Expansion device for bridge and construction method thereof

Abstract

To provide an expansion device for a bridge generating excellent strength.SOLUTION: An expansion device 1 for a bridge is provided with a buried space 6 provided in a pair of bridge parts 2, 2 forming a joint gap 3 so as to straddle the joint gap 3, and a cushioning material 4 blocking the joint gap 3. A block body 10a, which is mainly made of an ultra-fast curing resin, formed in a columnar shape in advance so as to have a height h shorter than a depth d of the buried space 6, and which is installed in the bottom center region of the buried space 6 via a first insulating sheet 9a, a second insulating sheet 9b covering an upper surface part of the block body 10a installed in the buried space 6, first filling layers 10b, 10b which are filled in the buried space 6 in which the block body 10a is installed so as to be flush with the upper surface of the block body 10a and then cured, and a second filling layer 10c which is cured after being stacked on the block body 10a and the first filling layer 10b in the buried space 6.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an expansion device for a bridge to be installed in a gap of a bridge, and a construction method thereof. [Background technology]

[0002] As an example of this type of expansion device, one that is known is that disclosed in Patent Document 1, which includes a buried space that is provided across the gap in the portion of a pair of bridges that forms the gap, and a buffer material that closes the gap in an elastically deformable manner. In this device, a buried space is provided across the gap in the portion of a pair of bridges that forms the gap, and a filler is filled into the buried space so that it is flush with the upper surface of the bridge portion, and then the filler is hardened. Then, after the filler is filled into the buried space, the upper surface of the filler is covered with a pavement made of an asphalt mixture.

[0003] Such expansion joints are usually replaced periodically in consideration of deterioration over time, and vehicle traffic must be restricted during the replacement work. Therefore, it is desirable to shorten the time during which vehicles are restricted as much as possible. In such cases, it is possible to use a filler whose main component is an ultra-fast curing resin (such as polyurea resin) in order to shorten the construction time. However, it has been found that filling the buried space with a single layer of filler and curing it does not provide sufficient strength (elongation rate and compression rate). Moreover, the process of covering the top surface of the filler with a pavement body after it has hardened is also an obstacle to shortening the construction time. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 5620687 Summary of the Invention [Problem to be solved by the invention]

[0005] In view of the above, an object of the present invention is to provide an expansion device for a bridge that can generate excellent strength, and a construction method thereof. [Means for solving the problem]

[0006] In order to solve the above problems, the bridge expansion device of the present invention is installed in the gap of a bridge and is characterized in that it further comprises: an embedded space provided in a portion of a pair of bridges that forms a gap so as to span the gap, a buffer material that elastically closes the gap, a block body made of ultra-fast curing resin as a main component, formed in advance into a columnar shape with a height shorter than the depth of the embedded space, and installed in the center region of the bottom surface of the embedded space via a first insulating sheet, a second insulating sheet that covers the upper surface portion of the block body installed in the embedded space, a first filling layer made of ultra-fast curing resin as a main component that is filled in the embedded space in which the block body is installed so as to be flush with the upper surface of the block body and then hardened, and a second filling layer made of ultra-fast curing resin as a main component that is layered on the block body and the first filling layer in the embedded space and then hardened. Note that the "bridge portion" in this invention means the deck slab.

[0007] In order to solve the above problems, a construction method for a bridge expansion device of the present invention is provided to be installed in a gap between bridges, and includes the steps of providing an embedded space across the gap in a portion of a pair of bridges that forms the gap, and providing a buffer material that can elastically deform to fill the gap, and further includes the steps of: preforming a columnar block body whose main component is ultra-fast curing resin and whose height is shorter than the depth of the embedded space; installing the block body in the central region of the bottom surface of the embedded space via a first insulating sheet; filling the embedded space in which the block body is installed with a first filler whose main component is ultra-fast curing resin so as to be flush with the top surface of the block body, and providing a second insulating sheet so as to cover the top surface of the block body; and layering a second filler whose main component is ultra-fast curing resin on the block body and the first filler in the embedded space.

[0008] In the present invention, the first filling layer is mainly composed of the same ultrafast curing resin as the block body, and the first filling layer and the second filling layer are of the same composition, and it is preferable that the first filling material is mainly composed of the same ultrafast curing resin as the block body, and the first filling material and the second filling material are of the same composition. In addition, the "ultrafast curing resin" of the present invention means a resin (e.g., polyurea resin, polyurethane resin, epoxy resin, cationic acrylic resin, mortar, etc.) that cures in a short time (e.g., 4 to 5 hours) at room temperature after mixing the base agent and the curing agent.

[0009] Here, as a result of intensive research by the present inventors, the following has been discovered. That is, it has been discovered that the elongation rate and compression rate of a filler mainly composed of ultra-fast curing resin, which is laminated in a plurality of layers in the embedding space and cured, is dramatically improved compared to the above-mentioned conventional example (in other words, the filler is filled in the embedding space in a single layer and cured). Based on this discovery, in the present invention, in consideration of the construction of the expansion device in a short time, a columnar block body mainly composed of ultra-fast curing resin is prepared, which is installed in the center area of ​​the bottom surface of the embedding space via a first insulating sheet, and the first filler is filled in the embedding space so as to be flush with the upper surface of the block body to form a first filling layer. Then, the upper surface portion of the block body is covered with a second insulating sheet, and the second filler is laminated to form a second filling layer. As a result, it is possible to obtain an expansion device having a dramatically higher elongation rate and compression rate than the above-mentioned conventional example. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a cross-sectional view for explaining a bridge expansion device according to an embodiment of the present invention. [Diagram 2] 2A to 2C are diagrams for explaining a construction method of an expansion device for a bridge according to the present embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, with reference to the drawings, an expansion device 1 for a bridge according to an embodiment of the present invention will be described, in which a pair of bridge parts are deck slabs arranged side by side with a pavement laid on their upper surfaces (hereinafter, simply referred to as "expansion device 1"). With reference to FIG. 1, in the expansion device 1, a gap 3 is formed between deck slabs 2, 2 arranged side by side, and a buffer material 4 is provided to cover the gap 3 in an elastically deformable manner. The material, shape, etc. of the buffer material 4 are appropriately selected according to the width of the gap 3. As the buffer material 4, for example, a cylindrical or angular backup material made of polyurethane resin can be used.

[0012] A pavement 5 having a base layer 5a and a surface layer 5b is laid on the upper surface of each of the decks 2, 2. A buried space 6 is formed in the decks 2, 2 and the pavements 5, 5 so as to straddle the gap 3. As the pavement 5 can be made of a known asphalt mixture or concrete, further explanation is omitted. In the following, the juxtaposition direction of the decks 2, 2 arranged side by side with the gap 3 between them (the left-right direction in FIG. 1) is defined as the X-axis direction, and the road width direction of the decks 2, 2 perpendicular to the X-axis direction (the direction perpendicular to the paper surface in FIG. 1) is defined as the Y-axis direction.

[0013] The buried space 6 has a predetermined depth d (for example, 12 cm) from the upper surface of the pavement 5, and has a rectangular cross-sectional shape defined by side walls extending in the X-axis direction and the Y-axis direction. A gap plate 7 is laid on the bottom surface of the buried space 6 so as to straddle the gap 3. The gap plate 7 is fixed to one of the floor slabs 2 by a plurality of anchor bolts 8 provided at predetermined intervals in the Y-axis direction. Although not specifically illustrated or described, a waterproof sheet is provided between the gap plate 7 and the bottom surface of the buried space 6 to prevent water leakage downward from the buffer material 4 and the buffer material 4 from falling, and the end of the waterproof sheet in the X-axis direction is fixed to one of the floor slabs 2 by each anchor bolt 8. Since the gap plate 7, the anchor bolts 8, and the waterproof sheet can be publicly known ones, further description will be omitted.

[0014] In the embedding space 6, there are provided a block body 10a installed via a first insulating sheet 9a in the central region in the X-axis direction of the bottom surface of the embedding space 6, first filling layers 10b, 10b having the same thickness as the block body 10a, and a second filling layer 10c laminated on the block body 10a and the first filling layer 10b, 10b. In addition, a second insulating sheet 9b is provided between the block body 10a and the second filling layer 10c so as to cover the upper surface portion of the block body 10a. The first and second insulating sheets 9a, 9b can be made of commercially available asphalt felt, so a detailed description will be omitted.

[0015] The block body 10a is made mainly of ultrafast curing resin, which will be described later, and is molded in advance into a rectangular parallelepiped shape having a height h (for example, 4 cm to 6 cm) shorter than the depth d of the embedding space 6. The first filling layers 10b, 10b are formed by filling and curing the first filling material, which will be described later, between each side of the block body 10a and each side of the embedding space 6, and the upper surface of the first filling layers 10b, 10b is flush with the upper surface of the block body 10a. The second filling layer 10c is formed by layering the second filling material, which will be described later, on the block body 10a and the first filling layers 10b, 10b with a predetermined thickness t (for example, 4 cm to 6 cm) and curing it. The upper surface of the second filling layer 10c is coated with a coating material 11 to prevent the filling material from peeling off, so that the coating material is flush with the upper surface of the pavement 5. The coating material 11 can be a mixture of ultrafast curing resin and abrasive material.

[0016] In this embodiment, the filler forming the block body 10a, and the first and second fillers forming the first and second filling layers 10b and 10c are all the same component, and a mixture of the main component ultrafast curing resin and aggregate can be used. As the ultrafast curing resin, for example, polyurea resin, polyurethane resin, epoxy resin, cationic acrylic resin, mortar, etc. can be used, and the volume ratio of the ultrafast curing resin to the total volume of each filler is set in the range of 40% to 50%. As the aggregate, a material containing crushed stone and sand can be used. As the crushed stone, for example, a mixture of crushed stone No. 6 (5 to 13 mm) and crushed stone No. 7 (2.5 to 5 mm) can be used. As the sand, a mixture of coarse sand (0.075 to 3 mm) and fine sand (0.02 to 0.2 mm) can be used. In addition to the ultrafast curing resin and aggregate, each filler may contain vinylon fiber, etc. Hereinafter, a method for constructing the expansion device 1 of this embodiment will be described taking as an example a case in which the filler forming the block body 10a, the first and second filler materials, have the same components.

[0017] First, each of the deck slabs 2,2 and the pavement 5 (base layer 5a and surface layer 5b) laid on the top surface of each deck slab 2 are excavated, and an embedded space 6 is provided across the gap 3, as shown in Fig. 2(a). Next, a buffer material 4 is provided in the gap 3, and a waterproof sheet (not shown) and a gap plate 7 are laid on the bottom of the embedded space 6. The waterproof sheet and gap plate 7 are fixed to one of the deck slabs 2 with anchor bolts 8 (see Fig. 2(b)).

[0018] Then, as shown in Fig. 2(c), a block body 10a, which has been formed into a rectangular parallelepiped shape by hardening the filler in advance, is placed in the center region of the bottom surface of the embedding space 6 via a first insulating sheet 9a. After that, the first filler is filled between each side surface of the block body 10a and each side surface of the embedding space 6 so as to be flush with the upper surface of the block body 10a, thereby forming first filling layers 10b, 10b. At this time, a second insulating sheet 9b is placed so as to cover the upper surface portion of the block body 10a (see Fig. 2(d)).

[0019] After the filled first filling material is cured, the second filling material is laminated on the block body 10a and the first filling layers 10b, 10b to a predetermined thickness to form the second filling layer 10c (see FIG. 2(e)). After the laminated second filling material is cured, the upper surface of the second filling layer 10c is covered with a coating material 11 (see FIG. 2(f)).

[0020] According to the above, in consideration of the construction of the expansion device 1 in a short time, a rectangular parallelepiped block body 10a mainly composed of an ultrafast curing resin is molded, and this is installed in the center area of ​​the bottom surface of the embedding space 6 via a first insulating sheet 9a, and then the embedding space 6 is filled with a first filling material so as to be flush with the upper surface of the block body 10a to form a first filling layer 10b, 10b. Then, the upper surface portion of the block body 10a is covered with a second insulating sheet 9b, and then a second filling material is laminated to form a second filling layer 10c. This makes it possible to obtain an expansion device 1 with a dramatically higher elongation rate and compression rate than the conventional example.

[0021] Next, in order to confirm the above-mentioned effect, the following experiment was carried out. First, the filler forming the block body 10a, the first and second fillers were assumed to have the same components, and a filler mainly made of polyurea resin as an ultra-fast curing resin was prepared. That is, aggregate was kneaded with a commercially available polyurea resin base material using a kneading mixer. As the aggregate, a mixture of crushed stone No. 6 (5-13 mm), crushed stone No. 7 (2.5-5 mm), and coarse sand (0.075-3 mm) was used in advance, and commercially available vinylon fiber was further added at a weight ratio of 2% to the polyurea resin and kneaded. An appropriate amount of a curing agent for the polyurea resin was mixed into this mixture so that the volume ratio of the polyurea resin to the volume of the polyurea resin (base material and curing agent) and the aggregate was 40%.

[0022] Next, a rectangular parallelepiped block 10a (width 20 cm, length 15 cm, height 6 cm) was molded using the above-mentioned filler, and the block 10a was provided with commercially available asphalt felt insulating sheets 9a, 9b on the top and bottom surfaces and placed in the center of the bottom width direction in a steel formwork (width 40 cm, length 15 cm, height 12 cm). The filler was then filled into the space between the side wall of the formwork and the block 10a to the same thickness as the height of the block 10a, to obtain a first filling layer 10b, 10b. Thereafter, the filler was layered on the block 10a and the first filling layer 10b, 10b up to the top end of the formwork (i.e., about 6 cm thick), and a predetermined time (about 2 hours) was allowed to pass, and the second filling layer 10c hardened, and then the block was demolded to obtain the invention.

[0023] A tensile test was conducted on the product of the invention obtained in this way, and it was confirmed that the product had sufficient elasticity and did not break or crack up to an elongation rate of 10%. In addition, a compression test was conducted on the product of the invention, and it was confirmed that the amount of settlement of the product was the same as that of the compression test specimen made of asphalt (1mm or less), and that the compressive strength was sufficient to ensure that the vehicle could travel without any problems even if the wheel load of the vehicle was applied.

[0024] Although the embodiment of the present invention has been described above, various modifications are possible without departing from the scope of the technical concept of the present invention. In the above embodiment, the pavement 5 is laid on the upper surface of the deck 2, 2, but the present invention can also be applied to a deck on which no pavement is laid. In the above embodiment, the filler forming the block body 10a, the first and second fillers are the same composition, but each filler may be a different composition. In the above embodiment, the polyurethane resin is used as the ultra-fast curing resin, but the present invention can also be applied to cases where polyurethane resin, epoxy resin, cationic acrylic resin, mortar, etc. are used. [Explanation of symbols]

[0025] d...depth of buried space, h1...height of block body, 1...expansion device, 2...deck slab (bridge part), 3...gap, 4...buffer material, 5...pavement (bridge part), 6...buried space, 9a, 9b...insulating sheet, 10a...block body, 10b...first filling layer, 10c...second filling layer.

Claims

1. A bridge expansion device installed in the gap of a bridge, A bridge structure having a buried space provided across a gap between a pair of bridge beams, and a cushioning material that can elastically deform to close the gap, a block body made mainly of ultrafast curing resin, formed in advance into a columnar shape having a height shorter than the depth of the embedding space, and installed in a bottom central region of the embedding space via a first insulating sheet; a second insulating sheet covering an upper surface portion of the block body installed in the buried space; a first filling layer mainly composed of an ultrafast curing resin, which is filled into the embedding space in which the block body is placed so as to be flush with the upper surface of the block body and then cured; A bridge expansion device further comprising a second filling layer mainly composed of an ultra-fast curing resin which is stacked on the block body and the first filling layer in the embedded space and then cured.

2. 2. The bridge expansion device according to claim 1, characterized in that the first filling layer is mainly composed of the same ultra-fast curing resin as the block body, and the first filling layer and the second filling layer are composed of the same material.

3. A construction method for a bridge expansion device to be installed in a gap of a bridge, comprising the steps of: A method including a step of providing a buried space across a gap between a pair of bridges and providing a buffer material that can elastically deform to close the gap, A step of molding a columnar block body in advance, the columnar block body being made mainly of an ultrafast curing resin and having a height shorter than the depth of the embedding space; a step of placing the block body in a bottom central region of the embedding space via a first insulating sheet; a step of filling a first filler containing an ultrafast curing resin as a main component into the embedding space in which the block body is placed so as to be flush with an upper surface of the block body, and providing a second insulating sheet so as to cover the upper surface of the block body; and laminating a second filler material mainly composed of an ultrafast curing resin on the block body and the first filler material in the buried space.

4. 4. The construction method for a bridge expansion device according to claim 3, wherein the first filler is mainly composed of the same ultra-fast curing resin as the block body, and the first filler and the second filler have the same components.

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