JP2017075476A - Expansion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an expansion device capable of preventing deformation of a seal layer.SOLUTION: An expansion device 10 for being provided at a girder end 27 of a bridge includes a pair of joints 12, and a seal layer 24 that is arranged to close a space between the joints 12. The pair of joints 12 has a surface part 14 on which irregularities protruding like teeth of a comb toward the other side are formed, and a support part 21A for preventing deformation of the seal layer 24 is fixed to the surface part 14.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a telescopic device, and more particularly, to a telescopic device provided at the end of a bridge girder.

  The telescopic device is provided at the end of the girder to absorb various displacements of the bridge, mainly the displacement of the length of the bridge girder caused by temperature changes in the environment. This telescopic device is required to have a function of maintaining flatness between the end portions of the girders and preventing permeation of rainwater and the like.

  As such an expansion / contraction device, a device including a pair of joints and a seal layer provided between the joints is disclosed (for example, Patent Document 1). In the said patent document 1, the sealing layer is prevented from jumping out on a road bridge by providing a pressing plate so as to cover the sealing layer.

JP 2004-100150 A

  However, the telescopic device according to Patent Document 1 is used in a cold region, and when the length of the bridge girder contracts, the gap between the girder ends widens, so that snow, earth and sand, etc. enter between the joints and pass further. There is a concern that the holding plate and the seal layer are deformed by the vehicle and the sealing performance is lowered.

  An object of this invention is to provide the expansion-contraction apparatus which can prevent a deformation | transformation of a seal layer.

  An expansion / contraction device according to the present invention includes a pair of joints and a seal layer disposed so as to close between the joints in the expansion / contraction device provided at the end of a bridge girder, and the pair of joints is connected to the other side. It has a surface portion on which irregularities projecting in a comb-tooth shape are formed, and a support portion for preventing deformation of the seal layer is fixed to the surface portion.

  According to the present invention, when snow is piled up in a state where the gap is widened and snow is pushed into the gap by a passing vehicle, the telescopic device acts on the tip of the support portion by fixing the support portion to the surface portion. Since the moment generated by the force applied can be reduced, it is possible to more reliably prevent the seal layer from being deformed by the snow pressure.

It is a perspective view which shows the whole structure of the expansion-contraction apparatus which concerns on this embodiment. It is a longitudinal cross-sectional view of the expansion-contraction apparatus which concerns on this embodiment. It is a top view of the support part which concerns on this embodiment. It is a top view of the expansion-contraction apparatus which concerns on this embodiment. It is a longitudinal cross-sectional view of the expansion-contraction apparatus which concerns on the modification (1) of this embodiment. It is a top view of the expansion-contraction apparatus which concerns on the modification (1) of this embodiment. It is a longitudinal cross-sectional view of the expansion-contraction apparatus which concerns on the modification (2) of this embodiment. It is a longitudinal cross-sectional view of the expansion-contraction apparatus which concerns on the modification (3) of this embodiment. It is a longitudinal cross-sectional view of the expansion-contraction apparatus which concerns on the modification (4) of this embodiment. It is a longitudinal cross-sectional view of the expansion-contraction apparatus which concerns on the modification (5) of this embodiment. It is a top view of a support part concerning modification (5) of this embodiment. It is a top view of the expansion-contraction apparatus which concerns on the modification (5) of this embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The telescopic device 10 </ b> A shown in FIG. 1 is made of steel and includes a pair of joints 12 having the same length as the width of the bridge girder and a plurality of anchor members 13 provided in the longitudinal direction of the joints 12.

  The joint 12 is made of an inverted L-shaped member, and has a surface portion 14 disposed on the bridge girder surface side, and a belly plate portion 16 formed integrally with the surface portion 14. The surface portion 14 is formed of a substantially rectangular plate member having the same length as the width direction (Y direction in the drawing) of the bridge girder, and one side surface in the longitudinal direction (hereinafter referred to as “tip”) is the surface portion on the other side. It arrange | positions so that the front-end | tip of 14 may be opposed.

  The tip of the surface portion 14 is repeatedly formed with irregularities protruding in a comb shape toward the other side. A gap 18 is formed between the tips of the surface portion 14. The gap 18 formed between the tips of the surface portion 14 is formed by combining the irregularities of the surface portion 14. That is, the concave formed on the surface portion 14 of the one joint 12 is paired with the convex formed on the surface portion 14 of the other joint 12, and the convex formed on the surface portion 14 of the one joint 12. , And is paired with a recess formed in the surface portion 14 of the other joint 12. By combining the unevenness formed on the surface portion 14 in this way, the gap 18 between the tips of the surface portion 14 is formed in a zigzag shape.

  The abdomen plate portion 16 is formed integrally with the base end of the surface portion 14 and is made of a plate member provided at a right angle to the surface portion 14. An anchor member 13 is provided on the outer surface of the abdominal plate portion 16. The anchor member 13 is made of a substantially rectangular plate member, and is provided so as to protrude in parallel with the bridge axis direction (X direction in the drawing) from the surface of the abdominal plate portion 16. The anchor member 13 protects the joint 12 from being damaged by the blade by guiding the blade of the snow removal grader to escape upward after installation.

  As shown in FIG. 2, the dust-proof layer 22, the support portion 21 </ b> A, the seal layer 24, and the backup layer 25 are arranged directly below the surface portion 14 between the pair of joints 12. . The dustproof layer 22 is made of an elastic foam such as EPDM foam. The foam is not only composed of open cells, but may also be a mixture of closed cells and open cells.

  The support portion 21 </ b> A is a rectangular plate member having the same length as the length of the joint 12 in the longitudinal direction, and is provided in each of the pair of joints 12 to prevent the seal layer 24 from being deformed. 21 A of support parts are being fixed to the lower surface of the surface part through the hexagon nut as the holding | maintenance part 23 with the countersunk | bolt bolt or a round head bolt although it is not illustrated. By using a flat head bolt or a round head bolt, the seal layer 24 can be prevented from being damaged.

  The seal layer 24 is formed so as to prevent rainwater and the like from penetrating the girder end 27 and to expand and contract following the expansion and contraction of the gap 18. The seal layer 24 can be formed of elastic rubber, stretchable foam, or the like.

  As shown in FIG. 3, the support portion 21 </ b> A has one longitudinal side surface (hereinafter referred to as “proximal end”) abutted against the abdominal plate portion, and the other longitudinal direction side surface (hereinafter referred to as “distal end”). A linear gap 28 is formed. The gap 28 formed by the support portion 21A is disposed substantially at the center of the zigzag gap 18 formed between the tips of the surface portion 14 (FIG. 4).

  The backup layer 25 is composed of a softer member than the seal layer 24 and can be formed of, for example, urethane foam. The backup layer 25 is supported on the lower surface by a receiving plate 26 fixed to the abdomen plate portion 16.

  The telescopic device 10A configured as described above is fixed to the end portion 27 of the bridge girder, with its longitudinal direction aligned with the width direction of the bridge girder. When the temperature decreases and the bridge girder contracts in the direction of the bridge axis, the clearance t (FIG. 2) between the girder ends 27 increases. As a result, in the telescopic device 10A fixed to the end portion 27, the gap 18 (28) is widened. When the clearance t between the beam ends 27 increases, the dust-proof layer 22 and the seal layer 24 disposed between the joints 12 extend following the expansion between the beam ends 27. Therefore, it is possible to prevent rainwater, dust, and the like that have entered the gap 18 from entering the beam end portion 27.

  Furthermore, when snow accumulates in the state where the gap 18 is widened, and the snow is pushed into the gap 18 by a passing vehicle, the telescopic device 10A receives the load caused by the snow on the support portion 21A disposed on the upper side of the seal layer 24. As a result, the seal layer 24 can be prevented from being deformed by snow pressure.

  In the case of the present embodiment, the support portion 21A is fixed to the lower surface of the surface portion 14 via the holding portion 23, so that the moment generated by the force acting on the tip of the support portion 21A can be reduced. Conventionally, since the support portion 21A is fixed to the abdominal plate portion 16 at the base end, the moment generated by the force acting on the tip increases when the base end is the origin. On the other hand, in the present embodiment, the support portion 21A is fixed to the surface portion 14, and the distance from the origin (in this case, the position of the holding portion 23) to the tip of the support portion 21A is shortened. Accordingly, the expansion device 10A can reduce the moment generated in the support portion 21A, and thus can more reliably prevent the deformation of the seal layer 24.

  Further, the linear gap 28 formed by the support portion 21A is disposed at the approximate center of the zigzag gap 18 formed between the tips of the surface portion 14, so that the gap 18 and the support portion of the surface portion 14 are supported. Since the overlap of the gaps 28 of 21A can be reduced, the expansion / contraction device 10A can more reliably prevent the seal layer 24 from being deformed.

  When the temperature rises and the bridge girder extends in the direction of the bridge axis, the clearance t between the girder ends 27 becomes narrower. As a result, in the telescopic device 10A fixed to the girder end 27, the gap 18 (28) is narrowed. When the clearance t between the spar end portions 27 is narrowed, the dustproof layer 22 and the seal layer 24 disposed between the joints 12 contract following the contraction between the spar end portions 27. When the seal layer 24 contracts, the backup layer 25 disposed on the lower side is deformed to the lower side because the backup layer 25 is made of a softer member than the seal layer. That is, the backup layer 25 provided on the lower side of the seal layer 24 absorbs the deformation of the lower side of the seal layer 24. Thereby, in the expansion / contraction device 10A, the seal layer 24 does not protrude from the gap 18 of the surface portion 14 of the joint 12 to the surface of the bridge girder.

  Since the support portion 21 </ b> A is disposed below the dust-proof layer 22, the support portion 21 </ b> A is not visually recognized from the gap 18 formed between the tips of the surface portion 16. Therefore, the telescopic device 10A can improve the external appearance since the support portion 21A is not visually recognized from the outside.

(Modification)
The present invention is not limited to the above-described embodiment, and can be appropriately changed within the scope of the gist of the present invention. For example, in the above embodiment, the support portion 21A has been described with respect to the case where the gap 18 is formed between the tips, but the present invention is not limited to this.

  The telescopic device 10B according to the modification (1) shown in FIG. 5 is different from the above embodiment in the configuration of the support portion 21B. The support portion 21B is formed so that the tip portion overlaps in the thickness direction. In this case, by appropriately changing the lengths of the holding portion 23 that holds one support portion 21B and the holding portion 23 that holds the other support portion 21B, the tip portion of the support portion 21B overlaps in the thickness direction. Can be held. The telescopic device 10B provided with such a support portion 21B can completely cover the seal layer 25 with the support portion 21B against the gap 18 formed between the tips of the surface portion 14 (FIG. 6). The telescopic device 10B according to the present modification can obtain the same effect as that of the above embodiment by fixing the support portion 21B to the surface portion 14 via the holding portion 23.

  The length at which the tip portion of the support portion 21B overlaps can be set as appropriate, but is preferably set so as to keep the overlap even when the clearance t between the beam end portions 27 is maximized. By doing so, the seal layer 24 can always be covered with the support portion 21B, so that the deformation of the seal layer 24 can be more reliably prevented even when the clearance t is maximized, that is, when snow pressure is caused by snowfall. be able to.

  Further, as in the expansion / contraction device 10 </ b> C according to the modification (2) shown in FIG. 7, the support portion 21 </ b> C is attached to the first support portion 30 fixed to the holding portion 23 and the distal end portion of one first support portion 30. It is good also as comprising with the 2nd support part 31 fixed. The second support portion 31 is fixed to one of the first support portions 30 by welding or the like at the base end, and is provided so as to overlap the tip portion of the other first support portion 30 in the thickness direction at the tip end. . In this case, unlike the modification (1), the holding part 23 provided between the first support part 30 and the surface part 14 can be shared. Since the second support portion 31 is provided at the tip so as to overlap the tip portion of the other first support portion 30 in the thickness direction, it is possible to obtain the same effect as in the modification (1).

  The expansion / contraction device 10D according to the modification (3) shown in FIG. 8 is different from the modification (2) only in the configuration of the support portion 21D. The support portion 21D according to this modification includes a first support portion 30 fixed to the holding portion 23, and a second support portion fixed to the tip portion of one of the first support portions 30 via the interval holding portion 32. 31. One first support portion 30 and the interval holding portion 32, and the interval holding portion 32 and the second support portion 31 can be fixed by welding. By fixing the second support portion 31 through the interval holding portion 32 in this way, a gap is provided in the thickness direction between the second support portion 31 and the tip portion of the other first support portion 30. ing. As a result, when the telescopic device 10D is installed in a state inclined in the bridge axis direction, even if the beam end 27 moves in the rotation direction due to the bridge girder extending and contracting in the bridge axis direction, It is possible to prevent the second support portion 31 from interfering.

  The interval holding unit 32 may use a hex nut 33 as in the expansion and contraction device 10E according to the modification (4) shown in FIG. One first support portion 30 and hex nut 33 can be fixed by welding, and hex nut 33 and second support portion 31 can be fixed by a countersunk screw or a round head bolt (not shown). The support portion 21 </ b> E is spaced in the thickness direction between the second support portion 31 and the tip portion of the other first support portion 30. Thereby, the expansion-contraction apparatus 10E can acquire the effect similar to the said modification (3).

  Moreover, in the case of the said embodiment, although 21 A of support parts demonstrated the case fixed to the surface part 14 via the holding | maintenance part 23, this invention is not limited to this. In the telescopic device 10F according to the modification (5) shown in FIG. 10, the support portion 21F is directly fixed to the lower surface of the surface portion 14. The means for directly fixing the support portion 21F to the surface portion 14 is not particularly limited. For example, the support portion 21F may be fixed by welding, or a tapped hole may be formed in the surface portion 14 and fixed by a countersunk bolt or a round head bolt. It is good. As shown in FIG. 11, the support portion 21 </ b> F is a plate member having the same length as the longitudinal length of the joint 12, and the tip is flat and the protrusions and recesses protruding in a comb shape are repeatedly formed at the base end. Has been. The support portion 21F is fixed by aligning the unevenness formed at the base end with the unevenness formed on the surface portion 14 (FIG. 12). As a result, in the expansion / contraction device 10F, the seal layer 24 is covered with the support portion 21F leaving the central portion of the gap 18 formed between the tips of the surface portion 14. The telescopic device 10F according to the present modification can obtain the same effects as those of the above-described embodiment by fixing the support portion 21F to the surface portion 14. Moreover, since the expansion | extension apparatus 10F decided to fix the support part 21F directly to the surface part 14, since the holding | maintenance part 23 can be abbreviate | omitted, the number of parts can be reduced by that much compared with the said embodiment. .

  In the case of the said embodiment, although 21 A of support parts demonstrated the case where a front-end | tip was flat, this invention is not restricted to this, It is good also as forming the unevenness | corrugation which protruded in the comb-tooth shape at the front-end | tip.

10A, 10B, 10C, 10D, 10E, 10F Telescopic device 12 Joint 14 Surface portion 18 Gap 21A, 21B, 21C, 21D, 21E, 21F Support portion 22 Dustproof layer 24 Seal layer 27 Girder end portion 28 Gap

Claims (5)

In a telescopic device provided at the end of a bridge girder,
A pair of joints;
A seal layer disposed so as to block between the joints,
The pair of joints has a surface portion formed with concavities and convexities protruding in a comb-tooth shape toward the other side,
A telescopic device, wherein a support portion for preventing deformation of the seal layer is fixed to the surface portion. The telescopic device according to claim 1, wherein the support part is fixed to the surface part via a holding part. The expansion / contraction apparatus according to claim 2, wherein a dustproof layer is formed between the surface portion and the support portion. The telescopic device according to any one of claims 1 to 3, wherein the support portion is formed such that tips thereof overlap in the thickness direction. The telescopic device according to claim 4, wherein the ends of the support portions are spaced in the thickness direction.

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