JP2023092030A - Bridge expansion device - Google Patents

Abstract

An object of the present invention is to provide a bridge expansion/contraction device that is easy to maintain and repair, and that can significantly reduce the life cycle cost (LCC) of a bridge.
A bridge expansion and contraction device of the present invention includes a base web 10 having two base bodies 11, a plurality of connecting portions 12 and a plurality of stud bolts 14, and a plurality of face plates having bolt holes 23 communicating between both surfaces. 20, a water-permeable filter sheet 30, a backup material 40, a water-impermeable elastic sealing material 50, and a water collecting space 60 defined by the two base bodies 11, the filter sheet 30 and the elastic sealing material 50. .
[Selection drawing] Fig. 1

Description

Applied for application of Article 30, Paragraph 2 of the Patent Act Published in Fukui Shimbun on February 4, 2021. Published in the Fukui Shimbun on October 6, 2021. Published in Kensetsu Kogyo Shimbun on January 20, 2021. Published in Kensetsu Kogyo Shimbun on October 8, 2021. Published in Kensetsu Kogyo Shimbun on December 1, 2021. Presented at the Fukui Prefecture Next-Generation Bridge Material Commercialization Study Group on March 30, 2021. Presented at the Fukui Prefecture Road Maintenance Workshop on August 30, 2021. Announced at the 2021 Fukui Prefectural Industrial Technology Center open to the public on November 25 and 26, 2021. Announced at the Fukui Construction Technology Fair 2021 on September 8th and 9th, 2021. Published on the website on August 23, 2021. Published on the website on December 23, 2020. Published on the website on January 14, 2021. Constructed on October 4th and 5th, 2021 at Tenjinbashi in Shinoocho, Fukui City, Fukui Prefecture.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bridge expansion device, and more particularly to a bridge expansion device that is easy to maintain and repair, and that can greatly reduce the life cycle cost (LCC) of a bridge.

Currently, there are more than 700,000 bridges in Japan, of which about 23% as of 2017 are aging bridges that have passed 50 years since construction. This proportion is expected to reach about 50% in 10 years and about 70% in 20 years.
Many of the existing bridges have deteriorated in soundness due to fatigue damage, salt damage, neutralization, etc. due to the increase in vehicle size and traffic volume.

One of the causes of damage to bridges is water leakage from bridge expansion devices to abutments and piers. A bridge expansion/contraction device is a device installed between a bridge girder and an abutment to absorb expansion and contraction of the bridge caused by temperature changes, vehicle traffic, earthquakes, and the like.
Leakage from bridge expansion devices to abutments and piers causes corrosion of steel girder ends and bearings, and rapid deterioration of abutment concrete due to frost damage and salt damage. Especially in cold regions, anti-freezing agents are often sprayed on the road surface, and chlorides eluted from the anti-freezing agents are mixed into the leaked water, causing rapid corrosion of steel members.
As a conventional bridge expansion/contraction device, Patent Document 1 discloses a finger joint type bridge expansion/contraction device in which a water stop material is arranged in a supporting portion integrally provided under a comb tooth-shaped face plate. Further, Patent Document 2 discloses a rubber-made secondary water stop device provided under the water stop material in this bridge expansion and contraction device.

JP 2004-143845 A Utility Model No. 3174898

The prior art has the following problems.
<1> Since the water stop material is positioned directly below the face plate, if foreign matter such as sand or snow enters between the face plates, the water stop material may be pushed downward and damaged.
<2> Since the faceplate is integral with the web, the water stop material under the faceplate cannot be inspected/repaired from the bridge. For this reason, after the water stoppage material is damaged, the water is stopped by the secondary water stoppage device installed below the water stoppage material, and repairs are started after the secondary water stoppage device is damaged. Therefore, during repairs, water remains inside the bridge expansion joints for a long period of time, causing extensive damage to the entire bridge expansion joints. may also be damaged.
<3> It is not possible to repair/replace the faceplate or the water stop material below it for each part. For this reason, when repairing, it is necessary to scrape off the concrete on the bridge surface and replace the entire bridge expansion device (Fig. 6), which increases the repair cost. In addition, since the scale of the repair work is large, it is necessary to stop traffic for a long time, which has a great impact on the traffic in the neighborhood.
<4> Preventive maintenance, such as inspection of water stopping materials and removal of foreign matter under the faceplate, is difficult, and post-failure maintenance after damage is the main focus, increasing the life cycle cost (LCC) of the bridge.

SUMMARY OF THE INVENTION An object of the present invention is to provide a bridge expansion/contraction device for solving the above problems.

The bridge expansion and contraction device of the present invention comprises two base bodies that extend substantially parallel across an expansion slit, and a plurality of joints that fix the two base bodies in the bridge girder and abutment or in the filling concrete of the two bridge girders, respectively. and a plurality of stud bolts projecting upward from the upper surface of one of the base bodies. A base web having bolt holes communicating with both sides and covering the upper part of the expansion slit along the longitudinal direction of the base body. a plurality of face plates arranged on the base body so as to be water permeable, and a water permeable structure provided on the base body so as to close the upper part of the expansion slit along the longitudinal direction of the base body at the lower part of the plurality of face plates a filter sheet, a backup material sandwiched between the two base bodies over the entire length of the stretchable slit, a water-impermeable elastic sealing material placed on the backup material over the entire length of the stretchable slit, and two base bodies , a filter sheet, and a water collecting space defined by an elastic sealing material, and a plurality of face plates are formed by inserting stud bolts into the bolt holes of the plurality of face plates and screwing nuts onto the stud bolts. is fixed to one of the base bodies.

In the bridge expansion and contraction device of the present invention, the base body may be provided with an arrangement groove having a depth corresponding to the thickness of the filter sheet on the upper surface.

In the bridge expansion/contraction device of the present invention, the filter sheet may have slack toward the water collecting space at the designed maximum width of the expansion/contraction slit.

In the bridge expansion and contraction device of the present invention, the face plate may have a two-layer structure of a support plate covering the upper part of the base body and a protection plate covering the surface of the support plate.

In the bridge stretching device of the present invention, the filter sheet may be made of a water-permeable sheet made of high-strength polyester fiber.

In the bridge expansion device of the present invention, the base web may have a plurality of guiding portions extending from the height of the upper edge of the base body in the direction of the bridge girder and/or abutment.

Since the bridge expansion and contraction device of the present invention has the above configuration, it has at least one of the following effects.
<1> By covering the upper part of the elastic sealing material with a filter sheet and securing a water collection space between the elastic sealing material and the filter sheet, foreign matter is captured by the filter sheet, and the water stopping function is achieved by pushing the foreign matter into the filter sheet. Damage can be prevented.
<2> By making the face plate detachable, the inside of the bridge expansion/contraction device can be easily inspected/repaired from the bridge. Therefore, since the primary water stop function can be restored at any time, there is no need to install a secondary water stop device.
<3> Repair costs can be reduced because the faceplate can be removed and the faceplate, the elastic sealing material, and the like can be repaired for each part. In addition, since repair work can be done in a short period of time, the impact of traffic restrictions on nearby traffic is small.
<4> Since the internal filter sheet and elastic sealing material can be inspected/repaired at any time from the bridge, the LCC of the bridge can be greatly reduced through preventive maintenance.

Explanatory drawing of the bridge expansion-contraction apparatus which concerns on this invention. Explanatory drawing of the base web. Explanatory drawing of a faceplate. Explanatory drawing of a filter sheet. Explanatory drawing of the maintenance of a bridge expansion-contraction apparatus. Drawing substitute photograph which concerns on a prior art.

Hereinafter, the bridge expansion/contraction device of the present invention will be described in detail with reference to the drawings.

[Bridge expansion device]
<1> Overall configuration (Fig. 1)
The bridge expansion/contraction device 1 of the present invention is a load-bearing and slide joint type expansion/contraction device installed between a bridge girder and an abutment or between two bridge girders.
The bridge expansion/contraction device 1 as a whole has a long shape elongated in the width direction of the bridge girder.
The bridge expansion device 1 includes a base web 10 connected to a bridge girder and abutment or two bridge girders with an expansion slit S interposed therebetween, a plurality of face plates 20 arranged on the base web 10 and covering the upper part of the expansion slit S, A filter sheet 30 blocking the upper part of the expandable slits S under a plurality of face plates 20, a backup material 40 sandwiched in the expandable slits S, an elastic seal material 50 placed on the backup material 40, and in the expandable slits S At least a water collecting space 60 defined between the filter sheet 30 and the elastic sealing material 50 is provided.

<2> Base web (Fig. 2)
The base web 10 is the basic structural member of the bridge expansion device 1 .
The base web 10 is mainly composed of two elongated base bodies 11 arranged substantially in parallel. A telescopic slit S is configured between two base bodies 11 .

<2.1> Base body (Fig. 2)
The base body 11 is a member that supports the faceplate 20 .
The base body 11 includes at least a plurality of connecting portions 12 for fixing in interstitial concrete such as a bridge girder, and a plurality of stud bolts 14 provided on the upper surface of one of the base bodies 11 .
In this example, the base body 11 includes a long horizontal portion 11a, a clamping wall 11b extending downward from one widthwise side of the horizontal portion 11a, and an upwardly extending side from the other widthwise side of the horizontal portion 11a. A steel material having a stepped cross-section is adopted.
The two base bodies 11 are combined so that the holding wall 11b faces inward.
A support fitting for supporting the backup material 40 from below is attached to the inner side of each clamping wall 11b (not shown).
The stud bolts 14 are provided at regular intervals along the longitudinal direction of the horizontal portion 11a.

<2.2> Connection part (Fig. 2)
The connecting portion 12 is a fixing member of the base body 11 .
In this example, as the connecting portion 12, a deformed reinforcing bar welded to the outer surface of the holding wall 11b at predetermined intervals along the longitudinal direction of the holding wall 11b is employed.
When installing or exchanging the bridge expansion/contraction device 1, the base body 11 is fixed to the bridge girder or abutment by arranging the connecting part 12 in the placing space of the bridge girder or the abutment and pouring filling concrete.
The connection portion 12 is not limited to the above configuration, and may be other known fixing members such as a headed stud dowel, a perforated steel plate dowel, an exchange penetration type perforated steel plate dowel, and a hoop reinforcing bar. Further, the attachment position of the connecting portion 12 is not limited to the clamping wall 11b, and may be provided outside the housing wall 11c, for example.
In short, any structure may be employed as long as the base body 11 can be securely fixed to the bridge girder or abutment.

<2.3> Induction section (Fig. 2)
The guide portion 13 is a member for preventing damage to the base body 11 and the faceplate 20 .
In this example, as the guiding portion 13, a member made of steel provided outside the housing wall 11c and extending outward from the height of the upper edge of the housing wall 11c is employed.
Especially in the Hokuriku and Tohoku regions where snowfall is heavy, there have been many accidents where the blades of snowplows during work come into contact with the expansion and contraction devices of bridges, damaging the base and faceplates. Therefore, a guiding portion 13 is provided on the outside of the base body 11, and the top surface of the guiding portion 13 guides the teeth of the running snowplow upward, so that the teeth of the snowplow collide with the base body 11 and the face plate 20. to prevent damage.

<2.4> Alignment groove (Fig. 4)
The arrangement groove 11d is a step for accommodating the filter sheet 30. As shown in FIG.
In this example, the upper surface of the base body 11 is provided with an arrangement groove 11 d having a depth corresponding to the thickness of the filter sheet 30 .
Specifically, in the horizontal portion 11a of the base body 11, the corner on the side of the expansion slit S is notched along the longitudinal direction of the base body 11 to provide a horizontal arrangement groove 11d.
The depth of the arrangement groove 11 d corresponds to the thickness of the filter sheet 30 . Here, "corresponding to" does not necessarily have to be the same as the thickness of the filter sheet 30, but at least the upper part of the filter sheet 30 protrudes above the horizontal portion 11a so that there is a gap between the face plate 20 and the horizontal portion 11a. It means that the depth is such that it does not occur.
The arrangement groove 11 d can prevent the filter sheet 30 from being turned up or peeled off due to expansion and contraction of the face plate 20 .

<3> Faceplate (Fig. 3)
The face plate 20 is a member that covers the upper part of the expansion slit S. As shown in FIG.
The face plates 20 are arranged in parallel along the longitudinal direction of the base body 11 .
In this example, as the face plate 20, a combination of a protection plate 21 made of a rectangular checkered steel plate and a support plate 22 made of a rectangular steel plate narrower than the protection plate 21 is adopted. Welded together.
The faceplate 20 has a plurality of bolt holes 23 through which the stud bolts 14 of the base web 10 are inserted.
The position of each bolt hole 23 corresponds to the position of the stud bolt 14 when the faceplate 20 is installed on the base web 10 . A small step is provided in the bolt hole 23 to support and fix with the nut 15 .
The face plate 20 is placed on the horizontal portion 11a of the base body 11, and the nuts 15 are screwed onto the stud bolts 14 in the bolt holes 23, so that the nuts 15 support the small steps in the bolt holes 23, and the face plate is mounted. 20 can be fixed to the base body 11 .
After the nut 15 is screwed, the bolt hole 23 is filled with a filler 16 such as resin for sealing.

<3.1> Two-layer structure of face plate (Fig. 3)
In this example, the face plate 20 has a two-layer structure of a support plate 22 covering the upper portion of the base body 11 and a protection plate 21 covering the surface of the support plate 22 .
For this reason, the protective plate 21, which requires surface treatment, such as a checkered steel plate, is a common member with a constant thickness, and the thickness of the support plate 22, which requires little processing and is easy to obtain, is set to the face plate 20 in terms of structural calculation. It is possible to respond to various thicknesses required for at low cost.

<4> Filter sheet (Fig. 4)
The filter sheet 30 is a member having a function of catching foreign matter D that has entered under the face plate 20 . Here, "foreign matter" includes earth and sand, snow, antifreeze, plants, dust, garbage, and the like.
The filter sheet 30 is made of a water-permeable material. In this example, as the filter sheet 30, a water-permeable sheet made of high-strength polyester fiber having high tensile strength and excellent weather resistance is employed.
The filter sheet 30 is attached along the arrangement groove 11d of the base body 11 between the two horizontal portions 11a so as to block the upper portion of the expandable slit S. As shown in FIG.
Specifically, for example, a band-shaped filter sheet 30 is adhered continuously along the base body 11 and inside the arrangement groove 11d. Alternatively, a plurality of filter sheets 30 may be adhered so that their ends overlap each other.
In this example, a dust collector 31 is provided on the top surface of the filter sheet 30 .

<4.1> Dust collector (Fig. 4)
The dust collector 31 has a structure for holding the foreign matter D. As shown in FIG.
The dust collecting part 31 is configured on the filter sheet 30 by loosening the center of the filter sheet 30 toward the water collecting space 60 side.
More specifically, the filter sheet 30 is installed with a width that slackens toward the water collecting space 60 at the center of the design maximum width of the stretchable slit S, and the dust collection part 31 is configured at the upper center of the filter sheet 30 .
When the foreign matter D is pushed into the lower part of the face plate 20 from the road surface due to the passage of vehicles or the expansion and contraction of the expansion slit S, the foreign matter D accumulates in the dust collecting portion 31 recessed toward the water collecting space 60 side, and the filter sheet 30 can be prevented from being pushed and broken.

<5> Backup material (Fig. 4)
The backup material 40 is a member that supports the elastic sealing material 50 .
The backup material 40 has elasticity that can follow the expansion and contraction of the expansion and contraction slit S.
In this example, as the backup material 40, urethane foam having an elongated shape with a rectangular cross section is used. However, the material of the backup material 40 is not limited to this, and may be made of foamed polyethylene resin, for example.
The backup material 40 is pushed over the entire length of the expansion slit S between the two clamping walls 11b and placed on the support fitting.

<6> Elastic sealing material (Fig. 4)
The elastic sealing material 50 is a member having a water stop function.
The elastic sealing material 50 is made of a water-impermeable material.
In this example, as the elastic sealing material 50, a two-component sealing material containing a polybutadiene-based liquid as a main component is employed. In this example, the main agent is filled on the backup material 40 with the backup material 40 sandwiched between the two holding walls 11b. Mold integrally on 40.
However, the elastic sealing material 50 is not limited to polybutadiene, and may be made of other raw materials. In addition, the sealing material is not limited to the two-component type, and may be a dry sealing material formed by integrating an open-cell foam and a waterproof film.

<7> Separation of water stop function and dust collection function (Fig. 4)
One of the features of the bridge expansion/contraction device 1 of the present invention is that the combination of the elastic sealing member 50 and the filter sheet 30 separates the water stopping function and the dust collecting function.
In the conventional bridge expansion and contraction device, since the water stoppage material is installed directly under the faceplate, foreign matter such as earth and sand or pressure contact snow that enters the lower part of the faceplate pushes the waterstop material downward, causing water stoppage. There is a risk that the material will fall off or be damaged, impairing the waterproof function.
On the other hand, in the bridge expansion/contraction device 1 of the present invention, the elastic sealing material 50 is arranged at the back of the expansion/contraction slit S, and the water collecting space 60 is secured between the filter sheet 30 and the elastic sealing material 50, thereby While the filter sheet 30 catches the foreign matter D that has entered the lower part of the filter 20, only water is filtered and dropped into the water collecting space 60.例文帳に追加As a result, it is possible to prevent the elastic sealing material 50 from coming off or being damaged by the foreign matter D, and to ensure the water stopping function.

<8> Maintenance of bridge expansion device (Fig. 5)
One of the features of the bridge expansion/contraction device 1 of the present invention is that after installation and use, the faceplate 20 can be removed from the base web 10 and the inside of the expansion slit S can be maintained (maintained and repaired) from above the bridge.
In detail, for example, maintenance is performed according to the following procedure.
The filler 16 is peeled off from the bolt hole 23 of the protection plate 21, and the nut 15 is loosened and removed from the stud bolt 14. - 特許庁
The faceplate 20 is lifted and removed from the base body 11. - 特許庁Similar operations are performed for all faceplates 20 . At this time, since the faceplate 20 is not a single piece, but a divided body continuous in the longitudinal direction of the base body 11, the faceplate 20 is lightweight and can be removed by the worker alone.
By removing the faceplate 20, the horizontal portion 11a of the base body and the filter sheet 30 are exposed.
Here, if the filter sheet 30 is not damaged, the foreign matter D cannot enter the water collecting space 60, so it can be confirmed that the water stopping function of the elastic sealing member 50 is not impaired. In this case, the maintenance is completed only by cleaning the foreign matter D on the filter sheet 30 .
On the other hand, if the filter sheet 30 is damaged or if the elastic sealant 50 needs to be visually checked, the elastic sealant 50 is exposed by removing the filter sheet 30 from the horizontal portion 11a. It can be checked and repaired if necessary.

Reference Signs List 1 bridge expansion device 10 base web 11 base body 11a horizontal portion 11b holding wall 11c accommodation wall 11d placement groove 12 connecting portion 13 guiding portion 14 stud bolt 15 nut 16 filler 20 face plate 21 protection plate 22 support plate 23 bolt hole 30 filtration Sheet 31 Dust collecting part 40 Backup material 50 Elastic sealing material 60 Water collecting space S Expandable slit D Foreign matter

Claims (6)

A bridge expansion device installed between a bridge girder and an abutment or between two bridge girders,
Two base bodies extending substantially parallel to each other with an expansion/contraction slit interposed therebetween, a plurality of joints for fixing the two base bodies respectively in a bridge girder and abutment or in filling concrete of the two bridge girders, and one of the base bodies a base web having a plurality of stud bolts projecting upwardly from the top surface of the
a plurality of face plates having bolt holes communicating with both sides and arranged on the base body so as to cover the upper part of the expansion slit along the longitudinal direction of the base body;
a water-permeable filter sheet attached to the base body so as to close the upper part of the stretchable slit along the longitudinal direction of the base body at the lower part of the plurality of face plates;
a backup material sandwiched over the entire length of the stretchable slit between the two base bodies;
a water-impermeable elastic sealing material installed over the entire length of the elastic slit on the backup material;
a water collecting space defined by the two base bodies, the filter sheet, and an elastic sealing material;
The plurality of face plates are fixed to one of the base bodies by inserting the stud bolts into the bolt holes of the plurality of face plates and screwing nuts onto the stud bolts,
Bridge expansion device. The bridge expansion and contraction device according to claim 1, wherein the base body has an arrangement groove on its upper surface with a depth corresponding to the thickness of the filter sheet. 3. The bridge expansion and contraction device according to claim 1, wherein said filter sheet has slack toward said water collecting space at the design maximum width of said expansion and contraction slit. 4. The face plate according to any one of claims 1 to 3, wherein the face plate has a two-layer structure of a support plate covering the upper part of the base body and a protection plate covering the surface of the support plate. The bridge expansion and contraction device according to the paragraph. The bridge stretching device according to any one of claims 1 to 4, wherein the filter sheet is made of a water-permeable sheet made of high-strength polyester fiber. 6. According to any one of claims 1 to 5, characterized in that the base web has a plurality of guides extending from the height of the upper edge of the base body in the direction of the bridge girder and/or abutment. A bridge expansion device as described.

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