Synthesizing structure of main girder and concrete floor slab, and re-synthesized method of main girder and concrete floor slab

Abstract

To efficiently re-synthesize a cut and separated concrete floor slab and a main girder.SOLUTION: A synthesized structure of a main girder and a concrete floor slab, in which the concrete floor slab of a bridge separated from the main girder by cutting a joint part is re-synthesized with the main girder, comprises a post-installed anchor disposed in a hanging manner at a predetermined distance from the joint part on each of both sides sandwiching the main girder on a lower surface of the concrete floor slab, a fastening material disposed in the hanging shape on each of both sides across the web on the upper flange lower surface of the main girder, and a synthetic jig disposed on each of both sides across the main girder and connecting the fastening material and the post-installed anchor. The synthetic jig includes a main girder abutting member having one end side of the upper surface connected to the post-installed anchor and the other end side connected to the fastening material.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a composite structure of a bridge in which a concrete floor slab and a steel main girder are integrated, and a method for recombining the concrete floor slab separated from the main girder by cutting a joint portion with the main girder, and a method for recombining the main girder and the concrete floor slab.

Background Art

[0002] In order to perform renewal work of replacing an existing concrete floor slab installed on a main girder of a bridge with a new concrete floor slab, first, a separation work between the existing concrete floor slab and the main girder is performed, and the existing concrete floor slab is cut into a shape that can be loaded on a transport vehicle. After that, the existing concrete floor slab cut into a shape that can be loaded on the transport vehicle is removed. Next, a grounding process of removing concrete scraps, anchor bars, rust, etc. remaining on the upper surface of the main girder is performed. After these operations are completed, an operation of installing a new concrete floor slab on the grounded upper surface of the main girder is performed.

[0003] All of the above operations need to be carried out after implementing construction traffic regulations such as stopping the passage of general vehicles and various passage restrictions. Among them, the existing concrete floor slab is firmly joined to the stud dimple provided on the upper surface of the main girder through concrete. Therefore, the work of separating and removing the existing concrete floor slab and the main girder requires a particularly large amount of labor and time.

[0004] However, in heavy traffic roads in urban areas or mountainous areas sandwiched between long tunnels, implementing construction traffic regulations for a long period of time may have an adverse impact on the traffic environment in the surrounding areas. For this reason, a method that can reduce the labor involved in these operations, shorten the period of implementing construction traffic regulations, and quickly implement renewal work is desired. Under such circumstances, for example, Patent Document 1 discloses a method of performing an operation of cutting a joint portion between an existing concrete floor slab and a main girder, and providing a composite structure for joining the existing concrete floor slab separated by the cutting and the main girder behind it.

[0005] In this way, the existing concrete floor slab of the main girder can be recombined, enabling the bridge to function as a composite girder bridge. Therefore, during the period from the operation of separating the existing concrete floor slab from the main girder to the start of the operation of removing the existing concrete floor slab, it is possible to secure the traffic opening period for general vehicles without imposing restrictions on the running load or regulations on the traffic lane.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] The composite structure of Patent Document 1 utilizes the cut surface formed by cutting the joint between the existing concrete floor slab and the main girder to install the composite jig. In a structure that utilizes such a cut surface, plastering the cut surface, etc. is required as preparatory work.

[0008] In addition, when the width shape (length in the direction perpendicular to the bridge axis) of the joint is small and the composite jig cannot be installed, additional work is required to increase the width by ramming non-shrinking mortar, etc. to secure the installation space for the composite jig. As described above, the installation of the composite jig requires many work steps and is laborious. Furthermore, it has various problems such as low horizontal shear strength, an increase in the installation quantity depending on the site conditions, and on the other hand, the overall shape of the composite jig is large, imposing a heavy burden on the workers during the installation work.

[0009] The present invention has been made in view of such problems, and its main object is to efficiently recombine the cut and separated concrete floor slab and the main girder.

Means for Solving the Problems

[0010] In order to achieve the above object, the composite structure of the main girder and the concrete floor slab of the present invention is a composite structure of the main girder and the concrete floor slab of the bridge separated from the main girder by cutting the joint and then recombining the concrete floor slab of the bridge onto the main girder. On each side of the lower surface of the concrete floor slab sandwiching the main girder, a post-construction anchor is arranged in a hanging manner after providing a predetermined distance from the joint, and on each side of the lower surface of the upper flange of the main girder sandwiching the web, a fastening member is arranged in a hanging manner. Composite jigs are respectively arranged on both sides sandwiching the main girder to connect the fastening member and the post-construction anchor. The composite jig includes a main girder abutting member on the upper surface, one end side of which is connected to the post-construction anchor and the other end side of which is connected to the fastening member.

[0011] The composite structure of the main girder and the concrete floor slab of the present invention is characterized in that the composite jig includes a floor slab side member extending parallel to the main girder and fixed to the upper surface of the main girder abutting member, and the post-construction anchor is installed on the floor slab side member.

[0012] The composite structure of the main girder and the concrete floor slab of the present invention is characterized in that the gap generated by cutting the joint is filled with a filler.

[0013] The composite structure of the main girder and the concrete floor slab of the present invention is characterized in that the main girder abutting member is made of a flat steel plate or a steel plate with a reinforcing stiffener attached.

[0014] The composite structure of the main girder and the concrete floor slab of the present invention is characterized in that the main girder abutting member is composed of a plurality of strip-shaped steel plates arranged in parallel in the axial direction of the main girder.

[0015] The method for recombining the main girder and the concrete floor slab of the present invention is a method for recombining the concrete floor slab of a bridge separated from the main girder by cutting the joint using the composite structure of the main girder and the concrete floor slab of the present invention to the main girder, comprising: a step of providing post-construction anchors on the lower surface of the concrete floor slab; a step of providing fastening members on the lower surface of the upper flange of the main girder; and a step of integrating the main girder and the concrete floor slab by coupling the post-construction anchors and the fastening members with the composite jig on each side sandwiching the main girder.

[0016] The method for recombining the main girder and the concrete floor slab of the present invention is characterized by including a step of filling the gap generated by cutting the joint with a filler.

[0017] According to the composite structure of the main girder and the concrete floor slab of the present invention and the method for recombining the main girder and the concrete floor slab, by coupling a composite jig with a simple structure such as a main girder abutting member or a combination of a main girder abutting member and a floor slab side member to the fastening member and the post-construction anchor, it is possible to reinforce the shortage of the shear force in the bridge axis direction borne by the stud dibels, concrete, etc. provided on the upper surface of the main girder, which occurs by cutting the joint.

[0018] Also, the post-construction anchors provided on the lower surface of the concrete floor slab are arranged at a predetermined distance from the joint between the main girder and the concrete floor slab. Thereby, the forming work of the cutting surface and the additional plastering work of mortar, which were carried out as pre-treatment when the post-construction anchors were provided on the cutting surface of the joint, can be omitted. In addition, since a working area can be secured, it is possible to improve the working efficiency.

[0019] Furthermore, the main girder abutting member constituting the composite jig may employ a flat steel plate or a steel plate with a reinforcing stiffener attached, or a plurality of strip steel plates may be combined. When configured to combine a plurality of strip steel plates, it is easy for workers to move around in a narrow construction site, and the burden during installation work can be reduced. In addition, the composite jig removed to remove the existing concrete floor slab after recombining can be reused by appropriately adjusting the installation positions of the fastening materials and post-construction anchors in other work areas or sites where floor slab replacement work is carried out.

Advantages of the Invention

[0020] According to the present invention, by arranging the post-construction anchor provided on the lower surface of the concrete floor slab at a predetermined distance from the joint between the main girder and the concrete floor slab, the preparatory work for providing a composite structure can be reduced, so that the cut and separated concrete floor slab and the main girder can be efficiently recombined.

Brief Description of the Drawings

[0021]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0022] As shown in FIGS. 1(a) and 1(b), the bridge 200 has a steel main girder 201 made of H-shaped steel, a concrete floor slab 202 installed on the main girder 201, and a plurality of pairs of inclined members 203 arranged at intervals in the bridge axis direction between the main girders 201 adjacent to each other in the direction perpendicular to the bridge axis. Further, a haunch portion 204 serving as a joint portion with the main girder 201 is formed on the lower surface of the concrete floor slab 202.

[0023] In the bridge 200 having a composite structure in which the above-mentioned concrete floor slab 202 and the steel main girder 201 are integrated, as a rough procedure for carrying out the floor slab replacement work, first, as shown in FIGS. 1(a) and 1(b), the haunch portion 204 forming the joint portion between the concrete floor slab 202 and the main girder 201 is horizontally cut along the upper surface of the main girder 201 so as to form a cutting plane 204a substantially parallel to the bridge axis.

[0024] Next, as shown in FIG. 1(c), the concrete floor slab 202 cut and separated from the main girder 201 is cut substantially vertically along the bridge axis direction and the direction perpendicular to the bridge axis so as to have a size that can be loaded on a transport vehicle, thereby forming a plurality of floor slab pieces 205. After removing the floor slab pieces 205 thus formed by appropriate means, necessary ground treatment is performed on the upper surface of the main girder 201 after removal, and then a new concrete floor slab is installed.

[0025] In the present embodiment, while advancing the cutting operation of the haunch portion 204, as shown in FIG. 2, a plurality of composite structures 100 are formed at intervals in the bridge axis direction between the cut and separated concrete floor slab 202 and the steel main girder 201. Thus, the concrete floor slab 202 and the main girder 201 are integrated to achieve recombining of both. As a result, it is possible to provide a traffic liberation time zone in which ordinary vehicles can be used without restricting the running load or regulating the running lane on the bridge 200 in which the concrete floor slab 202 and the main girder 201 are recombined from the cutting operation of the haunch portion 204 until the operation of forming a plurality of floor slab pieces 205 to remove the concrete floor slab 202 is started.

[0026] A method for recombining the cut and separated concrete floor slab 202 and the main girder 201 will be described below. Prior to this, the details of the composite structure 100 formed by the recombination method will be described.

[0027] ≪≪Composite Structure of Main Girder and Concrete Floor Slab≫≫ As shown in Fig. 3(a), the composite structure 100 includes a post-construction anchor 2 provided on the lower surface of the concrete floor slab 202, a fastening member 3 provided on the main girder 201, a space-holding member 7 interposed in the gap formed in the haunch portion 204 by cutting, a filling material 5 filled in this gap, and a composite jig 1. In some cases, the filling material 5 can be omitted.

[0028] ≪≪Post-construction Anchor and Fastening Member≫≫ The post-construction anchor 2 is provided in a hanging manner at a position on the lower surface of the concrete floor slab 202 at a predetermined distance from the haunch portion 204. As its type, a metal anchor or an adhesive anchor may be adopted. In Fig. 3(a) viewed from the bridge axis direction and Fig. 3(b) viewed from the direction perpendicular to the bridge axis, an example is shown where a total of 16 post-construction anchors 2, consisting of 2 arranged at intervals in the direction perpendicular to the bridge axis and 8 arranged at intervals in the bridge axis direction, are provided in a set on both sides sandwiching the haunch portion 204 of the main girder 201.

[0029] The fastening member 3 is provided in a hanging manner on the lower surface of the upper flange 201a of the main girder 201 using a fixing means such as welding. The fastening member 3 may adopt any type as long as it has a male screw portion that can be screwed with a nut (including a washer) 6, such as a stud bolt. In Figs. 3(a) and 3(b), an example is shown where the fastening members 3 are provided in a set of 6 arranged at intervals in the bridge axis direction on both sides sandwiching the web 201b of the main girder 201. However, the number thereof is not limited to this, and the number required to obtain the desired horizontal shear resistance may be provided.

[0030] ≪Composite Jig≫ As shown in Fig. 3(a), the post-construction jig 1 is arranged on both sides with the web 201b of the main girder 201 in between, and includes a floor slab side member 11, a main girder contact member 12, and an unevenness adjustment member 13. It is a member that combines the post-construction anchor 2 and the fastening material 3 to integrate the cut and separated concrete floor slab 202 and the main girder 201.

[0031] As shown in the exploded view of Fig. 4(a) and the plan view of Fig. 4(b), the floor slab side member 11 is a member arranged parallel to the main girder 201 on the lower side of the post-construction anchor 2, and is made of a long-shaped steel section. In Fig. 4(a), the case of adopting an H-shaped steel is cited as an example, but other steel sections may also be adopted. Further, a through-hole 111 through which the post-construction anchor 2 penetrates is provided on the upper flange of the floor slab side member 11.

[0032] The main girder contact member 12 is a plate-shaped member having a size such that the floor slab side member 11 is fixed to the upper surface of one end side by fixing means such as welding or fastening means such as bolts, and the upper surface of the other end side abuts against the lower surface of the upper flange 201a. In Fig. 4(b), the case of adopting a flat steel plate is cited as an example. Further, a through-hole 121 through which the fastening material 3 penetrates is provided in a region where the main girder contact member 12 abuts against the lower surface of the upper flange 201a.

[0033] In addition, as the main girder contact member 12, a steel plate with a reinforcing stiffener attached may be used in addition to the flat steel plate. The reinforcing stiffener may be installed on the upper surface or the lower surface of the steel plate, or may be attached to both the upper and lower surfaces. The installation method may be welding or bolting. The installation direction is preferably the same as the direction in which the shear force acts, but other directions are also possible. Generally, a flat plate is used as the shape of the stiffener, but an angle material or a CT steel may also be used. By using this stiffener, the thickness of the steel plate can be reduced.

[0034] The unevenness adjustment member 13 is a member inserted when a space is generated between the floor slab side member 11 and the lower surface of the concrete floor slab 202, and any material can be adopted as long as it does not deform significantly by the application of an external force. Further, a through-hole 131 through which the post-construction anchor 2 penetrates is also provided in the unevenness adjustment member 13.

[0035] The composite jig 1 with such a configuration is coupled to the fastening member 3 in a state where the other end side of the main girder contact member 12 is in contact with the lower surface of the upper flange 201a along the web 201b of the main girder 201 with the upper surface in contact therewith. Also, one end side of the main girder contact member 12 has a post-construction anchor 2 coupled to the floor slab side member 11 fixed to the upper surface thereof.

[0036] ≪Space retainer and filling material≫ As shown in Fig. 3(a), the space retaining material 7 is a member driven into the gap formed in the haunch portion 204 by cutting, and any material may be adopted as long as it does not deform under the load of the concrete floor slab 202. For example, wedge-shaped or rectangular block materials can be cited as examples. The arrangement position of the space retaining material 7 may be arranged on both sides sandwiching the web 201b of the main girder 201 when viewed from the bridge axis direction according to the shape and width of the gap, or may be arranged only on one side.

[0037] As shown in Fig. 3(a), the filling material 5 is filled in the gap of the haunch portion 204 whose height direction interval is maintained by the space retaining material 7. In the present embodiment, non-shrink mortar is adopted as the filling material 5, but it is not limited thereto. Considering that a compressive force acts through the concrete floor slab 202 and that it is easy to peel off when the concrete floor slab 202 is removed after recomposition, a material that is strong against compression and weak against tension and has a small shrinkage amount due to drying is suitable. Any material that satisfies these conditions may be adopted as the filling material 5. Also, if the space retaining material 7 can bear the compressive force, the filling material 5 can be omitted in some cases.

[0038] In addition, a sealing material 4 as shown in Fig. 5(c) is disposed in the gap formed in the haunch portion 204 by cutting, together with the space holding material 7. The sealing material 4 is used when filling the gap in the haunch portion 204 with the above-mentioned filling material 5. Its arrangement position is the outer edge of the gap in the haunch portion 204, and any material may be adopted as long as it can block the space filled with the filling material 5. Also, the sealing material 4 may be removed after filling the filling material 5 or may be left in place.

[0039] In the composite structure 100 having the above configuration, the composite jigs 1 are arranged on both sides with the web 201b of the main girder 201 interposed therebetween, and each is coupled to the post-construction anchor 2 and the fastening material 3. Then, the gap generated in the haunch portion 204 is filled with the filling material 5. As a result, as shown in Fig. 3(a), even when there is a shortage due to cutting the haunch portion 204 in the shear force in the bridge axis direction generated when a vehicle passes on the road formed on the concrete floor slab 202, which was borne by the stud dibel 201c, mortar, etc. provided on the upper surface of the main girder 201, this shortage can be reinforced by the composite structure 100.

[0040] Also, even when a compressive force or a vertical force in the bridge axis direction generated when a vehicle passes on the road on the concrete floor slab 202 acts on the cut haunch portion 204, the space holding material 7 and the filling material 5 can maintain the road surface height at the height before cutting the haunch portion 204. And since these external forces are dispersed and act on the entire main girder 201 through the filling material 5, the concrete floor slab 202 is stably supported.

[0041] In this way, even when the haunch portion 204 is cut into an upper half and a lower half by cutting and the main girder 201 and the concrete floor slab 202 are in a state of being cut and separated, the composite structure 100 has the function of integrating them. Therefore, as shown in Fig. 2, by forming a plurality of composite structures 100 at predetermined intervals in the bridge axis direction in the range where the haunch portion 204 is cut, the cut and separated concrete floor slab 202 can be recombined with the main girder 201, and the bridge 200 can function as a composite girder bridge.

[0042] Therefore, even during the period from the operation of cutting the haunch portion 204 and separating the concrete floor slab 202 from the main girder 201 as described with reference to FIG. 1 to the start of the operation of forming a plurality of floor slab pieces 205 to remove the concrete floor slab 202, general vehicles can be used on the road of the recombined bridge 200 without restricting the running load or regulating the driving lane.

[0043] <<Method for recombining the main girder and the concrete floor slab>> Next, a method for recombining the main girder 201 and the concrete floor slab 202 to recombine the cut and separated concrete floor slab 202 to the main girder 201 in a desired section will be described below.

[0044] <<Step of installing the fastening material and step of cutting the haunch portion>> First, as shown in FIG. 5(a), the fastening material 3 is welded and fixed to the lower surface of the upper flange 201a of the main girder 201. The fastening material 3 is welded and fixed at each of the planned positions for forming the synthetic structure 100. Before or after this welding operation, the haunch portion 204 is cut in the bridge axis direction along the upper surface of the main girder 201 to separate the main girder 201 and the concrete floor slab 202.

[0045] The cutting operation is temporarily interrupted when it exceeds an arbitrarily set distance (for example, about 2 m). Since the stud dibel 201c provided on the upper surface of the main girder 201 is embedded in the concrete in the haunch portion 204, this stud dibel 201c is also cut at the same time.

[0046] For the cutting of the haunch portion 204, any cutting tool that can cut the concrete and the stud dibel 201c constituting the haunch portion 204 may be adopted. In this embodiment, a wire saw (not shown) is used to sequentially cut in the bridge axis direction.

[0047] <<Step of driving the space holding material and step of installing the post-construction anchor>> Next, as shown in FIG. 5(b), a pair of space retainers 7 are driven into the gap generated in the haunch portion 204 by cutting. At this time, as shown in FIG. 5(a), if the cut piece 206 of the haunch portion 204 protruding from the upper flange 201a of the main girder 201 remains, it may be removed.

[0048] Also, after-construction anchors 2 are placed on the lower surface of the concrete floor slab 202 provided at a predetermined interval from the haunch portion 204. Note that the placement operation of the after-construction anchors 2 may be performed before the cutting operation as long as it does not affect the cutting operation.

[0049] <Step of connecting the concrete floor slab and the main girder with a composite jig> After that, as shown in FIG. 5(c), the composite jig 1 is installed using the after-construction anchors 2, the fastening members 3, and the nuts (including washers) 6, and the cut and separated concrete floor slab 202 and the main girder 201 are connected.

[0050] The composite jig 1 may be assembled in advance with the floor slab side member 11, the main girder contact member 12, and the uneven adjustment member 13 and carried into the site, or may be assembled on-site and connected to the after-construction anchors 2 and the fastening members 3. Also, in the fastening structure using the fastening members 3 and the nuts (including washers) 6, if frictional joining is used, it will not be single-effective and there will be no displacement.

[0051] The above operations are performed on each side sandwiching the web 201b of the main girder 201, and the composite structure 100 is provided on both sides sandwiching the main girder 201. Also, in the bridge axis direction, a plurality of composite structures 100 are provided at arbitrary separation distances (for example, 30 to 50 cm).

[0052] <Step of filling the gap generated in the haunch portion with a filler> Simultaneously with, or before or after, the operation of installing the synthesis jig 1, as shown in Fig. 5(c), a sealing material 4 is attached to the outer part of the gap of the hunch part 204 in which the space holding material 7 is driven, and this gap is surrounded. After that, the filling material 5 is filled into the gap of the hunch part 204. The process of filling the filling material 5 may be at any time after the space holding material 7 is arranged.

[0053] The operation of cutting the above-mentioned hunch part 204 and the operation of providing the synthesis structure 100 within the cut range are repeatedly carried out. In this way, a plurality of synthesis structures 100 are installed in a desired section with intervals in the bridge axis direction.

[0054] According to the method of re-synthesizing the above-mentioned synthesis structure 100, the main girder 201 and the concrete floor slab 202, the post-construction anchor 2 provided on the lower surface of the concrete floor slab 202 is arranged at a predetermined distance from the hunch part 204. Thereby, the forming work of the cut surface 204a and the additional plastering work of mortar, which were carried out when the post-construction anchor 2 was provided on the cut surface 204a of the hunch part 204 as in the conventional case, can be omitted. Also, since a work area can be secured, it is possible to improve the work efficiency.

[0055] Also, when starting the work related to the removal of the concrete floor slab 202, the nut (including the washer) 6 is removed, and the re-synthesized concrete floor slab 202 can be easily and quickly separated from the main girder 201 only by removing the synthesis jig 1. Furthermore, the removed synthesis jig 1 can be reused by appropriately adjusting the installation position of the post-construction anchor 2 provided on the concrete floor slab 202 and the installation position of the fastening material 3 provided on the lower surface of the upper flange 201a of the main girder 201 in other work areas or sites where the floor slab replacement work is carried out.

[0056] The synthesis structure 100 of the main girder 201 and the concrete floor slab 202 of the present invention, and the method of re-synthesizing the main girder 201 and the concrete floor slab 202 are not limited to the above embodiment, and various changes can be made without departing from the spirit of the present invention.

[0057] For example, in this embodiment, the composite jig 1 employs the floor slab side member 11, the main girder contact member 12, and the unevenness adjustment member 13. However, when the concrete floor slab 202 and the floor slab side member 11 are in good contact with each other on the surface, the unevenness adjustment member 13 can be omitted. Also, when the height of the haunch part 204 is low, the floor slab side member 11 may be omitted. In this case, a through hole through which the post-construction anchor 2 can pass is provided in the main girder contact member 12.

[0058] Also, in this embodiment, the post-construction anchor 2 is continuously provided on one end side along the bridge axis direction of the composite jig 1, but it is not limited to this. For example, as shown in Fig. 6(a), a structure may be adopted in which the post-construction anchor 2 is provided only at the corner of the composite jig 1.

[0059] As shown in Fig. 6(b), the main girder contact member 12 constituting the composite jig 1 may be configured by providing a plurality of strip-shaped steel plates. At this time, the strip-shaped steel plates may be arranged so as to be in contact with each other, or may be arranged with an interval therebetween. In this way, when configured by combining a plurality of strip-shaped steel plates, it is easy for workers to move around at a narrow construction site, and the burden during the installation work can be reduced.

[0060] Furthermore, the composite structure 100 is arranged on both sides of the web 201b of the main girder 201 when viewed from the direction perpendicular to the bridge axis, but it may be provided at positions facing each other. For example, the installation positions may be appropriately set according to the structural conditions of the bridge 200, the construction situation, etc., such as shifting the positions so as to be staggeredly arranged in plan view.

[0061] And the recomposition method of the main girder 201 and the concrete floor slab 202 in this embodiment is applicable to both the method of replacing the entire cross-section (the entire cross-sectional area) of the concrete floor slab 202 and the semi-cross-section floor slab replacement method of replacing the semi-cross-section.

[0062] The half-section floor slab replacement method is, for example, a method in which traffic lane regulation is carried out on a two-lane-up bridge 200, and one of the half-sections on the driving lane side and the passing lane side of the concrete floor slab 202 is replaced with a newly constructed concrete floor slab, and subsequently, the other half-section is also replaced with a newly constructed concrete floor slab in the same manner.

Description of Signs

[0063] 100 Composite structure 1 Composite jig 11 Floor slab side member 111 Through hole 12 Main girder abutting member 121 Through hole 13 Uneven adjustment member 131 Through hole 2 Post-construction anchor 3 Fastening material 4 Sealing material 5 Filling material 6 Nut (including washer) 7 Space retaining material 200 Bridge 201 Main girder 201a Upper flange 201b Web 201c Stud gable 202 Concrete floor slab 203 Inclined structure 204 Hunch part (joint part) 204a Cutting surface 205 Floor slab piece 206 Cut piece

Claims

1. A composite structure of a main girder and a concrete floor slab, which recombines the concrete floor slab of a bridge separated from the main girder by cutting a joint portion back to the main girder, comprising: Construction anchors disposed vertically downward with a predetermined distance from the joint portion on each side of the main girder across the main girder on the lower surface of the concrete floor slab; Fastening members disposed vertically downward on each side of the upper flange lower surface of the main girder across the web; Composite fixtures respectively disposed on both sides of the main girder, connecting the fastening members and the construction anchors; The composite structure of the main girder and the concrete floor slab, characterized in that the composite fixture includes a main girder abutting member on the upper surface, with one end side connected to the construction anchor and the other end side connected to the fastening member.

2. The composite structure of the main girder and the concrete floor slab according to Claim 1, comprising: The composite fixture includes a floor slab side member extending parallel to the main girder and fixed to the upper surface of the main girder abutting member; The composite structure of the main girder and the concrete floor slab, characterized in that the construction anchor is installed on the floor slab side member.

3. In the composite structure of the main girder and the concrete floor slab according to Claim 1, The composite structure of the main girder and the concrete floor slab, characterized in that a filler is filled in the gap generated by cutting the joint portion.

4. In the composite structure of the main girder and the concrete floor slab according to Claim 1, The composite structure of the main girder and the concrete floor slab, characterized in that the main girder abutting member is made of a flat steel plate or a steel plate with a reinforcing stiffener attached.

5. In the composite structure of the main girder and the concrete floor slab according to Claim 1, The composite structure of the main girder and the concrete floor slab, characterized in that the main girder abutting member is composed of a plurality of strip-shaped steel plates arranged in parallel in the axial direction of the main girder.

6. Using the composite structure of the main girder and the concrete floor slab according to any one of Claims 1 to 5, a method for recombining the concrete floor slab of a bridge separated from the main girder by cutting the joint and recombining it with the main girder, comprising: a step of providing post-construction anchors on the lower surface of the concrete floor slab; a step of providing fastening materials on the lower surface of the upper flange of the main girder; a step of integrating the main girder and the concrete floor slab by connecting the post-construction anchors and the fastening materials with the composite jig on each side sandwiching the main girder; A method for recombining a main girder and a concrete floor slab, characterized by comprising the above steps.

7. In the method for recombining a main girder and a concrete floor slab according to Claim 6, A method for recombining a main girder and a concrete floor slab, characterized by including a step of filling the gap generated by cutting the joint with a filling material.

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