectional side view of the bridge expansion joint which is one Embodiment of this invention. It is a partial expanded side sectional view when the bridge expansion joint shown by FIG. 1 is installed in a floor slab.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Expansion joint for bridges 11 Side plate metal core 12 Bottom plate metal core 13 Shear deformation part 14 Top plate metal core 15 Free span installation part 16 Buffer part 20 Floor slab 21 Step part 22 Reinforcement plate 23 Anchor member 131 Shear rubber layer 132 Shear rubber layer

Claims (5)

  An expansion joint for bridges constructed between the bridges, wherein the second rubber member for buffering is integrally formed with the first rubber member constituting the expansion joint main body.   The expansion joint for a bridge according to claim 1, wherein the hardness of the first rubber member is 45 degrees to 65 degrees, and the hardness of the second rubber member is 70 degrees to 90 degrees. The second rubber member has a flow (Q) of Q = 15 × 10 under the test conditions of 150 ° C. constant temperature method, die φ1 mm × L2 mm, preheating 150 ° C. × 3 minutes, surface pressure 80 kgf / cm ^2. It is rubber | gum more than ^-3 cm < ³ > / s, In the measurement of a vulcanization curve according to JISK6300-2, vulcanization | cure start point tc (10) is 7 minutes or more, It is characterized by the above-mentioned. Expansion joints for bridges.   The bridge expansion joint includes an idle span erected between the gaps, and a shear deformer at both ends of the gap erection and deforms as the gap expands and contracts, and the shear deformer on the floor slab The expansion joint for a bridge according to claim 1, wherein a buffer portion fixed and formed by the second rubber member for buffering is integrally formed on a bottom surface of the shear deformation portion.   The shear deformation portion includes a first shear rubber layer fixed to the floor slab, and a second shear rubber layer fixed to a bottom metal core embedded in the idle span linking portion, and the buffer portion is the The expansion joint for bridges according to claim 4, wherein the expansion joint for a bridge according to claim 4 is integrally formed below the bottom plate core metal in the second shear rubber layer.

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