Bridge slab joining structure and manufacturing method of bridge slab joining structure
The described slab joint structure effectively reinforces loop reinforcing bars in precast slabs by aligning loop reinforcements perpendicularly and using external reinforcing bars covered by concrete, addressing inefficiencies in existing joint structures.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- MM BRIDGE CO LTD
- Filing Date
- 2024-12-25
- Publication Date
- 2026-07-07
Smart Images
Figure 2026112913000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a floor slab joint structure and a method for manufacturing the floor slab joint structure.
Background Art
[0002] A floor slab joint structure for joining a plurality of precast floor slabs is known (for example, see Patent Document 1).
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] In the floor slab joint structure described in Patent Document 1, loop reinforcing bars protruding from the side surfaces of opposing precast floor slabs are arranged so as to overlap each other, and a concrete portion is formed by special concrete without inserting reinforcing bars in the loop in a direction perpendicular to the bridge axis. In the floor slab joint structure as described above, it is required to arrange the reinforcing bars so as to appropriately reinforce the loop reinforcing bars. I
[0005] [[ID=ID=38]] The present invention has been made in view of the above, and an object thereof is to provide a floor slab joint structure and a method for manufacturing the floor slab joint structure capable of arranging reinforcing bars so as to appropriately reinforce loop reinforcing bars.
Means for Solving the Problems
[0006] The slab joint structure according to the present invention comprises two precast slabs, each having a plurality of loop reinforcements protruding in a first direction and aligned in a second direction perpendicular to the first direction, and joined in such a state that the loop portions of each loop reinforcement overlap in the first direction; reinforcement bars arranged along the loop portions at the joint portion of the two precast slabs, on the outside in both directions of the first direction relative to the loop portions, so as to penetrate the plurality of loop reinforcements in the second direction; and a concrete portion arranged at the joint portion so as to cover the loop reinforcements and the reinforcement bars.
[0007] A method for manufacturing a slab joint structure according to the present invention includes a precast slab arrangement step of arranging two precast slabs such that the loops face each other, each having a plurality of loop bars that protrude in a first direction and are aligned in a second direction perpendicular to the first direction, and each having reinforcing bars arranged inside the plurality of loop bars so as to penetrate the plurality of loop bars in the second direction; a positioning step of arranging the two precast slabs such that the loop portions of each loop bar overlap in the first direction and the reinforcing bars are arranged on the outside of the loop portions in both directions of the first direction; a reinforcing bar arrangement step of arranging the reinforcing bars at predetermined positions along the loop bars; and a concrete arrangement step of arranging a concrete portion so as to cover the loop bars and the reinforcing bars. [Effects of the Invention]
[0008] According to the present invention, it is possible to provide a slab joint structure and a method for manufacturing a slab joint structure that allows for the arrangement of reinforcing bars to appropriately reinforce loop reinforcing bars. [Brief explanation of the drawing]
[0009] [Figure 1] Figure 1 is a schematic diagram showing an example of a slab joint structure according to the embodiment. [Figure 2] Figure 2 is a schematic diagram showing an example of a slab joint structure according to the embodiment. [Figure 3] Figure 3 is a schematic diagram showing an example of a slab joint structure according to the embodiment. [Figure 4] Figure 4 is a flowchart showing an example of a method for manufacturing a slab joint structure according to the embodiment. [Figure 5] Figure 5 shows an example of the precast floor slab placement process. [Figure 6] Figure 6 shows an example of the positioning process. [Figure 7] Figure 7 shows an example of the rebar placement process. [Figure 8] Figure 8 shows an example of the concrete placement process. [Figure 9] Figure 9 is a schematic diagram showing another example of the slab joint structure according to the embodiment. [Modes for carrying out the invention]
[0010] Hereinafter, embodiments of the deck slab joint structure and the method for manufacturing the deck slab joint structure according to the present invention will be described with reference to the drawings. However, the present invention is not limited by these embodiments. Furthermore, the components in the following embodiments include those that are easily substituted or substantially identical to those that are easily substituted by those skilled in the art.
[0011] Figures 1 to 3 schematically show an example of a slab joint structure according to this embodiment. Figure 1 is a plan view, and Figure 2 is a side view. Figure 3 is an enlarged view of the joint portion in Figure 2. The slab joint structure 100 shown in Figures 1 to 3 can be applied, for example, as a structure for joining multiple precast slabs installed on a main girder. In this embodiment, two precast slabs PC adjacent to each other in the joining direction (hereinafter referred to as the first direction D1) are described as the first precast slab 10 and the second precast slab 20.
[0012] As shown in Figure 1, the slab joint structure 100 comprises a first precast slab 10, a second precast slab 20, reinforcing bars 30, and a concrete section 40. The slab joint structure 100 joins the first precast slab 10 and the second precast slab 20 at a joint section 50. In the following description, the first direction D1 is the direction along the horizontal plane. In the following description, when describing the direction of the slab joint structure 100, in addition to the first direction D1, the direction along the horizontal plane and perpendicular to the first direction D1 is referred to as the second direction D2, and the direction perpendicular to the first direction D1 and the second direction D2 (up and down direction, vertical direction) is referred to as the third direction D3.
[0013] The first precast slab 10 has a main body 11 and a plurality of loop reinforcement bars 12. The main body 11 is formed in a plate-like or block-like shape using, for example, concrete. The plurality of loop reinforcement bars 12 are arranged on the side surface 11a of the main body 11. The plurality of loop reinforcement bars 12 protrude from the side surface 11a in a first direction D1. In other words, the loop reinforcement bars 12 protrude toward the side surface 21a of the second precast slab 20, which will be described later.
[0014] Each loop reinforcement bar 12 has a straight section 12a and a loop section 12b. Two straight sections 12a are arranged on the side surface 11a of each loop reinforcement bar 12, spaced apart in the vertical direction (third direction D3). The straight sections 12a are embedded in the main body 11 of the first precast floor slab 10, with a portion extending outwards from the side surface 11a along the first direction D1. The loop sections 12b connect the ends of the straight sections 12a in the direction of protrusion. The loop sections 12b have a curved shape that is convex in the direction of protrusion of the loop reinforcement bar 12.
[0015] The second precast slab 20 has a main body 21 and a plurality of loop reinforcement bars 22. The main body 21 is formed in a plate-like or block-like shape using, for example, concrete. The plurality of loop reinforcement bars 22 are arranged on the side surface 21a of the main body 21. The side surface 21a faces the side surface 11a of the main body 11 of the first precast slab 10. The plurality of loop reinforcement bars 22 protrude from the side surface 21a in a first direction D1. In other words, the loop reinforcement bars 22 protrude toward the side surface 11a of the first precast slab 10.
[0016] Each loop bar 22 has a straight portion 22a and a loop portion 22b. Two straight portions 22a are arranged at intervals in the vertical direction (the third direction D3) on the side surface 21a for each loop bar 22. The straight portion 22a is embedded in the main body portion 21 of the second precast floor slab 20 and extends so that a part thereof protrudes from the side surface 21a along the first direction D1. The loop portion 22b connects the tips of the straight portions 22a in the protruding direction. The loop portion 22b has a curved shape that bulges in the protruding direction of the loop bar 22.
[0017] The first precast floor slab 10 and the second precast floor slab 20 are arranged such that the loop bars 12 and the loop bars 22 are alternately arranged in the second direction D2, and the loop portion 12b of the loop bar 12 and the loop portion 22b of the loop bar 22 overlap when viewed from the second direction D2. With this arrangement, a circular or oval wrap portion 60 (see FIG. 3) surrounded by the loop portion 12b and the loop portion 22b is formed when viewed from the second direction D2.
[0018] The reinforcing bar 30 is formed in a linearly extending state. The reinforcing bar 30 is arranged inside the loop bar 12 and the loop bar 22, respectively, at the joint portion 50 between the first precast floor slab 10 and the second precast floor slab 20. The reinforcing bar 30 is arranged outside both directions of the first direction D1 with respect to the wrap portion 60 at the joint portion 50. The reinforcing bar 30 is arranged along the second direction D2 and is arranged so as to penetrate a plurality of loop bars 12 and 22. In the present embodiment, the reinforcing bar 30 is provided in a state where it is not arranged inside the wrap portion 60.
[0019] A plurality of reinforcing bars 30 are arranged on the first precast floor slab 10 side of the wrap portion 60 and on the second precast floor slab 20 side of the wrap portion 60, respectively. In the present embodiment, the reinforcing bar 30 is arranged so as to contact the upper and lower straight portions 12a of the loop bar 12 on the first precast floor slab 10 side of the wrap portion 60. Further, the reinforcing bar 30 is arranged so as to contact the upper and lower straight portions 22a of the loop bar 22 on the second precast floor slab 20 side of the wrap portion 60.
[0020] In this embodiment, separate from the reinforcing bars 30, reinforcing bars (outer reinforcing bars) 35 are provided on the outside of the loop bars 12 and 22. The reinforcing bars 35 extend in the second direction D2 and are arranged to straddle multiple loop bars 12 and 22. The reinforcing bars 35 are positioned at a location that is in contact with the upper part of the upper straight sections 12a and 22a of the loop bars 12 and 22, and at a location that is in contact with the lower part of the lower straight sections 12a and 22a of the loop bars 12 and 22, respectively.
[0021] The concrete section 40 is positioned to cover the loop reinforcement bars 12 and 22 and the reinforcing bars 30 and 35 at the joint 50 between the first precast floor slab 10 and the second precast floor slab 20.
[0022] Next, a method for manufacturing the slab joint structure 100 configured as described above will be explained. Figure 4 is a flowchart showing an example of a method for manufacturing the slab joint structure 100 according to this embodiment. As shown in Figure 4, the method for manufacturing the slab joint structure 100 according to this embodiment includes a precast slab placement step S10, a positioning step S20, a reinforcement bar placement step S30, and a concrete placement step S40.
[0023] The precast slab placement process S10 involves arranging two precast slab PCs such that the loop bars 12 and 22 face each other: a first precast slab 10 having a plurality of loop bars 12 protruding in a first direction D1 and aligned in a second direction D2, and a second precast slab 20 having a plurality of loop bars 22 protruding in a first direction D1 and aligned in a second direction D2, and a second precast slab 20 having a plurality of loop bars 30 positioned inside the plurality of loop bars 22, and a second precast slab PC facing each other.
[0024] Figure 5 shows an example of the precast floor slab placement process. As shown in Figure 5, in the precast floor slab placement process S10, reinforcing bars 30 are pre-placed inside the multiple loop reinforcements 12 of the first precast floor slab 10 and inside the multiple loop reinforcements 22 of the second precast floor slab 20. The reinforcing bars 30 may be temporarily fixed in predetermined positions inside the multiple loop reinforcements 12 and 22. By pre-placing the reinforcing bars 30 inside the multiple loop reinforcements 12 and 22 in this way, the effort of placing the reinforcing bars 30 inside the multiple loop reinforcements 12 and 22 at the work site can be saved.
[0025] After performing the precast slab placement process S10 as described above, the positioning process S20 is performed. In the positioning process S20, the first precast slab 10 and the second precast slab 20 are positioned such that the loop portions of the respective loop reinforcements 12 and 22 overlap in the first direction D1 to form an overlap portion 60, and the reinforcement bars 30 are positioned on the outside of the overlap portion 60 in both directions of the first direction D1.
[0026] Figure 6 shows an example of the positioning process. As shown in Figure 6, in the positioning process S20, positioning can be performed by moving one of the first precast floor slab 10 and the second precast floor slab 20 toward the other side. In the example shown in Figure 6, the first precast floor slab 10 is not moved, and the second precast floor slab 20 is moved toward the first precast floor slab 10, but the method is not limited to this example. The second precast floor slab 20 may not be moved, and the first precast floor slab 10 may be moved toward the second precast floor slab 20. Alternatively, both the first precast floor slab 10 and the second precast floor slab 20 may be moved toward each other.
[0027] By performing the positioning process S20, in a side view (see Figure 6), the reinforcing bars 30 inside the loop reinforcement bars 12 of the first precast slab 10 will be positioned in the area enclosed by the side surface 11a of the main body 11, the upper and lower straight sections 12a of the loop reinforcement bars 12, and the loop section 22b of the loop reinforcement bars 22 on the second precast slab 20 side of the lap section 60. Similarly, in a side view (see Figure 6), the reinforcing bars 30 inside the loop reinforcement bars 22 of the second precast slab 20 will be positioned in the area enclosed by the side surface 21a of the main body 21, the upper and lower straight sections 22a of the loop reinforcement bars 22, and the loop section 12b of the loop reinforcement bars 12 on the first precast slab 10 side of the lap section 60.
[0028] After performing the positioning process S20 as described above, the rebar placement process S30 is performed. In the rebar placement process S30, the reinforcing bars 30 are placed in predetermined positions along the loop reinforcements 12 and 22.
[0029] Figure 7 shows an example of the rebar placement process S30. As shown in Figure 7, in the rebar placement process S30, rebars 30 are placed at predetermined positions along the loop bars 12 and 22. In this embodiment, rebars 30 are placed and temporarily fixed at positions touching the lower part of the upper straight section 12a of loop bar 12, the upper part of the lower straight section 12a of loop bar 12, the lower part of the upper straight section 22a of loop bar 22, and the upper part of the lower straight section 22a of loop bar 22. Note that rebars 30 may also be placed so as to be in contact with the loop sections 12b and 22b of loop bars 12 and 22.
[0030] Furthermore, as shown in Figure 7, in the rebar placement process S30, rebars 35, which are outer rebars different from rebars 30, are placed on the outside of loop rebars 12 and 22 along the second direction D2. In this embodiment, the rebars are placed at positions that are in contact with the upper part of the upper straight sections 12a and 22a of loop rebars 12 and 22, and at positions that are in contact with the lower part of the lower straight sections 12a and 22a of loop rebars 12 and 22, respectively, and then temporarily fixed.
[0031] After performing the rebar placement process S30 as described above, the concrete placement process S40 is performed. In the concrete placement process S40, the concrete section 40 is placed so as to cover the loop reinforcement bars 12 and 22 and the rebars 30 and 35. Figure 8 shows an example of the concrete placement process S40. As shown in Figure 8, in the concrete placement process S40, the concrete section 40 can be formed using concrete equivalent to that used for the main deck slab 10, for example, without using any special concrete.
[0032] As described above, the slab joint structure 100 according to this embodiment comprises two precast slabs PC (first precast slab 10 and second precast slab 20) which are joined together with each having a plurality of loop reinforcements 12, 22 that protrude in a first direction D1 and are aligned in a second direction D2 perpendicular to the first direction D1, and the loop portions 12b, 22b of each loop reinforcement 12, 22 overlapping in the first direction D1; and in the joint portion 50 of the two precast slabs PC, reinforcing bars 30 are arranged along the loop portions 12b, 22b so as to penetrate the plurality of loop reinforcements 12, 22 in the second direction D2, on the outside in both directions of the first direction D1 relative to the loop portions 12b, 22b, and a concrete portion 40 is arranged in the joint portion 50 so as to cover the loop reinforcements 12, 22 and the reinforcing bars 30.
[0033] With this configuration, at the joint portion 50 of the two precast floor slabs PC, the reinforcing bars 30 are arranged along the loop portions 12b and 22b so as to penetrate multiple loop bars 12 and 22 in the second direction D2 on the outside in both directions of the first direction D1 relative to the loop portions 12b and 22b, thereby appropriately reinforcing the loop portions 12b and 22b of the loop bars 12 and 22.
[0034] In the slab joint structure 100 according to this embodiment, the concrete portion 40 is placed in the joint portion 50 in a manner in which the reinforcing bars 30 are not placed inside the overlap portion 60.
[0035] With this configuration, the reinforcing bars 30 are not placed inside the overlapping section 60, allowing for efficient placement of the reinforcing bars 30.
[0036] In the slab joint structure 100 according to this embodiment, a reinforcing bar 35 is further provided, which is arranged separately from the reinforcing bars 30 on the outside of the loop reinforcements 12 and 22 along the second direction D2.
[0037] With this configuration, the strength of the joint 50 can be ensured by arranging the reinforcing bars 35 separately from the reinforcing bars 30.
[0038] The manufacturing method of the slab joint structure 100 according to this embodiment is a precast slab arrangement step S1 in which two precast slabs PC (first precast slab 10 and second precast slab 20) are arranged so that the loop reinforcements 12 and 22 face each other, each having a plurality of loop reinforcements 12 and 22 that protrude in a first direction D1 and are aligned in a second direction D2 perpendicular to the first direction D1, and a reinforcement bar 30 that is arranged inside the plurality of loop reinforcements 12 and 22 so as to penetrate the plurality of loop reinforcements 12 and 22 in the second direction D2, The process includes: positioning step S20 for positioning two precast floor slabs PC such that the loop portions 12b and 22b of the respective loop reinforcements 12 and 22 overlap in the first direction D1 to form an overlap portion 60, and the reinforcing bars 30 are positioned on the outside of the overlap portion 60 in both directions of the first direction D1; reinforcing bar placement step S30 for positioning the reinforcing bars 30 at predetermined positions along the loop reinforcements 12 and 22; and concrete placement step S40 for positioning the concrete portion 40 so as to cover the loop reinforcements 12 and 22 and the reinforcing bars 30.
[0039] With this configuration, by pre-positioning the reinforcing bars 30 inside each of the multiple loop bars 12 and 22, the effort required to position the reinforcing bars 30 inside each of the loop bars 12 and 22 at the construction site can be eliminated. This reduces the effort required during construction while appropriately reinforcing the loop portions 12b and 22b of the loop bars 12 and 22.
[0040] In the manufacturing method of the slab joint structure 100 according to this embodiment, in the reinforcement bar arrangement step S30, a reinforcement bar 35 different from the reinforcement bar 30 is arranged on the outside of the loop reinforcement bars 12 and 22 along the second direction D2.
[0041] With this configuration, the strength of the joint 50 can be ensured by arranging the reinforcing bars 35 separately from the reinforcing bars 30.
[0042] The technical scope of the present invention is not limited to the embodiments described above, and modifications can be made as appropriate without departing from the spirit of the invention. For example, in the above embodiments, as an example of a configuration in which the concrete portion 40 is arranged in a state in which the reinforcing bars 30 are not arranged inside the overlap portion 60 at the joint portion 50, a configuration in which the concrete portion 40 is arranged over the entire inside of the overlap portion 60 was described, but the invention is not limited to this configuration.
[0043] Figure 9 is a schematic diagram showing another example of a slab joint structure according to the embodiment. In the slab joint structure 100A shown in Figure 9, the joint portion 50A is configured such that a joint 70 is placed inside at least one (two in Figure 9) overlapping portion 60. Thus, as an example of a state in which no reinforcing bars 30 are placed inside the overlapping portion 60 of the joint portion 50A, the concrete portion 40 may be configured with other members such as joints 70, which are different from the reinforcing bars 30, placed inside the overlapping portion 60. Note that in the joint portion 50A shown in Figure 9, a configuration without reinforcing bars 35 is shown as an example, but reinforcing bars 35 may be provided. [Explanation of Symbols]
[0044] 10. First precast floor slab 11,21 Main body 11a,21a side 12,22 Loop muscle 12a,22a Straight section 12b, 22b Loop section 20. Second precast floor slab 30,35 Reinforcement bars 40 Concrete section 50 Joint part 60 Wrap section 70 Joint 100 Floor slab joint structure D1 1st direction D2 2nd direction D3 Third direction S10 Precast floor slab placement process S20 Positioning process S30 Reinforcement bar placement process S40 Concrete Placement Process PC precast slab
Claims
1. Two precast floor slabs are joined together, each having a plurality of loop reinforcements that protrude in a first direction and are aligned in a second direction perpendicular to the first direction, and the loop portions of each of the loop reinforcements are arranged to overlap in the first direction to form an overlapping portion. In the joint portion of the two precast floor slabs, a reinforcing bar is arranged along the loop portion so as to penetrate the loop reinforcement in the second direction, on the outside in both directions of the first direction relative to the overlapping portion, A concrete portion is arranged at the joint so as to cover the loop reinforcement and the reinforcement. A slab joint structure equipped with a floor slab.
2. In the aforementioned joint portion, the concrete portion is positioned such that the reinforcing bars are not placed inside the overlapping portion. The slab joining structure according to claim 1.
3. The loop reinforcement further comprises an outer reinforcement bar, which is arranged separately from the aforementioned reinforcement bar and positioned on the outside of the loop reinforcement bar along the second direction. The slab joining structure according to claim 1.
4. A precast floor slab arrangement step, in which two precast floor slabs are arranged such that the loop reinforcements face each other, each having a plurality of loop reinforcements that protrude in a first direction and are aligned in a second direction perpendicular to the first direction, and each having reinforcements arranged inside the plurality of loop reinforcements so as to penetrate the plurality of loop reinforcements in the second direction, A positioning step of positioning the two precast floor slabs such that the loop portions of each of the aforementioned loop reinforcements overlap in the first direction to form an overlap portion, and the reinforcements are positioned on the outside in both directions of the first direction relative to the overlap portion, A rebar placement step involves arranging the reinforcing bars at predetermined positions along the loop reinforcement, A concrete arrangement step involves arranging the concrete portion so as to cover the loop reinforcement and the reinforcement. A method for manufacturing a slab joint structure including a slab joint structure.
5. In the aforementioned reinforcement arrangement step, outer reinforcement bars different from the aforementioned reinforcement bars are arranged on the outside of the loop reinforcement bars along the second direction. A method for manufacturing a slab joint structure according to claim 4.